NAME | TABLE SUMMARY | Open_vSwitch TABLE | Bridge TABLE | Port TABLE | Interface TABLE | Flow_Table TABLE | QoS TABLE | Queue TABLE | Mirror TABLE | Controller TABLE | Manager TABLE | NetFlow TABLE | SSL TABLE | sFlow TABLE | IPFIX TABLE | Flow_Sample_Collector_Set TABLE | AutoAttach TABLE | COLOPHON

ovs-vswitchd.conf.db(5)      Open vSwitch Manual     ovs-vswitchd.conf.db(5)

NAME         top

       ovs-vswitchd.conf.db - Open_vSwitch database schema

       A  database  with  this  schema  holds the configuration for one Open
       vSwitch daemon. The top-level configuration for  the  daemon  is  the
       Open_vSwitch  table,  which  must have exactly one record. Records in
       other tables are significant only when they can be  reached  directly
       or  indirectly  from  the  Open_vSwitch  table.  Records that are not
       reachable from the Open_vSwitch table are automatically deleted  from
       the  database, except for records in a few distinguished ``root set’’
       tables.

   Common Columns
       Most tables contain  two  special  columns,  named  other_config  and
       external_ids. These columns have the same form and purpose each place
       that they appear, so we describe them here to save space later.

              other_config: map of string-string pairs
                     Key-value pairs for configuring rarely  used  features.
                     Supported  keys,  along  with  the forms taken by their
                     values, are documented individually for each table.

                     A few tables do not have other_config  columns  because
                     no key-value pairs have yet been defined for them.

              external_ids: map of string-string pairs
                     Key-value  pairs  for  use  by external frameworks that
                     integrate  with  Open  vSwitch,  rather  than  by  Open
                     vSwitch  itself.  System  integrators should either use
                     the Open vSwitch development mailing list to coordinate
                     on  common  key-value  definitions, or choose key names
                     that are likely to be unique. In some cases, where key-
                     value  pairs  have  been  defined that are likely to be
                     widely useful, they  are  documented  individually  for
                     each table.

TABLE SUMMARY         top

       The following list summarizes the purpose of each of the tables in
       the Open_vSwitch database.  Each table is described in more detail on
       a later page.

       Table     Purpose
       Open_vSwitch
                 Open vSwitch configuration.
       Bridge    Bridge configuration.
       Port      Port configuration.
       Interface One physical network device in a Port.
       Flow_Table
                 OpenFlow table configuration
       QoS       Quality of Service configuration
       Queue     QoS output queue.
       Mirror    Port mirroring.
       Controller
                 OpenFlow controller configuration.
       Manager   OVSDB management connection.
       NetFlow   NetFlow configuration.
       SSL       SSL configuration.
       sFlow     sFlow configuration.
       IPFIX     IPFIX configuration.
       Flow_Sample_Collector_Set
                 Flow_Sample_Collector_Set configuration.
       AutoAttach
                 AutoAttach configuration.

Open_vSwitch TABLE         top

       Configuration for an Open vSwitch daemon. There must be exactly one
       record in the Open_vSwitch table.

   Summary:
       Configuration:
         bridges                     set of Bridges
         ssl                         optional SSL
         external_ids : system-id    optional string
         external_ids : xs-system-uuid
                                     optional string
         external_ids : hostname     optional string
         external_ids : rundir       optional string
         other_config : stats-update-interval
                                     optional string, containing an integer,
                                     at least 5,000
         other_config : flow-restore-wait
                                     optional string, either true or false
         other_config : flow-limit   optional string, containing an integer,
                                     at least 0
         other_config : max-idle     optional string, containing an integer,
                                     at least 500
         other_config : hw-offload   optional string, either true or false
         other_config : tc-policy    optional string
         other_config : dpdk-init    optional string, either true or false
         other_config : dpdk-lcore-mask
                                     optional string, containing an integer,
                                     at least 1
         other_config : pmd-cpu-mask
                                     optional string
         other_config : dpdk-alloc-mem
                                     optional string, containing an integer,
                                     at least 0
         other_config : dpdk-socket-mem
                                     optional string
         other_config : dpdk-hugepage-dir
                                     optional string
         other_config : dpdk-extra   optional string
         other_config : vhost-sock-dir
                                     optional string
         other_config : n-handler-threads
                                     optional string, containing an integer,
                                     at least 1
         other_config : n-revalidator-threads
                                     optional string, containing an integer,
                                     at least 1
         other_config : emc-insert-inv-prob
                                     optional string, containing an integer,
                                     in range 0 to 4,294,967,295
         other_config : vlan-limit   optional string, containing an integer,
                                     at least 0
       Status:
         next_cfg                    integer
         cur_cfg                     integer
         Statistics:
            other_config : enable-statistics
                                     optional string, either true or false
            statistics : cpu         optional string, containing an integer,
                                     at least 1
            statistics : load_average
                                     optional string
            statistics : memory      optional string
            statistics : process_NAME
                                     optional string
            statistics : file_systems
                                     optional string
       Version Reporting:
         ovs_version                 optional string
         db_version                  optional string
         system_type                 optional string
         system_version              optional string
       Capabilities:
         datapath_types              set of strings
         iface_types                 set of strings
       Database Configuration:
         manager_options             set of Managers
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
     Configuration:

       bridges: set of Bridges
              Set of bridges managed by the daemon.

       ssl: optional SSL
              SSL used globally by the daemon.

       external_ids : system-id: optional string
              A unique identifier for the Open vSwitch’s physical host. The
              form of the identifier depends on the type of the host. On a
              Citrix XenServer, this will likely be the same as
              external_ids:xs-system-uuid.

       external_ids : xs-system-uuid: optional string
              The Citrix XenServer universally unique identifier for the
              physical host as displayed by xe host-list.

       external_ids : hostname: optional string
              The hostname for the host running Open vSwitch. This is a
              fully qualified domain name since version 2.6.2.

       external_ids : rundir: optional string
              In Open vSwitch 2.8 and later, the run directory of the
              running Open vSwitch daemon. This directory is used for
              runtime state such as control and management sockets. The
              value of other_config:vhost-sock-dir is relative to this
              directory.

       other_config : stats-update-interval: optional string, containing an
       integer, at least 5,000
              Interval for updating statistics to the database, in
              milliseconds. This option will affect the update of the
              statistics column in the following tables: Port, Interface ,
              Mirror.

              Default value is 5000 ms.

              Getting statistics more frequently can be achieved via
              OpenFlow.

       other_config : flow-restore-wait: optional string, either true or
       false
              When ovs-vswitchd starts up, it has an empty flow table and
              therefore it handles all arriving packets in its default
              fashion according to its configuration, by dropping them or
              sending them to an OpenFlow controller or switching them as a
              standalone switch. This behavior is ordinarily desirable.
              However, if ovs-vswitchd is restarting as part of a ``hot-
              upgrade,’’ then this leads to a relatively long period during
              which packets are mishandled.

              This option allows for improvement. When ovs-vswitchd starts
              with this value set as true, it will neither flush or expire
              previously set datapath flows nor will it send and receive any
              packets to or from the datapath. When this value is later set
              to false, ovs-vswitchd will start receiving packets from the
              datapath and re-setup the flows.

              Thus, with this option, the procedure for a hot-upgrade of
              ovs-vswitchd becomes roughly the following:

              1.
                Stop ovs-vswitchd.

              2.
                Set other_config:flow-restore-wait to true.

              3.
                Start ovs-vswitchd.

              4.
                Use ovs-ofctl (or some other program, such as an OpenFlow
                controller) to restore the OpenFlow flow table to the
                desired state.

              5.
                Set other_config:flow-restore-wait to false (or remove it
                entirely from the database).

              The ovs-ctl’s ``restart’’ and ``force-reload-kmod’’ functions
              use the above config option during hot upgrades.

       other_config : flow-limit: optional string, containing an integer, at
       least 0
              The maximum number of flows allowed in the datapath flow
              table. Internally OVS will choose a flow limit which will
              likely be lower than this number, based on real time network
              conditions. Tweaking this value is discouraged unless you know
              exactly what you’re doing.

              The default is 200000.

       other_config : max-idle: optional string, containing an integer, at
       least 500
              The maximum time (in ms) that idle flows will remain cached in
              the datapath. Internally OVS will check the validity and
              activity for datapath flows regularly and may expire flows
              quicker than this number, based on real time network
              conditions. Tweaking this value is discouraged unless you know
              exactly what you’re doing.

              The default is 10000.

       other_config : hw-offload: optional string, either true or false
              Set this value to true to enable netdev flow offload.

              The default value is false. Changing this value requires
              restarting the daemon

              Currently Open vSwitch supports hardware offloading on Linux
              systems. On other systems, this value is ignored. This
              functionality is considered ’experimental’. Depending on which
              OpenFlow matches and actions are configured, which kernel
              version is used, and what hardware is available, Open vSwitch
              may not be able to offload functionality to hardware.

       other_config : tc-policy: optional string
              Specified the policy used with HW offloading. Options: none -
              Add software rule and offload rule to HW. skip_sw - Offload
              rule to HW only. skip_hw - Add software rule without
              offloading rule to HW.

              This is only relevant if HW offloading is enabled (hw-
              offload).

              The default value is none.

       other_config : dpdk-init: optional string, either true or false
              Set this value to true to enable runtime support for DPDK
              ports. The vswitch must have compile-time support for DPDK as
              well.

              The default value is false. Changing this value requires
              restarting the daemon

              If this value is false at startup, any dpdk ports which are
              configured in the bridge will fail due to memory errors.

       other_config : dpdk-lcore-mask: optional string, containing an
       integer, at least 1
              Specifies the CPU cores where dpdk lcore threads should be
              spawned. The DPDK lcore threads are used for DPDK library
              tasks, such as library internal message processing, logging,
              etc. Value should be in the form of a hex string (so ’0x123’)
              similar to the ’taskset’ mask input.

              The lowest order bit corresponds to the first CPU core. A set
              bit means the corresponding core is available and an lcore
              thread will be created and pinned to it. If the input does not
              cover all cores, those uncovered cores are considered not set.

              For performance reasons, it is best to set this to a single
              core on the system, rather than allow lcore threads to float.

              If not specified, the value will be determined by choosing the
              lowest CPU core from initial cpu affinity list. Otherwise, the
              value will be passed directly to the DPDK library.

       other_config : pmd-cpu-mask: optional string
              Specifies CPU mask for setting the cpu affinity of PMD (Poll
              Mode Driver) threads. Value should be in the form of hex
              string, similar to the dpdk EAL ’-c COREMASK’ option input or
              the ’taskset’ mask input.

              The lowest order bit corresponds to the first CPU core. A set
              bit means the corresponding core is available and a pmd thread
              will be created and pinned to it. If the input does not cover
              all cores, those uncovered cores are considered not set.

              If not specified, one pmd thread will be created for each numa
              node and pinned to any available core on the numa node by
              default.

       other_config : dpdk-alloc-mem: optional string, containing an
       integer, at least 0
              Specifies the amount of memory to preallocate from the
              hugepage pool, regardless of socket. It is recommended that
              dpdk-socket-mem is used instead.

       other_config : dpdk-socket-mem: optional string
              Specifies the amount of memory to preallocate from the
              hugepage pool, on a per-socket basis.

              The specifier is a comma-separated string, in ascending order
              of CPU socket. E.g. On a four socket system 1024,0,2048 would
              set socket 0 to preallocate 1024MB, socket 1 to preallocate
              0MB, socket 2 to preallocate 2048MB and socket 3 (no value
              given) to preallocate 0MB.

              If dpdk-socket-mem and dpdk-alloc-mem are not specified, dpdk-
              socket-mem will be used and the default value is 1024,0. If
              dpdk-socket-mem and dpdk-alloc-mem are specified at same time,
              dpdk-socket-mem will be used as default. Changing this value
              requires restarting the daemon.

       other_config : dpdk-hugepage-dir: optional string
              Specifies the path to the hugetlbfs mount point.

              If not specified, this will be guessed by the DPDK library
              (default is /dev/hugepages). Changing this value requires
              restarting the daemon.

       other_config : dpdk-extra: optional string
              Specifies additional eal command line arguments for DPDK.

              The default is empty. Changing this value requires restarting
              the daemon

       other_config : vhost-sock-dir: optional string
              Specifies a relative path from external_ids:rundir to the
              vhost-user unix domain socket files. If this value is unset,
              the sockets are put directly in external_ids:rundir.

              Changing this value requires restarting the daemon.

       other_config : n-handler-threads: optional string, containing an
       integer, at least 1
              Specifies the number of threads for software datapaths to use
              for handling new flows. The default the number of online CPU
              cores minus the number of revalidators.

              This configuration is per datapath. If you have more than one
              software datapath (e.g. some system bridges and some netdev
              bridges), then the total number of threads is
              n-handler-threads times the number of software datapaths.

       other_config : n-revalidator-threads: optional string, containing an
       integer, at least 1
              Specifies the number of threads for software datapaths to use
              for revalidating flows in the datapath. Typically, there is a
              direct correlation between the number of revalidator threads,
              and the number of flows allowed in the datapath. The default
              is the number of cpu cores divided by four plus one. If
              n-handler-threads is set, the default changes to the number of
              cpu cores minus the number of handler threads.

              This configuration is per datapath. If you have more than one
              software datapath (e.g. some system bridges and some netdev
              bridges), then the total number of threads is
              n-handler-threads times the number of software datapaths.

       other_config : emc-insert-inv-prob: optional string, containing an
       integer, in range 0 to 4,294,967,295
              Specifies the inverse probability (1/emc-insert-inv-prob) of a
              flow being inserted into the Exact Match Cache (EMC). On
              average one in every emc-insert-inv-prob packets that generate
              a unique flow will cause an insertion into the EMC. A value of
              1 will result in an insertion for every flow (1/1 = 100%)
              whereas a value of zero will result in no insertions and
              essentially disable the EMC.

              Defaults to 100 ie. there is (1/100 =) 1% chance of EMC
              insertion.

       other_config : vlan-limit: optional string, containing an integer, at
       least 0
              Limits the number of VLAN headers that can be matched to the
              specified number. Further VLAN headers will be treated as
              payload, e.g. a packet with more 802.1q headers will match
              Ethernet type 0x8100.

              Value 0 means unlimited. The actual number of supported VLAN
              headers is the smallest of vlan-limit, the number of VLANs
              supported by Open vSwitch userspace (currently 2), and the
              number supported by the datapath.

              If this value is absent, the default is currently 1. This
              maintains backward compatibility with controllers that were
              designed for use with Open vSwitch versions earlier than 2.8,
              which only supported one VLAN.

     Status:

       next_cfg: integer
              Sequence number for client to increment. When a client
              modifies any part of the database configuration and wishes to
              wait for Open vSwitch to finish applying the changes, it may
              increment this sequence number.

       cur_cfg: integer
              Sequence number that Open vSwitch sets to the current value of
              next_cfg after it finishes applying a set of configuration
              changes.

     Statistics:

       The statistics column contains key-value pairs that report statistics
       about a system running an Open vSwitch. These are updated
       periodically (currently, every 5 seconds). Key-value pairs that
       cannot be determined or that do not apply to a platform are omitted.

       other_config : enable-statistics: optional string, either true or
       false
              Statistics are disabled by default to avoid overhead in the
              common case when statistics gathering is not useful. Set this
              value to true to enable populating the statistics column or to
              false to explicitly disable it.

       statistics : cpu: optional string, containing an integer, at least 1
              Number of CPU processors, threads, or cores currently online
              and available to the operating system on which Open vSwitch is
              running, as an integer. This may be less than the number
              installed, if some are not online or if they are not available
              to the operating system.

              Open vSwitch userspace processes are not multithreaded, but
              the Linux kernel-based datapath is.

       statistics : load_average: optional string
              A comma-separated list of three floating-point numbers,
              representing the system load average over the last 1, 5, and
              15 minutes, respectively.

       statistics : memory: optional string
              A comma-separated list of integers, each of which represents a
              quantity of memory in kilobytes that describes the operating
              system on which Open vSwitch is running. In respective order,
              these values are:

              1.
                Total amount of RAM allocated to the OS.

              2.
                RAM allocated to the OS that is in use.

              3.
                RAM that can be flushed out to disk or otherwise discarded
                if that space is needed for another purpose. This number is
                necessarily less than or equal to the previous value.

              4.
                Total disk space allocated for swap.

              5.
                Swap space currently in use.

              On Linux, all five values can be determined and are included.
              On other operating systems, only the first two values can be
              determined, so the list will only have two values.

       statistics : process_NAME: optional string
              One such key-value pair, with NAME replaced by a process name,
              will exist for each running Open vSwitch daemon process, with
              name replaced by the daemon’s name (e.g.
              process_ovs-vswitchd). The value is a comma-separated list of
              integers. The integers represent the following, with memory
              measured in kilobytes and durations in milliseconds:

              1.
                The process’s virtual memory size.

              2.
                The process’s resident set size.

              3.
                The amount of user and system CPU time consumed by the
                process.

              4.
                The number of times that the process has crashed and been
                automatically restarted by the monitor.

              5.
                The duration since the process was started.

              6.
                The duration for which the process has been running.

              The interpretation of some of these values depends on whether
              the process was started with the --monitor. If it was not,
              then the crash count will always be 0 and the two durations
              will always be the same. If --monitor was given, then the
              crash count may be positive; if it is, the latter duration is
              the amount of time since the most recent crash and restart.

              There will be one key-value pair for each file in Open
              vSwitch’s ``run directory’’ (usually /var/run/openvswitch)
              whose name ends in .pid, whose contents are a process ID, and
              which is locked by a running process. The name is taken from
              the pidfile’s name.

              Currently Open vSwitch is only able to obtain all of the above
              detail on Linux systems. On other systems, the same key-value
              pairs will be present but the values will always be the empty
              string.

       statistics : file_systems: optional string
              A space-separated list of information on local, writable file
              systems. Each item in the list describes one file system and
              consists in turn of a comma-separated list of the following:

              1.
                Mount point, e.g. / or /var/log. Any spaces or commas in the
                mount point are replaced by underscores.

              2.
                Total size, in kilobytes, as an integer.

              3.
                Amount of storage in use, in kilobytes, as an integer.

              This key-value pair is omitted if there are no local, writable
              file systems or if Open vSwitch cannot obtain the needed
              information.

     Version Reporting:

       These columns report the types and versions of the hardware and
       software running Open vSwitch. We recommend in general that software
       should test whether specific features are supported instead of
       relying on version number checks. These values are primarily intended
       for reporting to human administrators.

       ovs_version: optional string
              The Open vSwitch version number, e.g. 1.1.0.

       db_version: optional string
              The database schema version number, e.g. 1.2.3. See ovsdb-
              tool(1) for an explanation of the numbering scheme.

              The schema version is part of the database schema, so it can
              also be retrieved by fetching the schema using the Open
              vSwitch database protocol.

       system_type: optional string
              An identifier for the type of system on top of which Open
              vSwitch runs, e.g. XenServer or KVM.

              System integrators are responsible for choosing and setting an
              appropriate value for this column.

       system_version: optional string
              The version of the system identified by system_type, e.g.
              5.6.100-39265p on XenServer 5.6.100 build 39265.

              System integrators are responsible for choosing and setting an
              appropriate value for this column.

     Capabilities:

       These columns report capabilities of the Open vSwitch instance.

       datapath_types: set of strings
              This column reports the different dpifs registered with the
              system. These are the values that this instance supports in
              the datapath_type column of the Bridge table.

       iface_types: set of strings
              This column reports the different netdevs registered with the
              system. These are the values that this instance supports in
              the type column of the Interface table.

     Database Configuration:

       These columns primarily configure the Open vSwitch database
       (ovsdb-server), not the Open vSwitch switch (ovs-vswitchd). The OVSDB
       database also uses the ssl settings.

       The Open vSwitch switch does read the database configuration to
       determine remote IP addresses to which in-band control should apply.

       manager_options: set of Managers
              Database clients to which the Open vSwitch database server
              should connect or to which it should listen, along with
              options for how these connection should be configured. See the
              Manager table for more information.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Bridge TABLE         top

       Configuration for a bridge within an Open_vSwitch.

       A Bridge record represents an Ethernet switch with one or more
       ``ports,’’ which are the Port records pointed to by the Bridge’s
       ports column.

   Summary:
       Core Features:
         name                        immutable string (must be unique within
                                     table)
         ports                       set of Ports
         mirrors                     set of Mirrors
         netflow                     optional NetFlow
         sflow                       optional sFlow
         ipfix                       optional IPFIX
         flood_vlans                 set of up to 4,096 integers, in range 0
                                     to 4,095
         auto_attach                 optional AutoAttach
       OpenFlow Configuration:
         controller                  set of Controllers
         flow_tables                 map of integer-Flow_Table pairs, key in
                                     range 0 to 254
         fail_mode                   optional string, either secure or
                                     standalone
         datapath_id                 optional string
         datapath_version            string
         other_config : datapath-id  optional string
         other_config : dp-desc      optional string
         other_config : disable-in-band
                                     optional string, either true or false
         other_config : in-band-queue
                                     optional string, containing an integer,
                                     in range 0 to 4,294,967,295
         protocols                   set of strings, one of OpenFlow10,
                                     OpenFlow11, OpenFlow12, OpenFlow13,
                                     OpenFlow14, OpenFlow15, or OpenFlow16
       Spanning Tree Configuration:
         STP Configuration:
            stp_enable               boolean
            other_config : stp-system-id
                                     optional string
            other_config : stp-priority
                                     optional string, containing an integer,
                                     in range 0 to 65,535
            other_config : stp-hello-time
                                     optional string, containing an integer,
                                     in range 1 to 10
            other_config : stp-max-age
                                     optional string, containing an integer,
                                     in range 6 to 40
            other_config : stp-forward-delay
                                     optional string, containing an integer,
                                     in range 4 to 30
            other_config : mcast-snooping-aging-time
                                     optional string, containing an integer,
                                     at least 1
            other_config : mcast-snooping-table-size
                                     optional string, containing an integer,
                                     at least 1
            other_config : mcast-snooping-disable-flood-unregistered
                                     optional string, either true or false
         STP Status:
            status : stp_bridge_id   optional string
            status : stp_designated_root
                                     optional string
            status : stp_root_path_cost
                                     optional string
       Rapid Spanning Tree:
         RSTP Configuration:
            rstp_enable              boolean
            other_config : rstp-address
                                     optional string
            other_config : rstp-priority
                                     optional string, containing an integer,
                                     in range 0 to 61,440
            other_config : rstp-ageing-time
                                     optional string, containing an integer,
                                     in range 10 to 1,000,000
            other_config : rstp-force-protocol-version
                                     optional string, containing an integer
            other_config : rstp-max-age
                                     optional string, containing an integer,
                                     in range 6 to 40
            other_config : rstp-forward-delay
                                     optional string, containing an integer,
                                     in range 4 to 30
            other_config : rstp-transmit-hold-count
                                     optional string, containing an integer,
                                     in range 1 to 10
         RSTP Status:
            rstp_status : rstp_bridge_id
                                     optional string
            rstp_status : rstp_root_id
                                     optional string
            rstp_status : rstp_root_path_cost
                                     optional string, containing an integer,
                                     at least 0
            rstp_status : rstp_designated_id
                                     optional string
            rstp_status : rstp_designated_port_id
                                     optional string
            rstp_status : rstp_bridge_port_id
                                     optional string
       Multicast Snooping Configuration:
         mcast_snooping_enable       boolean
       Other Features:
         datapath_type               string
         external_ids : bridge-id    optional string
         external_ids : xs-network-uuids
                                     optional string
         other_config : hwaddr       optional string
         other_config : forward-bpdu
                                     optional string, either true or false
         other_config : mac-aging-time
                                     optional string, containing an integer,
                                     at least 1
         other_config : mac-table-size
                                     optional string, containing an integer,
                                     at least 1
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
     Core Features:

       name: immutable string (must be unique within table)
              Bridge identifier. Must be unique among the names of ports,
              interfaces, and bridges on a host.

              The name must be alphanumeric and must not contain forward or
              backward slashes. The name of a bridge is also the name of an
              Interface (and a Port) within the bridge, so the restrictions
              on the name column in the Interface table, particularly on
              length, also apply to bridge names. Refer to the documentation
              for Interface names for details.

       ports: set of Ports
              Ports included in the bridge.

       mirrors: set of Mirrors
              Port mirroring configuration.

       netflow: optional NetFlow
              NetFlow configuration.

       sflow: optional sFlow
              sFlow(R) configuration.

       ipfix: optional IPFIX
              IPFIX configuration.

       flood_vlans: set of up to 4,096 integers, in range 0 to 4,095
              VLAN IDs of VLANs on which MAC address learning should be
              disabled, so that packets are flooded instead of being sent to
              specific ports that are believed to contain packets’
              destination MACs. This should ordinarily be used to disable
              MAC learning on VLANs used for mirroring (RSPAN VLANs). It may
              also be useful for debugging.

              SLB bonding (see the bond_mode column in the Port table) is
              incompatible with flood_vlans. Consider using another bonding
              mode or a different type of mirror instead.

       auto_attach: optional AutoAttach
              Auto Attach configuration.

     OpenFlow Configuration:

       controller: set of Controllers
              OpenFlow controller set. If unset, then no OpenFlow
              controllers will be used.

              If there are primary controllers, removing all of them clears
              the flow table. If there are no primary controllers, adding
              one also clears the flow table. Other changes to the set of
              controllers, such as adding or removing a service controller,
              adding another primary controller to supplement an existing
              primary controller, or removing only one of two primary
              controllers, have no effect on the flow table.

       flow_tables: map of integer-Flow_Table pairs, key in range 0 to 254
              Configuration for OpenFlow tables. Each pair maps from an
              OpenFlow table ID to configuration for that table.

       fail_mode: optional string, either secure or standalone
              When a controller is configured, it is, ordinarily,
              responsible for setting up all flows on the switch. Thus, if
              the connection to the controller fails, no new network
              connections can be set up. If the connection to the controller
              stays down long enough, no packets can pass through the switch
              at all. This setting determines the switch’s response to such
              a situation. It may be set to one of the following:

              standalone
                     If no message is received from the controller for three
                     times the inactivity probe interval (see
                     inactivity_probe), then Open vSwitch will take over
                     responsibility for setting up flows. In this mode, Open
                     vSwitch causes the bridge to act like an ordinary MAC-
                     learning switch. Open vSwitch will continue to retry
                     connecting to the controller in the background and,
                     when the connection succeeds, it will discontinue its
                     standalone behavior.

              secure Open vSwitch will not set up flows on its own when the
                     controller connection fails or when no controllers are
                     defined. The bridge will continue to retry connecting
                     to any defined controllers forever.

              The default is standalone if the value is unset, but future
              versions of Open vSwitch may change the default.

              The standalone mode can create forwarding loops on a bridge
              that has more than one uplink port unless STP is enabled. To
              avoid loops on such a bridge, configure secure mode or enable
              STP (see stp_enable).

              When more than one controller is configured, fail_mode is
              considered only when none of the configured controllers can be
              contacted.

              Changing fail_mode when no primary controllers are configured
              clears the flow table.

       datapath_id: optional string
              Reports the OpenFlow datapath ID in use. Exactly 16 hex
              digits. (Setting this column has no useful effect. Set other-
              config:datapath-id instead.)

       datapath_version: string
              Reports the version number of the Open vSwitch datapath in
              use. This allows management software to detect and report
              discrepancies between Open vSwitch userspace and datapath
              versions. (The ovs_version column in the Open_vSwitch reports
              the Open vSwitch userspace version.) The version reported
              depends on the datapath in use:

              ·      When the kernel module included in the Open vSwitch
                     source tree is used, this column reports the Open
                     vSwitch version from which the module was taken.

              ·      When the kernel module that is part of the upstream
                     Linux kernel is used, this column reports <unknown>.

              ·      When the datapath is built into the ovs-vswitchd
                     binary, this column reports <built-in>. A built-in
                     datapath is by definition the same version as the rest
                     of the Open VSwitch userspace.

              ·      Other datapaths (such as the Hyper-V kernel datapath)
                     currently report <unknown>.

              A version discrepancy between ovs-vswitchd and the datapath in
              use is not normally cause for alarm. The Open vSwitch kernel
              datapaths for Linux and Hyper-V, in particular, are designed
              for maximum inter-version compatibility: any userspace version
              works with with any kernel version. Some reasons do exist to
              insist on particular user/kernel pairings. First, newer kernel
              versions add new features, that can only be used by new-enough
              userspace, e.g. VXLAN tunneling requires certain minimal
              userspace and kernel versions. Second, as an extension to the
              first reason, some newer kernel versions add new features for
              enhancing performance that only new-enough userspace versions
              can take advantage of.

       other_config : datapath-id: optional string
              Exactly 16 hex digits to set the OpenFlow datapath ID to a
              specific value. May not be all-zero.

       other_config : dp-desc: optional string
              Human readable description of datapath. It is a maximum 256
              byte-long free-form string to describe the datapath for
              debugging purposes, e.g. switch3 in room 3120.

       other_config : disable-in-band: optional string, either true or false
              If set to true, disable in-band control on the bridge
              regardless of controller and manager settings.

       other_config : in-band-queue: optional string, containing an integer,
       in range 0 to 4,294,967,295
              A queue ID as a nonnegative integer. This sets the OpenFlow
              queue ID that will be used by flows set up by in-band control
              on this bridge. If unset, or if the port used by an in-band
              control flow does not have QoS configured, or if the port does
              not have a queue with the specified ID, the default queue is
              used instead.

       protocols: set of strings, one of OpenFlow10, OpenFlow11, OpenFlow12,
       OpenFlow13, OpenFlow14, OpenFlow15, or OpenFlow16
              List of OpenFlow protocols that may be used when negotiating a
              connection with a controller. OpenFlow 1.0, 1.1, 1.2, 1.3, and
              1.4 are enabled by default if this column is empty.

              OpenFlow 1.5 and 1.6 are not enabled by default because their
              implementations are missing features. In addition, the
              OpenFlow 1.6 specification is still under development and thus
              subject to change.

     Spanning Tree Configuration:

       The IEEE 802.1D Spanning Tree Protocol (STP) is a network protocol
       that ensures loop-free topologies. It allows redundant links to be
       included in the network to provide automatic backup paths if the
       active links fails.

       These settings configure the slower-to-converge but still widely
       supported version of Spanning Tree Protocol, sometimes known as
       802.1D-1998. Open vSwitch also supports the newer Rapid Spanning Tree
       Protocol (RSTP), documented later in the section titled Rapid
       Spanning Tree Configuration.

     STP Configuration:

       stp_enable: boolean
              Enable spanning tree on the bridge. By default, STP is
              disabled on bridges. Bond, internal, and mirror ports are not
              supported and will not participate in the spanning tree.

              STP and RSTP are mutually exclusive. If both are enabled, RSTP
              will be used.

       other_config : stp-system-id: optional string
              The bridge’s STP identifier (the lower 48 bits of the bridge-
              id) in the form xx:xx:xx:xx:xx:xx. By default, the identifier
              is the MAC address of the bridge.

       other_config : stp-priority: optional string, containing an integer,
       in range 0 to 65,535
              The bridge’s relative priority value for determining the root
              bridge (the upper 16 bits of the bridge-id). A bridge with the
              lowest bridge-id is elected the root. By default, the priority
              is 0x8000.

       other_config : stp-hello-time: optional string, containing an
       integer, in range 1 to 10
              The interval between transmissions of hello messages by
              designated ports, in seconds. By default the hello interval is
              2 seconds.

       other_config : stp-max-age: optional string, containing an integer,
       in range 6 to 40
              The maximum age of the information transmitted by the bridge
              when it is the root bridge, in seconds. By default, the
              maximum age is 20 seconds.

       other_config : stp-forward-delay: optional string, containing an
       integer, in range 4 to 30
              The delay to wait between transitioning root and designated
              ports to forwarding, in seconds. By default, the forwarding
              delay is 15 seconds.

       other_config : mcast-snooping-aging-time: optional string, containing
       an integer, at least 1
              The maximum number of seconds to retain a multicast snooping
              entry for which no packets have been seen. The default is
              currently 300 seconds (5 minutes). The value, if specified, is
              forced into a reasonable range, currently 15 to 3600 seconds.

       other_config : mcast-snooping-table-size: optional string, containing
       an integer, at least 1
              The maximum number of multicast snooping addresses to learn.
              The default is currently 2048. The value, if specified, is
              forced into a reasonable range, currently 10 to 1,000,000.

       other_config : mcast-snooping-disable-flood-unregistered: optional
       string, either true or false
              If set to false, unregistered multicast packets are forwarded
              to all ports. If set to true, unregistered multicast packets
              are forwarded to ports connected to multicast routers.

     STP Status:

       These key-value pairs report the status of 802.1D-1998. They are
       present only if STP is enabled (via the stp_enable column).

       status : stp_bridge_id: optional string
              The bridge ID used in spanning tree advertisements, in the
              form xxxx.yyyyyyyyyyyy where the xs are the STP priority, the
              ys are the STP system ID, and each x and y is a hex digit.

       status : stp_designated_root: optional string
              The designated root for this spanning tree, in the same form
              as status:stp_bridge_id. If this bridge is the root, this will
              have the same value as status:stp_bridge_id, otherwise it will
              differ.

       status : stp_root_path_cost: optional string
              The path cost of reaching the designated bridge. A lower
              number is better. The value is 0 if this bridge is the root,
              otherwise it is higher.

     Rapid Spanning Tree:

       Rapid Spanning Tree Protocol (RSTP), like STP, is a network protocol
       that ensures loop-free topologies. RSTP superseded STP with the
       publication of 802.1D-2004. Compared to STP, RSTP converges more
       quickly and recovers more quickly from failures.

     RSTP Configuration:

       rstp_enable: boolean
              Enable Rapid Spanning Tree on the bridge. By default, RSTP is
              disabled on bridges. Bond, internal, and mirror ports are not
              supported and will not participate in the spanning tree.

              STP and RSTP are mutually exclusive. If both are enabled, RSTP
              will be used.

       other_config : rstp-address: optional string
              The bridge’s RSTP address (the lower 48 bits of the bridge-id)
              in the form xx:xx:xx:xx:xx:xx. By default, the address is the
              MAC address of the bridge.

       other_config : rstp-priority: optional string, containing an integer,
       in range 0 to 61,440
              The bridge’s relative priority value for determining the root
              bridge (the upper 16 bits of the bridge-id). A bridge with the
              lowest bridge-id is elected the root. By default, the priority
              is 0x8000 (32768). This value needs to be a multiple of 4096,
              otherwise it’s rounded to the nearest inferior one.

       other_config : rstp-ageing-time: optional string, containing an
       integer, in range 10 to 1,000,000
              The Ageing Time parameter for the Bridge. The default value is
              300 seconds.

       other_config : rstp-force-protocol-version: optional string,
       containing an integer
              The Force Protocol Version parameter for the Bridge. This can
              take the value 0 (STP Compatibility mode) or 2 (the default,
              normal operation).

       other_config : rstp-max-age: optional string, containing an integer,
       in range 6 to 40
              The maximum age of the information transmitted by the Bridge
              when it is the Root Bridge. The default value is 20.

       other_config : rstp-forward-delay: optional string, containing an
       integer, in range 4 to 30
              The delay used by STP Bridges to transition Root and
              Designated Ports to Forwarding. The default value is 15.

       other_config : rstp-transmit-hold-count: optional string, containing
       an integer, in range 1 to 10
              The Transmit Hold Count used by the Port Transmit state
              machine to limit transmission rate. The default value is 6.

     RSTP Status:

       These key-value pairs report the status of 802.1D-2004. They are
       present only if RSTP is enabled (via the rstp_enable column).

       rstp_status : rstp_bridge_id: optional string
              The bridge ID used in rapid spanning tree advertisements, in
              the form x.yyy.zzzzzzzzzzzz where x is the RSTP priority, the
              ys are a locally assigned system ID extension, the zs are the
              STP system ID, and each x, y, or z is a hex digit.

       rstp_status : rstp_root_id: optional string
              The root of this spanning tree, in the same form as
              rstp_status:rstp_bridge_id. If this bridge is the root, this
              will have the same value as rstp_status:rstp_bridge_id,
              otherwise it will differ.

       rstp_status : rstp_root_path_cost: optional string, containing an
       integer, at least 0
              The path cost of reaching the root. A lower number is better.
              The value is 0 if this bridge is the root, otherwise it is
              higher.

       rstp_status : rstp_designated_id: optional string
              The RSTP designated ID, in the same form as
              rstp_status:rstp_bridge_id.

       rstp_status : rstp_designated_port_id: optional string
              The RSTP designated port ID, as a 4-digit hex number.

       rstp_status : rstp_bridge_port_id: optional string
              The RSTP bridge port ID, as a 4-digit hex number.

     Multicast Snooping Configuration:

       Multicast snooping (RFC 4541) monitors the Internet Group Management
       Protocol (IGMP) and Multicast Listener Discovery traffic between
       hosts and multicast routers. The switch uses what IGMP and MLD
       snooping learns to forward multicast traffic only to interfaces that
       are connected to interested receivers. Currently it supports IGMPv1,
       IGMPv2, IGMPv3, MLDv1 and MLDv2 protocols.

       mcast_snooping_enable: boolean
              Enable multicast snooping on the bridge. For now, the default
              is disabled.

     Other Features:

       datapath_type: string
              Name of datapath provider. The kernel datapath has type
              system. The userspace datapath has type netdev. A manager may
              refer to the datapath_types column of the Open_vSwitch table
              for a list of the types accepted by this Open vSwitch
              instance.

       external_ids : bridge-id: optional string
              A unique identifier of the bridge. On Citrix XenServer this
              will commonly be the same as external_ids:xs-network-uuids.

       external_ids : xs-network-uuids: optional string
              Semicolon-delimited set of universally unique identifier(s)
              for the network with which this bridge is associated on a
              Citrix XenServer host. The network identifiers are RFC 4122
              UUIDs as displayed by, e.g., xe network-list.

       other_config : hwaddr: optional string
              An Ethernet address in the form xx:xx:xx:xx:xx:xx to set the
              hardware address of the local port and influence the datapath
              ID.

       other_config : forward-bpdu: optional string, either true or false
              Controls forwarding of BPDUs and other network control frames
              when NORMAL action is invoked. When this option is false or
              unset, frames with reserved Ethernet addresses (see table
              below) will not be forwarded. When this option is true, such
              frames will not be treated specially.

              The above general rule has the following exceptions:

              ·      If STP is enabled on the bridge (see the stp_enable
                     column in the Bridge table), the bridge processes all
                     received STP packets and never passes them to OpenFlow
                     or forwards them. This is true even if STP is disabled
                     on an individual port.

              ·      If LLDP is enabled on an interface (see the lldp column
                     in the Interface table), the interface processes
                     received LLDP packets and never passes them to OpenFlow
                     or forwards them.

              Set this option to true if the Open vSwitch bridge connects
              different Ethernet networks and is not configured to
              participate in STP.

              This option affects packets with the following destination MAC
              addresses:

              01:80:c2:00:00:00
                     IEEE 802.1D Spanning Tree Protocol (STP).

              01:80:c2:00:00:01
                     IEEE Pause frame.

              01:80:c2:00:00:0x
                     Other reserved protocols.

              00:e0:2b:00:00:00
                     Extreme Discovery Protocol (EDP).

              00:e0:2b:00:00:04 and 00:e0:2b:00:00:06
                     Ethernet Automatic Protection Switching (EAPS).

              01:00:0c:cc:cc:cc
                     Cisco Discovery Protocol (CDP), VLAN Trunking Protocol
                     (VTP), Dynamic Trunking Protocol (DTP), Port
                     Aggregation Protocol (PAgP), and others.

              01:00:0c:cc:cc:cd
                     Cisco Shared Spanning Tree Protocol PVSTP+.

              01:00:0c:cd:cd:cd
                     Cisco STP Uplink Fast.

              01:00:0c:00:00:00
                     Cisco Inter Switch Link.

              01:00:0c:cc:cc:cx
                     Cisco CFM.

       other_config : mac-aging-time: optional string, containing an
       integer, at least 1
              The maximum number of seconds to retain a MAC learning entry
              for which no packets have been seen. The default is currently
              300 seconds (5 minutes). The value, if specified, is forced
              into a reasonable range, currently 15 to 3600 seconds.

              A short MAC aging time allows a network to more quickly detect
              that a host is no longer connected to a switch port. However,
              it also makes it more likely that packets will be flooded
              unnecessarily, when they are addressed to a connected host
              that rarely transmits packets. To reduce the incidence of
              unnecessary flooding, use a MAC aging time longer than the
              maximum interval at which a host will ordinarily transmit
              packets.

       other_config : mac-table-size: optional string, containing an
       integer, at least 1
              The maximum number of MAC addresses to learn. The default is
              currently 2048. The value, if specified, is forced into a
              reasonable range, currently 10 to 1,000,000.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Port TABLE         top

       A port within a Bridge.

       Most commonly, a port has exactly one ``interface,’’ pointed to by
       its interfaces column. Such a port logically corresponds to a port on
       a physical Ethernet switch. A port with more than one interface is a
       ``bonded port’’ (see Bonding Configuration).

       Some properties that one might think as belonging to a port are
       actually part of the port’s Interface members.

   Summary:
       name                          immutable string (must be unique within
                                     table)
       interfaces                    set of 1 or more Interfaces
       VLAN Configuration:
         vlan_mode                   optional string, one of access,
                                     dot1q-tunnel, native-tagged,
                                     native-untagged, or trunk
         tag                         optional integer, in range 0 to 4,095
         trunks                      set of up to 4,096 integers, in range 0
                                     to 4,095
         cvlans                      set of up to 4,096 integers, in range 0
                                     to 4,095
         other_config : qinq-ethtype
                                     optional string, either 802.1ad or
                                     802.1q
         other_config : priority-tags
                                     optional string, either true or false
       Bonding Configuration:
         bond_mode                   optional string, one of active-backup,
                                     balance-slb, or balance-tcp
         other_config : bond-hash-basis
                                     optional string, containing an integer
         Link Failure Detection:
            other_config : bond-detect-mode
                                     optional string, either carrier or
                                     miimon
            other_config : bond-miimon-interval
                                     optional string, containing an integer
            bond_updelay             integer
            bond_downdelay           integer
         LACP Configuration:
            lacp                     optional string, one of active, off, or
                                     passive
            other_config : lacp-system-id
                                     optional string
            other_config : lacp-system-priority
                                     optional string, containing an integer,
                                     in range 1 to 65,535
            other_config : lacp-time optional string, either fast or slow
            other_config : lacp-fallback-ab
                                     optional string, either true or false
         Rebalancing Configuration:
            other_config : bond-rebalance-interval
                                     optional string, containing an integer,
                                     in range 0 to 10,000
         bond_fake_iface             boolean
       Spanning Tree Protocol:
         STP Configuration:
            other_config : stp-enable
                                     optional string, either true or false
            other_config : stp-port-num
                                     optional string, containing an integer,
                                     in range 1 to 255
            other_config : stp-port-priority
                                     optional string, containing an integer,
                                     in range 0 to 255
            other_config : stp-path-cost
                                     optional string, containing an integer,
                                     in range 0 to 65,535
         STP Status:
            status : stp_port_id     optional string
            status : stp_state       optional string, one of blocking,
                                     disabled, forwarding, learning, or
                                     listening
            status : stp_sec_in_state
                                     optional string, containing an integer,
                                     at least 0
            status : stp_role        optional string, one of alternate,
                                     designated, or root
       Rapid Spanning Tree Protocol:
         RSTP Configuration:
            other_config : rstp-enable
                                     optional string, either true or false
            other_config : rstp-port-priority
                                     optional string, containing an integer,
                                     in range 0 to 240
            other_config : rstp-port-num
                                     optional string, containing an integer,
                                     in range 1 to 4,095
            other_config : rstp-port-path-cost
                                     optional string, containing an integer
            other_config : rstp-port-admin-edge
                                     optional string, either true or false
            other_config : rstp-port-auto-edge
                                     optional string, either true or false
            other_config : rstp-port-mcheck
                                     optional string, either true or false
         RSTP Status:
            rstp_status : rstp_port_id
                                     optional string
            rstp_status : rstp_port_role
                                     optional string, one of Alternate,
                                     Backup, Designated, Disabled, or Root
            rstp_status : rstp_port_state
                                     optional string, one of Disabled,
                                     Discarding, Forwarding, or Learning
            rstp_status : rstp_designated_bridge_id
                                     optional string
            rstp_status : rstp_designated_port_id
                                     optional string
            rstp_status : rstp_designated_path_cost
                                     optional string, containing an integer
         RSTP Statistics:
            rstp_statistics : rstp_tx_count
                                     optional integer
            rstp_statistics : rstp_rx_count
                                     optional integer
            rstp_statistics : rstp_error_count
                                     optional integer
            rstp_statistics : rstp_uptime
                                     optional integer
       Multicast Snooping:
         other_config : mcast-snooping-flood
                                     optional string, either true or false
         other_config : mcast-snooping-flood-reports
                                     optional string, either true or false
       Other Features:
         qos                         optional QoS
         mac                         optional string
         fake_bridge                 boolean
         protected                   boolean
         external_ids : fake-bridge-id-*
                                     optional string
         other_config : transient    optional string, either true or false
       bond_active_slave             optional string
       Port Statistics:
         Statistics: STP transmit and receive counters:
            statistics : stp_tx_count
                                     optional integer
            statistics : stp_rx_count
                                     optional integer
            statistics : stp_error_count
                                     optional integer
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
       name: immutable string (must be unique within table)
              Port name. For a non-bonded port, this should be the same as
              its interface’s name. Port names must otherwise be unique
              among the names of ports, interfaces, and bridges on a host.
              Because port and interfaces names are usually the same, the
              restrictions on the name column in the Interface table,
              particularly on length, also apply to port names. Refer to the
              documentation for Interface names for details.

       interfaces: set of 1 or more Interfaces
              The port’s interfaces. If there is more than one, this is a
              bonded Port.

     VLAN Configuration:

       In short, a VLAN (short for ``virtual LAN’’) is a way to partition a
       single switch into multiple switches. VLANs can be confusing, so for
       an introduction, please refer to the question ``What’s a VLAN?’’ in
       the Open vSwitch FAQ.

       A VLAN is sometimes encoded into a packet using a 802.1Q or 802.1ad
       VLAN header, but every packet is part of some VLAN whether or not it
       is encoded in the packet. (A packet that appears to have no VLAN is
       part of VLAN 0, by default.) As a result, it’s useful to think of a
       VLAN as a metadata property of a packet, separate from how the VLAN
       is encoded. For a given port, this column determines how the encoding
       of a packet that ingresses or egresses the port maps to the packet’s
       VLAN. When a packet enters the switch, its VLAN is determined based
       on its setting in this column and its VLAN headers, if any, and then,
       conceptually, the VLAN headers are then stripped off. Conversely,
       when a packet exits the switch, its VLAN and the settings in this
       column determine what VLAN headers, if any, are pushed onto the
       packet before it egresses the port.

       The VLAN configuration in this column affects Open vSwitch only when
       it is doing ``normal switching.’’ It does not affect flows set up by
       an OpenFlow controller, outside of the OpenFlow ``normal action.’’

       Bridge ports support the following types of VLAN configuration:

              trunk  A trunk port carries packets on one or more specified
                     VLANs specified in the trunks column (often, on every
                     VLAN). A packet that ingresses on a trunk port is in
                     the VLAN specified in its 802.1Q header, or VLAN 0 if
                     the packet has no 802.1Q header. A packet that egresses
                     through a trunk port will have an 802.1Q header if it
                     has a nonzero VLAN ID.

                     Any packet that ingresses on a trunk port tagged with a
                     VLAN that the port does not trunk is dropped.

              access An access port carries packets on exactly one VLAN
                     specified in the tag column. Packets egressing on an
                     access port have no 802.1Q header.

                     Any packet with an 802.1Q header with a nonzero VLAN ID
                     that ingresses on an access port is dropped, regardless
                     of whether the VLAN ID in the header is the access
                     port’s VLAN ID.

              native-tagged
                     A native-tagged port resembles a trunk port, with the
                     exception that a packet without an 802.1Q header that
                     ingresses on a native-tagged port is in the ``native
                     VLAN’’ (specified in the tag column).

              native-untagged
                     A native-untagged port resembles a native-tagged port,
                     with the exception that a packet that egresses on a
                     native-untagged port in the native VLAN will not have
                     an 802.1Q header.

              dot1q-tunnel
                     A dot1q-tunnel port is somewhat like an access port.
                     Like an access port, it carries packets on the single
                     VLAN specified in the tag column and this VLAN, called
                     the service VLAN, does not appear in an 802.1Q header
                     for packets that ingress or egress on the port. The
                     main difference lies in the behavior when packets that
                     include a 802.1Q header ingress on the port. Whereas an
                     access port drops such packets, a dot1q-tunnel port
                     treats these as double-tagged with the outer service
                     VLAN tag and the inner customer VLAN taken from the
                     802.1Q header. Correspondingly, to egress on the port,
                     a packet outer VLAN (or only VLAN) must be tag, which
                     is removed before egress, which exposes the inner
                     (customer) VLAN if one is present.

                     If cvlans is set, only allows packets in the specified
                     customer VLANs.

       A packet will only egress through bridge ports that carry the VLAN of
       the packet, as described by the rules above.

       vlan_mode: optional string, one of access, dot1q-tunnel,
       native-tagged, native-untagged, or trunk
              The VLAN mode of the port, as described above. When this
              column is empty, a default mode is selected as follows:

              ·      If tag contains a value, the port is an access port.
                     The trunks column should be empty.

              ·      Otherwise, the port is a trunk port. The trunks column
                     value is honored if it is present.

       tag: optional integer, in range 0 to 4,095
              For an access port, the port’s implicitly tagged VLAN. For a
              native-tagged or native-untagged port, the port’s native VLAN.
              Must be empty if this is a trunk port.

       trunks: set of up to 4,096 integers, in range 0 to 4,095
              For a trunk, native-tagged, or native-untagged port, the
              802.1Q VLAN or VLANs that this port trunks; if it is empty,
              then the port trunks all VLANs. Must be empty if this is an
              access port.

              A native-tagged or native-untagged port always trunks its
              native VLAN, regardless of whether trunks includes that VLAN.

       cvlans: set of up to 4,096 integers, in range 0 to 4,095
              For a dot1q-tunnel port, the customer VLANs that this port
              includes. If this is empty, the port includes all customer
              VLANs.

              For other kinds of ports, this setting is ignored.

       other_config : qinq-ethtype: optional string, either 802.1ad or
       802.1q
              For a dot1q-tunnel port, this is the TPID for the service tag,
              that is, for the 802.1Q header that contains the service VLAN
              ID. Because packets that actually ingress and egress a dot1q-
              tunnel port do not include an 802.1Q header for the service
              VLAN, this does not affect packets on the dot1q-tunnel port
              itself. Rather, it determines the service VLAN for a packet
              that ingresses on a dot1q-tunnel port and egresses on a trunk
              port.

              The value 802.1ad specifies TPID 0x88a8, which is also the
              default if the setting is omitted. The value 802.1q specifies
              TPID 0x8100.

              For other kinds of ports, this setting is ignored.

       other_config : priority-tags: optional string, either true or false
              An 802.1Q header contains two important pieces of information:
              a VLAN ID and a priority. A frame with a zero VLAN ID, called
              a ``priority-tagged’’ frame, is supposed to be treated the
              same way as a frame without an 802.1Q header at all (except
              for the priority).

              However, some network elements ignore any frame that has
              802.1Q header at all, even when the VLAN ID is zero.
              Therefore, by default Open vSwitch does not output priority-
              tagged frames, instead omitting the 802.1Q header entirely if
              the VLAN ID is zero. Set this key to true to enable priority-
              tagged frames on a port.

              Regardless of this setting, Open vSwitch omits the 802.1Q
              header on output if both the VLAN ID and priority would be
              zero.

              All frames output to native-tagged ports have a nonzero VLAN
              ID, so this setting is not meaningful on native-tagged ports.

     Bonding Configuration:

       A port that has more than one interface is a ``bonded port.’’ Bonding
       allows for load balancing and fail-over.

       The following types of bonding will work with any kind of upstream
       switch. On the upstream switch, do not configure the interfaces as a
       bond:

              balance-slb
                     Balances flows among slaves based on source MAC address
                     and output VLAN, with periodic rebalancing as traffic
                     patterns change.

              active-backup
                     Assigns all flows to one slave, failing over to a
                     backup slave when the active slave is disabled. This is
                     the only bonding mode in which interfaces may be
                     plugged into different upstream switches.

       The following modes require the upstream switch to support 802.3ad
       with successful LACP negotiation. If LACP negotiation fails and
       other-config:lacp-fallback-ab is true, then active-backup mode is
       used:

              balance-tcp
                     Balances flows among slaves based on L3 and L4 protocol
                     information such as IP addresses and TCP/UDP ports.

       These columns apply only to bonded ports. Their values are otherwise
       ignored.

       bond_mode: optional string, one of active-backup, balance-slb, or
       balance-tcp
              The type of bonding used for a bonded port. Defaults to
              active-backup if unset.

       other_config : bond-hash-basis: optional string, containing an
       integer
              An integer hashed along with flows when choosing output slaves
              in load balanced bonds. When changed, all flows will be
              assigned different hash values possibly causing slave
              selection decisions to change. Does not affect bonding modes
              which do not employ load balancing such as active-backup.

     Link Failure Detection:

       An important part of link bonding is detecting that links are down so
       that they may be disabled. These settings determine how Open vSwitch
       detects link failure.

       other_config : bond-detect-mode: optional string, either carrier or
       miimon
              The means used to detect link failures. Defaults to carrier
              which uses each interface’s carrier to detect failures. When
              set to miimon, will check for failures by polling each
              interface’s MII.

       other_config : bond-miimon-interval: optional string, containing an
       integer
              The interval, in milliseconds, between successive attempts to
              poll each interface’s MII. Relevant only when
              other_config:bond-detect-mode is miimon.

       bond_updelay: integer
              The number of milliseconds for which the link must stay up on
              an interface before the interface is considered to be up.
              Specify 0 to enable the interface immediately.

              This setting is honored only when at least one bonded
              interface is already enabled. When no interfaces are enabled,
              then the first bond interface to come up is enabled
              immediately.

       bond_downdelay: integer
              The number of milliseconds for which the link must stay down
              on an interface before the interface is considered to be down.
              Specify 0 to disable the interface immediately.

     LACP Configuration:

       LACP, the Link Aggregation Control Protocol, is an IEEE standard that
       allows switches to automatically detect that they are connected by
       multiple links and aggregate across those links. These settings
       control LACP behavior.

       lacp: optional string, one of active, off, or passive
              Configures LACP on this port. LACP allows directly connected
              switches to negotiate which links may be bonded. LACP may be
              enabled on non-bonded ports for the benefit of any switches
              they may be connected to. active ports are allowed to initiate
              LACP negotiations. passive ports are allowed to participate in
              LACP negotiations initiated by a remote switch, but not
              allowed to initiate such negotiations themselves. If LACP is
              enabled on a port whose partner switch does not support LACP,
              the bond will be disabled, unless other-config:lacp-fallback-
              ab is set to true. Defaults to off if unset.

       other_config : lacp-system-id: optional string
              The LACP system ID of this Port. The system ID of a LACP bond
              is used to identify itself to its partners. Must be a nonzero
              MAC address. Defaults to the bridge Ethernet address if unset.

       other_config : lacp-system-priority: optional string, containing an
       integer, in range 1 to 65,535
              The LACP system priority of this Port. In LACP negotiations,
              link status decisions are made by the system with the
              numerically lower priority.

       other_config : lacp-time: optional string, either fast or slow
              The LACP timing which should be used on this Port. By default
              slow is used. When configured to be fast LACP heartbeats are
              requested at a rate of once per second causing connectivity
              problems to be detected more quickly. In slow mode, heartbeats
              are requested at a rate of once every 30 seconds.

       other_config : lacp-fallback-ab: optional string, either true or
       false
              Determines the behavior of openvswitch bond in LACP mode. If
              the partner switch does not support LACP, setting this option
              to true allows openvswitch to fallback to active-backup. If
              the option is set to false, the bond will be disabled. In both
              the cases, once the partner switch is configured to LACP mode,
              the bond will use LACP.

     Rebalancing Configuration:

       These settings control behavior when a bond is in balance-slb or
       balance-tcp mode.

       other_config : bond-rebalance-interval: optional string, containing
       an integer, in range 0 to 10,000
              For a load balanced bonded port, the number of milliseconds
              between successive attempts to rebalance the bond, that is, to
              move flows from one interface on the bond to another in an
              attempt to keep usage of each interface roughly equal. If
              zero, load balancing is disabled on the bond (link failure
              still cause flows to move). If less than 1000ms, the rebalance
              interval will be 1000ms.

       bond_fake_iface: boolean
              For a bonded port, whether to create a fake internal interface
              with the name of the port. Use only for compatibility with
              legacy software that requires this.

     Spanning Tree Protocol:

       The configuration here is only meaningful, and the status is only
       populated, when 802.1D-1998 Spanning Tree Protocol is enabled on the
       port’s Bridge with its stp_enable column.

     STP Configuration:

       other_config : stp-enable: optional string, either true or false
              When STP is enabled on a bridge, it is enabled by default on
              all of the bridge’s ports except bond, internal, and mirror
              ports (which do not work with STP). If this column’s value is
              false, STP is disabled on the port.

       other_config : stp-port-num: optional string, containing an integer,
       in range 1 to 255
              The port number used for the lower 8 bits of the port-id. By
              default, the numbers will be assigned automatically. If any
              port’s number is manually configured on a bridge, then they
              must all be.

       other_config : stp-port-priority: optional string, containing an
       integer, in range 0 to 255
              The port’s relative priority value for determining the root
              port (the upper 8 bits of the port-id). A port with a lower
              port-id will be chosen as the root port. By default, the
              priority is 0x80.

       other_config : stp-path-cost: optional string, containing an integer,
       in range 0 to 65,535
              Spanning tree path cost for the port. A lower number indicates
              a faster link. By default, the cost is based on the maximum
              speed of the link.

     STP Status:

       status : stp_port_id: optional string
              The port ID used in spanning tree advertisements for this
              port, as 4 hex digits. Configuring the port ID is described in
              the stp-port-num and stp-port-priority keys of the
              other_config section earlier.

       status : stp_state: optional string, one of blocking, disabled,
       forwarding, learning, or listening
              STP state of the port.

       status : stp_sec_in_state: optional string, containing an integer, at
       least 0
              The amount of time this port has been in the current STP
              state, in seconds.

       status : stp_role: optional string, one of alternate, designated, or
       root
              STP role of the port.

     Rapid Spanning Tree Protocol:

       The configuration here is only meaningful, and the status and
       statistics are only populated, when 802.1D-1998 Spanning Tree
       Protocol is enabled on the port’s Bridge with its stp_enable column.

     RSTP Configuration:

       other_config : rstp-enable: optional string, either true or false
              When RSTP is enabled on a bridge, it is enabled by default on
              all of the bridge’s ports except bond, internal, and mirror
              ports (which do not work with RSTP). If this column’s value is
              false, RSTP is disabled on the port.

       other_config : rstp-port-priority: optional string, containing an
       integer, in range 0 to 240
              The port’s relative priority value for determining the root
              port, in multiples of 16. By default, the port priority is
              0x80 (128). Any value in the lower 4 bits is rounded off. The
              significant upper 4 bits become the upper 4 bits of the port-
              id. A port with the lowest port-id is elected as the root.

       other_config : rstp-port-num: optional string, containing an integer,
       in range 1 to 4,095
              The local RSTP port number, used as the lower 12 bits of the
              port-id. By default the port numbers are assigned
              automatically, and typically may not correspond to the
              OpenFlow port numbers. A port with the lowest port-id is
              elected as the root.

       other_config : rstp-port-path-cost: optional string, containing an
       integer
              The port path cost. The Port’s contribution, when it is the
              Root Port, to the Root Path Cost for the Bridge. By default
              the cost is automatically calculated from the port’s speed.

       other_config : rstp-port-admin-edge: optional string, either true or
       false
              The admin edge port parameter for the Port. Default is false.

       other_config : rstp-port-auto-edge: optional string, either true or
       false
              The auto edge port parameter for the Port. Default is true.

       other_config : rstp-port-mcheck: optional string, either true or
       false
              The mcheck port parameter for the Port. Default is false. May
              be set to force the Port Protocol Migration state machine to
              transmit RST BPDUs for a MigrateTime period, to test whether
              all STP Bridges on the attached LAN have been removed and the
              Port can continue to transmit RSTP BPDUs. Setting mcheck has
              no effect if the Bridge is operating in STP Compatibility
              mode.

              Changing the value from true to false has no effect, but needs
              to be done if this behavior is to be triggered again by
              subsequently changing the value from false to true.

     RSTP Status:

       rstp_status : rstp_port_id: optional string
              The port ID used in spanning tree advertisements for this
              port, as 4 hex digits. Configuring the port ID is described in
              the rstp-port-num and rstp-port-priority keys of the
              other_config section earlier.

       rstp_status : rstp_port_role: optional string, one of Alternate,
       Backup, Designated, Disabled, or Root
              RSTP role of the port.

       rstp_status : rstp_port_state: optional string, one of Disabled,
       Discarding, Forwarding, or Learning
              RSTP state of the port.

       rstp_status : rstp_designated_bridge_id: optional string
              The port’s RSTP designated bridge ID, in the same form as
              rstp_status:rstp_bridge_id in the Bridge table.

       rstp_status : rstp_designated_port_id: optional string
              The port’s RSTP designated port ID, as 4 hex digits.

       rstp_status : rstp_designated_path_cost: optional string, containing
       an integer
              The port’s RSTP designated path cost. Lower is better.

     RSTP Statistics:

       rstp_statistics : rstp_tx_count: optional integer
              Number of RSTP BPDUs transmitted through this port.

       rstp_statistics : rstp_rx_count: optional integer
              Number of valid RSTP BPDUs received by this port.

       rstp_statistics : rstp_error_count: optional integer
              Number of invalid RSTP BPDUs received by this port.

       rstp_statistics : rstp_uptime: optional integer
              The duration covered by the other RSTP statistics, in seconds.

     Multicast Snooping:

       other_config : mcast-snooping-flood: optional string, either true or
       false
              If set to true, multicast packets (except Reports) are
              unconditionally forwarded to the specific port.

       other_config : mcast-snooping-flood-reports: optional string, either
       true or false
              If set to true, multicast Reports are unconditionally
              forwarded to the specific port.

     Other Features:

       qos: optional QoS
              Quality of Service configuration for this port.

       mac: optional string
              The MAC address to use for this port for the purpose of
              choosing the bridge’s MAC address. This column does not
              necessarily reflect the port’s actual MAC address, nor will
              setting it change the port’s actual MAC address.

       fake_bridge: boolean
              Does this port represent a sub-bridge for its tagged VLAN
              within the Bridge? See ovs-vsctl(8) for more information.

       protected: boolean
              The protected ports feature allows certain ports to be
              designated as protected. Traffic between protected ports is
              blocked. Protected ports can send traffic to unprotected
              ports. Unprotected ports can send traffic to any port. Default
              is false.

       external_ids : fake-bridge-id-*: optional string
              External IDs for a fake bridge (see the fake_bridge column)
              are defined by prefixing a Bridge external_ids key with
              fake-bridge-, e.g. fake-bridge-xs-network-uuids.

       other_config : transient: optional string, either true or false
              If set to true, the port will be removed when ovs-ctl start
              --delete-transient-ports is used.

       bond_active_slave: optional string
              For a bonded port, record the mac address of the current
              active slave.

     Port Statistics:

       Key-value pairs that report port statistics. The update period is
       controlled by other_config:stats-update-interval in the Open_vSwitch
       table.

     Statistics: STP transmit and receive counters:

       statistics : stp_tx_count: optional integer
              Number of STP BPDUs sent on this port by the spanning tree
              library.

       statistics : stp_rx_count: optional integer
              Number of STP BPDUs received on this port and accepted by the
              spanning tree library.

       statistics : stp_error_count: optional integer
              Number of bad STP BPDUs received on this port. Bad BPDUs
              include runt packets and those with an unexpected protocol ID.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Interface TABLE         top

       An interface within a Port.

   Summary:
       Core Features:
         name                        immutable string (must be unique within
                                     table)
         ifindex                     optional integer, in range 0 to
                                     4,294,967,295
         mac_in_use                  optional string
         mac                         optional string
         error                       optional string
         OpenFlow Port Number:
            ofport                   optional integer
            ofport_request           optional integer, in range 1 to 65,279
       System-Specific Details:
         type                        string
       Tunnel Options:
         options : remote_ip         optional string
         options : local_ip          optional string
         options : in_key            optional string
         options : out_key           optional string
         options : dst_port          optional string
         options : key               optional string
         options : tos               optional string
         options : ttl               optional string
         options : df_default        optional string, either true or false
         options : egress_pkt_mark   optional string
         Tunnel Options: lisp only:
            options : packet_type    optional string, either legacy_l3 or
                                     ptap
         Tunnel Options: vxlan only:
            options : exts           optional string
            options : packet_type    optional string, one of legacy_l2,
                                     legacy_l3, or ptap
         Tunnel Options: gre only:
            options : packet_type    optional string, one of legacy_l2,
                                     legacy_l3, or ptap
         Tunnel Options: gre, geneve, and vxlan:
            options : csum           optional string, either true or false
       Patch Options:
         options : peer              optional string
       PMD (Poll Mode Driver) Options:
         options : n_rxq             optional string, containing an integer,
                                     at least 1
         options : dpdk-devargs      optional string
         other_config : pmd-rxq-affinity
                                     optional string
         options : vhost-server-path
                                     optional string
         options : n_rxq_desc        optional string, containing an integer,
                                     in range 1 to 4,096
         options : n_txq_desc        optional string, containing an integer,
                                     in range 1 to 4,096
       MTU:
         mtu                         optional integer
         mtu_request                 optional integer, at least 1
       Interface Status:
         admin_state                 optional string, either down or up
         link_state                  optional string, either down or up
         link_resets                 optional integer
         link_speed                  optional integer
         duplex                      optional string, either full or half
         lacp_current                optional boolean
         status                      map of string-string pairs
         status : driver_name        optional string
         status : driver_version     optional string
         status : firmware_version   optional string
         status : source_ip          optional string
         status : tunnel_egress_iface
                                     optional string
         status : tunnel_egress_iface_carrier
                                     optional string, either down or up
       Statistics:
         Statistics: Successful transmit and receive counters:
            statistics : rx_packets  optional integer
            statistics : rx_bytes    optional integer
            statistics : tx_packets  optional integer
            statistics : tx_bytes    optional integer
         Statistics: Receive errors:
            statistics : rx_dropped  optional integer
            statistics : rx_frame_err
                                     optional integer
            statistics : rx_over_err optional integer
            statistics : rx_crc_err  optional integer
            statistics : rx_errors   optional integer
         Statistics: Transmit errors:
            statistics : tx_dropped  optional integer
            statistics : collisions  optional integer
            statistics : tx_errors   optional integer
       Ingress Policing:
         ingress_policing_rate       integer, at least 0
         ingress_policing_burst      integer, at least 0
       Bidirectional Forwarding Detection (BFD):
         BFD Configuration:
            bfd : enable             optional string, either true or false
            bfd : min_rx             optional string, containing an integer,
                                     at least 1
            bfd : min_tx             optional string, containing an integer,
                                     at least 1
            bfd : decay_min_rx       optional string, containing an integer
            bfd : forwarding_if_rx   optional string, either true or false
            bfd : cpath_down         optional string, either true or false
            bfd : check_tnl_key      optional string, either true or false
            bfd : bfd_local_src_mac  optional string
            bfd : bfd_local_dst_mac  optional string
            bfd : bfd_remote_dst_mac optional string
            bfd : bfd_src_ip         optional string
            bfd : bfd_dst_ip         optional string
            bfd : oam                optional string
            bfd : mult               optional string, containing an integer,
                                     in range 1 to 255
         BFD Status:
            bfd_status : state       optional string, one of admin_down,
                                     down, init, or up
            bfd_status : forwarding  optional string, either true or false
            bfd_status : diagnostic  optional string
            bfd_status : remote_state
                                     optional string, one of admin_down,
                                     down, init, or up
            bfd_status : remote_diagnostic
                                     optional string
            bfd_status : flap_count  optional string, containing an integer,
                                     at least 0
       Connectivity Fault Management:
         cfm_mpid                    optional integer
         cfm_flap_count              optional integer
         cfm_fault                   optional boolean
         cfm_fault_status : recv     none
         cfm_fault_status : rdi      none
         cfm_fault_status : maid     none
         cfm_fault_status : loopback
                                     none
         cfm_fault_status : overflow
                                     none
         cfm_fault_status : override
                                     none
         cfm_fault_status : interval
                                     none
         cfm_remote_opstate          optional string, either down or up
         cfm_health                  optional integer, in range 0 to 100
         cfm_remote_mpids            set of integers
         other_config : cfm_interval
                                     optional string, containing an integer
         other_config : cfm_extended
                                     optional string, either true or false
         other_config : cfm_demand   optional string, either true or false
         other_config : cfm_opstate  optional string, either down or up
         other_config : cfm_ccm_vlan
                                     optional string, containing an integer,
                                     in range 1 to 4,095
         other_config : cfm_ccm_pcp  optional string, containing an integer,
                                     in range 1 to 7
       Bonding Configuration:
         other_config : lacp-port-id
                                     optional string, containing an integer,
                                     in range 1 to 65,535
         other_config : lacp-port-priority
                                     optional string, containing an integer,
                                     in range 1 to 65,535
         other_config : lacp-aggregation-key
                                     optional string, containing an integer,
                                     in range 1 to 65,535
       Virtual Machine Identifiers:
         external_ids : attached-mac
                                     optional string
         external_ids : iface-id     optional string
         external_ids : iface-status
                                     optional string, either active or
                                     inactive
         external_ids : xs-vif-uuid  optional string
         external_ids : xs-network-uuid
                                     optional string
         external_ids : vm-id        optional string
         external_ids : xs-vm-uuid   optional string
       Auto Attach Configuration:
         lldp : enable               optional string, either true or false
       Flow control Configuration:
         options : rx-flow-ctrl      optional string, either true or false
         options : tx-flow-ctrl      optional string, either true or false
         options : flow-ctrl-autoneg
                                     optional string, either true or false
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
     Core Features:

       name: immutable string (must be unique within table)
              Interface name. Should be alphanumeric. For non-bonded port,
              this should be the same as the port name. It must otherwise be
              unique among the names of ports, interfaces, and bridges on a
              host.

              The maximum length of an interface name depends on the
              underlying datapath:

              ·      The names of interfaces implemented as Linux and BSD
                     network devices, including interfaces with type
                     internal, tap, or system plus the different types of
                     tunnel ports, are limited to 15 bytes. Windows limits
                     these names to 255 bytes.

              ·      The names of patch ports are not used in the underlying
                     datapath, so operating system restrictions do not
                     apply. Thus, they may have arbitrary length.

              Regardless of other restrictions, OpenFlow only supports
              15-byte names, which means that ovs-ofctl and OpenFlow
              controllers will show names truncated to 15 bytes.

       ifindex: optional integer, in range 0 to 4,294,967,295
              A positive interface index as defined for SNMP MIB-II in RFCs
              1213 and 2863, if the interface has one, otherwise 0. The
              ifindex is useful for seamless integration with protocols such
              as SNMP and sFlow.

       mac_in_use: optional string
              The MAC address in use by this interface.

       mac: optional string
              Ethernet address to set for this interface. If unset then the
              default MAC address is used:

              ·      For the local interface, the default is the lowest-
                     numbered MAC address among the other bridge ports,
                     either the value of the mac in its Port record, if set,
                     or its actual MAC (for bonded ports, the MAC of its
                     slave whose name is first in alphabetical order).
                     Internal ports and bridge ports that are used as port
                     mirroring destinations (see the Mirror table) are
                     ignored.

              ·      For other internal interfaces, the default MAC is
                     randomly generated.

              ·      External interfaces typically have a MAC address
                     associated with their hardware.

              Some interfaces may not have a software-controllable MAC
              address.

       error: optional string
              If the configuration of the port failed, as indicated by -1 in
              ofport, Open vSwitch sets this column to an error description
              in human readable form. Otherwise, Open vSwitch clears this
              column.

     OpenFlow Port Number:

       When a client adds a new interface, Open vSwitch chooses an OpenFlow
       port number for the new port. If the client that adds the port fills
       in ofport_request, then Open vSwitch tries to use its value as the
       OpenFlow port number. Otherwise, or if the requested port number is
       already in use or cannot be used for another reason, Open vSwitch
       automatically assigns a free port number. Regardless of how the port
       number was obtained, Open vSwitch then reports in ofport the port
       number actually assigned.

       Open vSwitch limits the port numbers that it automatically assigns to
       the range 1 through 32,767, inclusive. Controllers therefore have
       free use of ports 32,768 and up.

       ofport: optional integer
              OpenFlow port number for this interface. Open vSwitch sets
              this column’s value, so other clients should treat it as read-
              only.

              The OpenFlow ``local’’ port (OFPP_LOCAL) is 65,534. The other
              valid port numbers are in the range 1 to 65,279, inclusive.
              Value -1 indicates an error adding the interface.

       ofport_request: optional integer, in range 1 to 65,279
              Requested OpenFlow port number for this interface.

              A client should ideally set this column’s value in the same
              database transaction that it uses to create the interface.
              Open vSwitch version 2.1 and later will honor a later request
              for a specific port number, althuogh it might confuse some
              controllers: OpenFlow does not have a way to announce a port
              number change, so Open vSwitch represents it over OpenFlow as
              a port deletion followed immediately by a port addition.

              If ofport_request is set or changed to some other port’s
              automatically assigned port number, Open vSwitch chooses a new
              port number for the latter port.

     System-Specific Details:

       type: string
              The interface type. The types supported by a particular
              instance of Open vSwitch are listed in the iface_types column
              in the Open_vSwitch table. The following types are defined:

              system An ordinary network device, e.g. eth0 on Linux.
                     Sometimes referred to as ``external interfaces’’ since
                     they are generally connected to hardware external to
                     that on which the Open vSwitch is running. The empty
                     string is a synonym for system.

              internal
                     A simulated network device that sends and receives
                     traffic. An internal interface whose name is the same
                     as its bridge’s name is called the ``local interface.’’
                     It does not make sense to bond an internal interface,
                     so the terms ``port’’ and ``interface’’ are often used
                     imprecisely for internal interfaces.

              tap    A TUN/TAP device managed by Open vSwitch.

              geneve An Ethernet over Geneve
                     (http://tools.ietf.org/html/draft-ietf-nvo3-geneve )
                     IPv4/IPv6 tunnel. A description of how to match and set
                     Geneve options can be found in the ovs-ofctl manual
                     page.

              gre    Generic Routing Encapsulation (GRE) over IPv4/IPv6
                     tunnel, configurable to encapsulate layer 2 or layer 3
                     traffic.

              vxlan  An Ethernet tunnel over the UDP-based VXLAN protocol
                     described in RFC 7348.

                     Open vSwitch uses IANA-assigned UDP destination port
                     4789. The source port used for VXLAN traffic varies on
                     a per-flow basis and is in the ephemeral port range.

              lisp   A layer 3 tunnel over the experimental, UDP-based
                     Locator/ID Separation Protocol (RFC 6830).

                     Only IPv4 and IPv6 packets are supported by the
                     protocol, and they are sent and received without an
                     Ethernet header. Traffic to/from LISP ports is expected
                     to be configured explicitly, and the ports are not
                     intended to participate in learning based switching. As
                     such, they are always excluded from packet flooding.

              stt    The Stateless TCP Tunnel (STT) is particularly useful
                     when tunnel endpoints are in end-systems, as it
                     utilizes the capabilities of standard network interface
                     cards to improve performance. STT utilizes a TCP-like
                     header inside the IP header. It is stateless, i.e.,
                     there is no TCP connection state of any kind associated
                     with the tunnel. The TCP-like header is used to
                     leverage the capabilities of existing network interface
                     cards, but should not be interpreted as implying any
                     sort of connection state between endpoints. Since the
                     STT protocol does not engage in the usual TCP 3-way
                     handshake, so it will have difficulty traversing
                     stateful firewalls. The protocol is documented at
                     https://tools.ietf.org/html/draft-davie-stt All traffic
                     uses a default destination port of 7471.

              patch  A pair of virtual devices that act as a patch cable.

              null   An ignored interface. Deprecated and slated for removal
                     in February 2013.

     Tunnel Options:

       These options apply to interfaces with type of geneve, gre, vxlan,
       lisp and stt.

       Each tunnel must be uniquely identified by the combination of type,
       options:remote_ip, options:local_ip, and options:in_key. If two ports
       are defined that are the same except one has an optional identifier
       and the other does not, the more specific one is matched first.
       options:in_key is considered more specific than options:local_ip if a
       port defines one and another port defines the other.

       options : remote_ip: optional string
              Required. The remote tunnel endpoint, one of:

              ·      An IPv4 or IPv6 address (not a DNS name), e.g.
                     192.168.0.123. Only unicast endpoints are supported.

              ·      The word flow. The tunnel accepts packets from any
                     remote tunnel endpoint. To process only packets from a
                     specific remote tunnel endpoint, the flow entries may
                     match on the tun_src or tun_ipv6_srcfield. When sending
                     packets to a remote_ip=flow tunnel, the flow actions
                     must explicitly set the tun_dst or tun_ipv6_dst field
                     to the IP address of the desired remote tunnel
                     endpoint, e.g. with a set_field action.

              The remote tunnel endpoint for any packet received from a
              tunnel is available in the tun_src field for matching in the
              flow table.

       options : local_ip: optional string
              Optional. The tunnel destination IP that received packets must
              match. Default is to match all addresses. If specified, may be
              one of:

              ·      An IPv4/IPv6 address (not a DNS name), e.g.
                     192.168.12.3.

              ·      The word flow. The tunnel accepts packets sent to any
                     of the local IP addresses of the system running OVS. To
                     process only packets sent to a specific IP address, the
                     flow entries may match on the tun_dst or tun_ipv6_dst
                     field. When sending packets to a local_ip=flow tunnel,
                     the flow actions may explicitly set the tun_src or
                     tun_ipv6_src field to the desired IP address, e.g. with
                     a set_field action. However, while routing the tunneled
                     packet out, the local system may override the specified
                     address with the local IP address configured for the
                     outgoing system interface.

                     This option is valid only for tunnels also configured
                     with the remote_ip=flow option.

              The tunnel destination IP address for any packet received from
              a tunnel is available in the tun_dst or tun_ipv6_dst field for
              matching in the flow table.

       options : in_key: optional string
              Optional. The key that received packets must contain, one of:

              ·      0. The tunnel receives packets with no key or with a
                     key of 0. This is equivalent to specifying no
                     options:in_key at all.

              ·      A positive 24-bit (for Geneve, VXLAN, and LISP), 32-bit
                     (for GRE) or 64-bit (for STT) number. The tunnel
                     receives only packets with the specified key.

              ·      The word flow. The tunnel accepts packets with any key.
                     The key will be placed in the tun_id field for matching
                     in the flow table. The ovs-ofctl manual page contains
                     additional information about matching fields in
                     OpenFlow flows.

       options : out_key: optional string
              Optional. The key to be set on outgoing packets, one of:

              ·      0. Packets sent through the tunnel will have no key.
                     This is equivalent to specifying no options:out_key at
                     all.

              ·      A positive 24-bit (for Geneve, VXLAN and LISP), 32-bit
                     (for GRE) or 64-bit (for STT) number. Packets sent
                     through the tunnel will have the specified key.

              ·      The word flow. Packets sent through the tunnel will
                     have the key set using the set_tunnel Nicira OpenFlow
                     vendor extension (0 is used in the absence of an
                     action). The ovs-ofctl manual page contains additional
                     information about the Nicira OpenFlow vendor
                     extensions.

       options : dst_port: optional string
              Optional. The tunnel transport layer destination port, for UDP
              and TCP based tunnel protocols (Geneve, VXLAN, LISP, and STT).

       options : key: optional string
              Optional. Shorthand to set in_key and out_key at the same
              time.

       options : tos: optional string
              Optional. The value of the ToS bits to be set on the
              encapsulating packet. ToS is interpreted as DSCP and ECN bits,
              ECN part must be zero. It may also be the word inherit, in
              which case the ToS will be copied from the inner packet if it
              is IPv4 or IPv6 (otherwise it will be 0). The ECN fields are
              always inherited. Default is 0.

       options : ttl: optional string
              Optional. The TTL to be set on the encapsulating packet. It
              may also be the word inherit, in which case the TTL will be
              copied from the inner packet if it is IPv4 or IPv6 (otherwise
              it will be the system default, typically 64). Default is the
              system default TTL.

       options : df_default: optional string, either true or false
              Optional. If enabled, the Don’t Fragment bit will be set on
              tunnel outer headers to allow path MTU discovery. Default is
              enabled; set to false to disable.

       options : egress_pkt_mark: optional string
              Optional. The pkt_mark to be set on the encapsulating packet.
              This option sets packet mark for the tunnel endpoint for all
              tunnel packets including tunnel monitoring.

     Tunnel Options: lisp only:

       options : packet_type: optional string, either legacy_l3 or ptap
              A LISP tunnel sends and receives only IPv4 and IPv6 packets.
              This option controls what how the tunnel represents the
              packets that it sends and receives:

              ·      By default, or if this option is legacy_l3, the tunnel
                     represents packets as Ethernet frames for compatibility
                     with legacy OpenFlow controllers that expect this
                     behavior.

              ·      If this option is ptap, the tunnel represents packets
                     using the packet_type mechanism introduced in OpenFlow
                     1.5.

     Tunnel Options: vxlan only:

       options : exts: optional string
              Optional. Comma separated list of optional VXLAN extensions to
              enable. The following extensions are supported:

              ·      gbp: VXLAN-GBP allows to transport the group policy
                     context of a packet across the VXLAN tunnel to other
                     network peers. See the description of tun_gbp_id and
                     tun_gbp_flags in ovs-fields(7) for additional
                     information.
                     (https://tools.ietf.org/html/draft-smith-vxlan-group-policy )

              ·      gpe: Support for Generic Protocol Encapsulation in
                     accordance with IETF draft
                     https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe .
                     Without this option, a VXLAN packet always encapsulates
                     an Ethernet frame. With this option, an VXLAN packet
                     may also encapsulate an IPv4, IPv6, NSH, or MPLS
                     packet.

       options : packet_type: optional string, one of legacy_l2, legacy_l3,
       or ptap
              This option controls what types of packets the tunnel sends
              and receives and how it represents them:

              ·      By default, or if this option is legacy_l2, the tunnel
                     sends and receives only Ethernet frames.

              ·      If this option is legacy_l3, the tunnel sends and
                     receives only non-Ethernet (L3) packet, but the packets
                     are represented as Ethernet frames for compatibility
                     with legacy OpenFlow controllers that expect this
                     behavior. This requires enabling gpe in options:exts.

              ·      If this option is ptap, Open vSwitch represents packets
                     in the tunnel using the packet_type mechanism
                     introduced in OpenFlow 1.5. This mechanism supports any
                     kind of packet, but actually sending and receiving non-
                     Ethernet packets requires additionally enabling gpe in
                     options:exts.

     Tunnel Options: gre only:

       gre interfaces support these options.

       options : packet_type: optional string, one of legacy_l2, legacy_l3,
       or ptap
              This option controls what types of packets the tunnel sends
              and receives and how it represents them:

              ·      By default, or if this option is legacy_l2, the tunnel
                     sends and receives only Ethernet frames.

              ·      If this option is legacy_l3, the tunnel sends and
                     receives only non-Ethernet (L3) packet, but the packets
                     are represented as Ethernet frames for compatibility
                     with legacy OpenFlow controllers that expect this
                     behavior.

              ·      If this option is ptap, the tunnel sends and receives
                     any kind of packet. Open vSwitch represents packets in
                     the tunnel using the packet_type mechanism introduced
                     in OpenFlow 1.5.

     Tunnel Options: gre, geneve, and vxlan:

       gre, geneve, and vxlan interfaces support these options.

       options : csum: optional string, either true or false
              Optional. Compute encapsulation header (either GRE or UDP)
              checksums on outgoing packets. Default is disabled, set to
              true to enable. Checksums present on incoming packets will be
              validated regardless of this setting.

              When using the upstream Linux kernel module, computation of
              checksums for geneve and vxlan requires Linux kernel version
              4.0 or higher. gre supports checksums for all versions of Open
              vSwitch that support GRE. The out of tree kernel module
              distributed as part of OVS can compute all tunnel checksums on
              any kernel version that it is compatible with.

     Patch Options:

       These options apply only to patch ports, that is, interfaces whose
       type column is patch. Patch ports are mainly a way to connect
       otherwise independent bridges to one another, similar to how one
       might plug an Ethernet cable (a ``patch cable’’) into two physical
       switches to connect those switches. The effect of plugging a patch
       port into two switches is conceptually similar to that of plugging
       the two ends of a Linux veth device into those switches, but the
       implementation of patch ports makes them much more efficient.

       Patch ports may connect two different bridges (the usual case) or the
       same bridge. In the latter case, take special care to avoid loops,
       e.g. by programming appropriate flows with OpenFlow. Patch ports do
       not work if its ends are attached to bridges on different datapaths,
       e.g. to connect bridges in system and netdev datapaths.

       The following command creates and connects patch ports p0 and p1 and
       adds them to bridges br0 and br1, respectively:

       ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \
              -- add-port br1 p1 -- set Interface p1 type=patch options:peer=p0

       options : peer: optional string
              The name of the Interface for the other side of the patch. The
              named Interface’s own peer option must specify this
              Interface’s name. That is, the two patch interfaces must have
              reversed name and peer values.

     PMD (Poll Mode Driver) Options:

       Only PMD netdevs support these options.

       options : n_rxq: optional string, containing an integer, at least 1
              Specifies the maximum number of rx queues to be created for
              PMD netdev. If not specified or specified to 0, one rx queue
              will be created by default. Not supported by DPDK vHost
              interfaces.

       options : dpdk-devargs: optional string
              Specifies the PCI address associated with the port for
              physical devices, or the virtual driver to be used for the
              port when a virtual PMD is intended to be used. For the
              latter, the argument string typically takes the form of
              eth_driver_namex, where driver_name is a valid virtual DPDK
              PMD driver name and x is a unique identifier of your choice
              for the given port. Only supported by the dpdk port type.

       other_config : pmd-rxq-affinity: optional string
              Specifies mapping of RX queues of this interface to CPU cores.

              Value should be set in the following form:

              other_config:pmd-rxq-affinity=<rxq-affinity-list>

              where

              ·      <rxq-affinity-list> ::= NULL | <non-empty-list>

              ·      <non-empty-list> ::= <affinity-pair> | <affinity-pair>
                     , <non-empty-list>

              ·      <affinity-pair> ::= <queue-id> : <core-id>

       options : vhost-server-path: optional string
              The value specifies the path to the socket associated with a
              vHost User client mode device that has been or will be created
              by QEMU. Only supported by dpdkvhostuserclient interfaces.

       options : n_rxq_desc: optional string, containing an integer, in
       range 1 to 4,096
              Specifies the rx queue size (number rx descriptors) for dpdk
              ports. The value must be a power of 2, less than 4096 and
              supported by the hardware of the device being configured. If
              not specified or an incorrect value is specified, 2048 rx
              descriptors will be used by default.

       options : n_txq_desc: optional string, containing an integer, in
       range 1 to 4,096
              Specifies the tx queue size (number tx descriptors) for dpdk
              ports. The value must be a power of 2, less than 4096 and
              supported by the hardware of the device being configured. If
              not specified or an incorrect value is specified, 2048 tx
              descriptors will be used by default.

     MTU:

       The MTU (maximum transmission unit) is the largest amount of data
       that can fit into a single Ethernet frame. The standard Ethernet MTU
       is 1500 bytes. Some physical media and many kinds of virtual
       interfaces can be configured with higher MTUs.

       A client may change an interface MTU by filling in mtu_request. Open
       vSwitch then reports in mtu the currently configured value.

       mtu: optional integer
              The currently configured MTU for the interface.

              This column will be empty for an interface that does not have
              an MTU as, for example, some kinds of tunnels do not.

              Open vSwitch sets this column’s value, so other clients should
              treat it as read-only.

       mtu_request: optional integer, at least 1
              Requested MTU (Maximum Transmission Unit) for the interface. A
              client can fill this column to change the MTU of an interface.

              RFC 791 requires every internet module to be able to forward a
              datagram of 68 octets without further fragmentation. The
              maximum size of an IP packet is 65535 bytes.

              If this is not set and if the interface has internal type,
              Open vSwitch will change the MTU to match the minimum of the
              other interfaces in the bridge.

     Interface Status:

       Status information about interfaces attached to bridges, updated
       every 5 seconds. Not all interfaces have all of these properties;
       virtual interfaces don’t have a link speed, for example. Non-
       applicable columns will have empty values.

       admin_state: optional string, either down or up
              The administrative state of the physical network link.

       link_state: optional string, either down or up
              The observed state of the physical network link. This is
              ordinarily the link’s carrier status. If the interface’s Port
              is a bond configured for miimon monitoring, it is instead the
              network link’s miimon status.

       link_resets: optional integer
              The number of times Open vSwitch has observed the link_state
              of this Interface change.

       link_speed: optional integer
              The negotiated speed of the physical network link. Valid
              values are positive integers greater than 0.

       duplex: optional string, either full or half
              The duplex mode of the physical network link.

       lacp_current: optional boolean
              Boolean value indicating LACP status for this interface. If
              true, this interface has current LACP information about its
              LACP partner. This information may be used to monitor the
              health of interfaces in a LACP enabled port. This column will
              be empty if LACP is not enabled.

       status: map of string-string pairs
              Key-value pairs that report port status. Supported status
              values are type-dependent; some interfaces may not have a
              valid status:driver_name, for example.

       status : driver_name: optional string
              The name of the device driver controlling the network adapter.

       status : driver_version: optional string
              The version string of the device driver controlling the
              network adapter.

       status : firmware_version: optional string
              The version string of the network adapter’s firmware, if
              available.

       status : source_ip: optional string
              The source IP address used for an IPv4/IPv6 tunnel end-point,
              such as gre.

       status : tunnel_egress_iface: optional string
              Egress interface for tunnels. Currently only relevant for
              tunnels on Linux systems, this column will show the name of
              the interface which is responsible for routing traffic
              destined for the configured options:remote_ip. This could be
              an internal interface such as a bridge port.

       status : tunnel_egress_iface_carrier: optional string, either down or
       up
              Whether carrier is detected on status:tunnel_egress_iface.

     Statistics:

       Key-value pairs that report interface statistics. The current
       implementation updates these counters periodically. The update period
       is controlled by other_config:stats-update-interval in the
       Open_vSwitch table. Future implementations may update them when an
       interface is created, when they are queried (e.g. using an OVSDB
       select operation), and just before an interface is deleted due to
       virtual interface hot-unplug or VM shutdown, and perhaps at other
       times, but not on any regular periodic basis.

       These are the same statistics reported by OpenFlow in its struct
       ofp_port_stats structure. If an interface does not support a given
       statistic, then that pair is omitted.

     Statistics: Successful transmit and receive counters:

       statistics : rx_packets: optional integer
              Number of received packets.

       statistics : rx_bytes: optional integer
              Number of received bytes.

       statistics : tx_packets: optional integer
              Number of transmitted packets.

       statistics : tx_bytes: optional integer
              Number of transmitted bytes.

     Statistics: Receive errors:

       statistics : rx_dropped: optional integer
              Number of packets dropped by RX.

       statistics : rx_frame_err: optional integer
              Number of frame alignment errors.

       statistics : rx_over_err: optional integer
              Number of packets with RX overrun.

       statistics : rx_crc_err: optional integer
              Number of CRC errors.

       statistics : rx_errors: optional integer
              Total number of receive errors, greater than or equal to the
              sum of the above.

     Statistics: Transmit errors:

       statistics : tx_dropped: optional integer
              Number of packets dropped by TX.

       statistics : collisions: optional integer
              Number of collisions.

       statistics : tx_errors: optional integer
              Total number of transmit errors, greater than or equal to the
              sum of the above.

     Ingress Policing:

       These settings control ingress policing for packets received on this
       interface. On a physical interface, this limits the rate at which
       traffic is allowed into the system from the outside; on a virtual
       interface (one connected to a virtual machine), this limits the rate
       at which the VM is able to transmit.

       Policing is a simple form of quality-of-service that simply drops
       packets received in excess of the configured rate. Due to its
       simplicity, policing is usually less accurate and less effective than
       egress QoS (which is configured using the QoS and Queue tables).

       Policing is currently implemented on Linux and OVS with DPDK. Both
       implementations use a simple ``token bucket’’ approach:

              ·      The size of the bucket corresponds to
                     ingress_policing_burst. Initially the bucket is full.

              ·      Whenever a packet is received, its size (converted to
                     tokens) is compared to the number of tokens currently
                     in the bucket. If the required number of tokens are
                     available, they are removed and the packet is
                     forwarded. Otherwise, the packet is dropped.

              ·      Whenever it is not full, the bucket is refilled with
                     tokens at the rate specified by ingress_policing_rate.

       Policing interacts badly with some network protocols, and especially
       with fragmented IP packets. Suppose that there is enough network
       activity to keep the bucket nearly empty all the time. Then this
       token bucket algorithm will forward a single packet every so often,
       with the period depending on packet size and on the configured rate.
       All of the fragments of an IP packets are normally transmitted back-
       to-back, as a group. In such a situation, therefore, only one of
       these fragments will be forwarded and the rest will be dropped. IP
       does not provide any way for the intended recipient to ask for only
       the remaining fragments. In such a case there are two likely
       possibilities for what will happen next: either all of the fragments
       will eventually be retransmitted (as TCP will do), in which case the
       same problem will recur, or the sender will not realize that its
       packet has been dropped and data will simply be lost (as some UDP-
       based protocols will do). Either way, it is possible that no forward
       progress will ever occur.

       ingress_policing_rate: integer, at least 0
              Maximum rate for data received on this interface, in kbps.
              Data received faster than this rate is dropped. Set to 0 (the
              default) to disable policing.

       ingress_policing_burst: integer, at least 0
              Maximum burst size for data received on this interface, in kb.
              The default burst size if set to 0 is 8000 kbit. This value
              has no effect if ingress_policing_rate is 0.

              Specifying a larger burst size lets the algorithm be more
              forgiving, which is important for protocols like TCP that
              react severely to dropped packets. The burst size should be at
              least the size of the interface’s MTU. Specifying a value that
              is numerically at least as large as 80% of
              ingress_policing_rate helps TCP come closer to achieving the
              full rate.

     Bidirectional Forwarding Detection (BFD):

       BFD, defined in RFC 5880 and RFC 5881, allows point-to-point
       detection of connectivity failures by occasional transmission of BFD
       control messages. Open vSwitch implements BFD to serve as a more
       popular and standards compliant alternative to CFM.

       BFD operates by regularly transmitting BFD control messages at a rate
       negotiated independently in each direction. Each endpoint specifies
       the rate at which it expects to receive control messages, and the
       rate at which it is willing to transmit them. By default, Open
       vSwitch uses a detection multiplier of three, meaning that an
       endpoint signals a connectivity fault if three consecutive BFD
       control messages fail to arrive. In the case of a unidirectional
       connectivity issue, the system not receiving BFD control messages
       signals the problem to its peer in the messages it transmits.

       The Open vSwitch implementation of BFD aims to comply faithfully with
       RFC 5880 requirements. Open vSwitch does not implement the optional
       Authentication or ``Echo Mode’’ features.

     BFD Configuration:

       A controller sets up key-value pairs in the bfd column to enable and
       configure BFD.

       bfd : enable: optional string, either true or false
              True to enable BFD on this Interface. If not specified, BFD
              will not be enabled by default.

       bfd : min_rx: optional string, containing an integer, at least 1
              The shortest interval, in milliseconds, at which this BFD
              session offers to receive BFD control messages. The remote
              endpoint may choose to send messages at a slower rate.
              Defaults to 1000.

       bfd : min_tx: optional string, containing an integer, at least 1
              The shortest interval, in milliseconds, at which this BFD
              session is willing to transmit BFD control messages. Messages
              will actually be transmitted at a slower rate if the remote
              endpoint is not willing to receive as quickly as specified.
              Defaults to 100.

       bfd : decay_min_rx: optional string, containing an integer
              An alternate receive interval, in milliseconds, that must be
              greater than or equal to bfd:min_rx. The implementation
              switches from bfd:min_rx to bfd:decay_min_rx when there is no
              obvious incoming data traffic at the interface, to reduce the
              CPU and bandwidth cost of monitoring an idle interface. This
              feature may be disabled by setting a value of 0. This feature
              is reset whenever bfd:decay_min_rx or bfd:min_rx changes.

       bfd : forwarding_if_rx: optional string, either true or false
              When true, traffic received on the Interface is used to
              indicate the capability of packet I/O. BFD control packets are
              still transmitted and received. At least one BFD control
              packet must be received every 100 * bfd:min_rx amount of time.
              Otherwise, even if traffic are received, the bfd:forwarding
              will be false.

       bfd : cpath_down: optional string, either true or false
              Set to true to notify the remote endpoint that traffic should
              not be forwarded to this system for some reason other than a
              connectivty failure on the interface being monitored. The
              typical underlying reason is ``concatenated path down,’’ that
              is, that connectivity beyond the local system is down.
              Defaults to false.

       bfd : check_tnl_key: optional string, either true or false
              Set to true to make BFD accept only control messages with a
              tunnel key of zero. By default, BFD accepts control messages
              with any tunnel key.

       bfd : bfd_local_src_mac: optional string
              Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to
              set the MAC used as source for transmitted BFD packets. The
              default is the mac address of the BFD enabled interface.

       bfd : bfd_local_dst_mac: optional string
              Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to
              set the MAC used as destination for transmitted BFD packets.
              The default is 00:23:20:00:00:01.

       bfd : bfd_remote_dst_mac: optional string
              Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to
              set the MAC used for checking the destination of received BFD
              packets. Packets with different destination MAC will not be
              considered as BFD packets. If not specified the destination
              MAC address of received BFD packets are not checked.

       bfd : bfd_src_ip: optional string
              Set to an IPv4 address to set the IP address used as source
              for transmitted BFD packets. The default is 169.254.1.1.

       bfd : bfd_dst_ip: optional string
              Set to an IPv4 address to set the IP address used as
              destination for transmitted BFD packets. The default is
              169.254.1.0.

       bfd : oam: optional string
              Some tunnel protocols (such as Geneve) include a bit in the
              header to indicate that the encapsulated packet is an OAM
              frame. By setting this to true, BFD packets will be marked as
              OAM if encapsulated in one of these tunnels.

       bfd : mult: optional string, containing an integer, in range 1 to 255
              The BFD detection multiplier, which defaults to 3. An endpoint
              signals a connectivity fault if the given number of
              consecutive BFD control messages fail to arrive.

     BFD Status:

       The switch sets key-value pairs in the bfd_status column to report
       the status of BFD on this interface. When BFD is not enabled, with
       bfd:enable, the switch clears all key-value pairs from bfd_status.

       bfd_status : state: optional string, one of admin_down, down, init,
       or up
              Reports the state of the BFD session. The BFD session is fully
              healthy and negotiated if UP.

       bfd_status : forwarding: optional string, either true or false
              Reports whether the BFD session believes this Interface may be
              used to forward traffic. Typically this means the local
              session is signaling UP, and the remote system isn’t signaling
              a problem such as concatenated path down.

       bfd_status : diagnostic: optional string
              A diagnostic code specifying the local system’s reason for the
              last change in session state. The error messages are defined
              in section 4.1 of [RFC 5880].

       bfd_status : remote_state: optional string, one of admin_down, down,
       init, or up
              Reports the state of the remote endpoint’s BFD session.

       bfd_status : remote_diagnostic: optional string
              A diagnostic code specifying the remote system’s reason for
              the last change in session state. The error messages are
              defined in section 4.1 of [RFC 5880].

       bfd_status : flap_count: optional string, containing an integer, at
       least 0
              Counts the number of bfd_status:forwarding flaps since start.
              A flap is considered as a change of the bfd_status:forwarding
              value.

     Connectivity Fault Management:

       802.1ag Connectivity Fault Management (CFM) allows a group of
       Maintenance Points (MPs) called a Maintenance Association (MA) to
       detect connectivity problems with each other. MPs within a MA should
       have complete and exclusive interconnectivity. This is verified by
       occasionally broadcasting Continuity Check Messages (CCMs) at a
       configurable transmission interval.

       According to the 802.1ag specification, each Maintenance Point should
       be configured out-of-band with a list of Remote Maintenance Points it
       should have connectivity to. Open vSwitch differs from the
       specification in this area. It simply assumes the link is faulted if
       no Remote Maintenance Points are reachable, and considers it not
       faulted otherwise.

       When operating over tunnels which have no in_key, or an in_key of
       flow. CFM will only accept CCMs with a tunnel key of zero.

       cfm_mpid: optional integer
              A Maintenance Point ID (MPID) uniquely identifies each
              endpoint within a Maintenance Association. The MPID is used to
              identify this endpoint to other Maintenance Points in the MA.
              Each end of a link being monitored should have a different
              MPID. Must be configured to enable CFM on this Interface.

              According to the 802.1ag specification, MPIDs can only range
              between [1, 8191]. However, extended mode (see
              other_config:cfm_extended) supports eight byte MPIDs.

       cfm_flap_count: optional integer
              Counts the number of cfm fault flapps since boot. A flap is
              considered to be a change of the cfm_fault value.

       cfm_fault: optional boolean
              Indicates a connectivity fault triggered by an inability to
              receive heartbeats from any remote endpoint. When a fault is
              triggered on Interfaces participating in bonds, they will be
              disabled.

              Faults can be triggered for several reasons. Most importantly
              they are triggered when no CCMs are received for a period of
              3.5 times the transmission interval. Faults are also triggered
              when any CCMs indicate that a Remote Maintenance Point is not
              receiving CCMs but able to send them. Finally, a fault is
              triggered if a CCM is received which indicates unexpected
              configuration. Notably, this case arises when a CCM is
              received which advertises the local MPID.

       cfm_fault_status : recv: none
              Indicates a CFM fault was triggered due to a lack of CCMs
              received on the Interface.

       cfm_fault_status : rdi: none
              Indicates a CFM fault was triggered due to the reception of a
              CCM with the RDI bit flagged. Endpoints set the RDI bit in
              their CCMs when they are not receiving CCMs themselves. This
              typically indicates a unidirectional connectivity failure.

       cfm_fault_status : maid: none
              Indicates a CFM fault was triggered due to the reception of a
              CCM with a MAID other than the one Open vSwitch uses. CFM
              broadcasts are tagged with an identification number in
              addition to the MPID called the MAID. Open vSwitch only
              supports receiving CCM broadcasts tagged with the MAID it uses
              internally.

       cfm_fault_status : loopback: none
              Indicates a CFM fault was triggered due to the reception of a
              CCM advertising the same MPID configured in the cfm_mpid
              column of this Interface. This may indicate a loop in the
              network.

       cfm_fault_status : overflow: none
              Indicates a CFM fault was triggered because the CFM module
              received CCMs from more remote endpoints than it can keep
              track of.

       cfm_fault_status : override: none
              Indicates a CFM fault was manually triggered by an
              administrator using an ovs-appctl command.

       cfm_fault_status : interval: none
              Indicates a CFM fault was triggered due to the reception of a
              CCM frame having an invalid interval.

       cfm_remote_opstate: optional string, either down or up
              When in extended mode, indicates the operational state of the
              remote endpoint as either up or down. See
              other_config:cfm_opstate.

       cfm_health: optional integer, in range 0 to 100
              Indicates the health of the interface as a percentage of CCM
              frames received over 21 other_config:cfm_intervals. The health
              of an interface is undefined if it is communicating with more
              than one cfm_remote_mpids. It reduces if healthy heartbeats
              are not received at the expected rate, and gradually improves
              as healthy heartbeats are received at the desired rate. Every
              21 other_config:cfm_intervals, the health of the interface is
              refreshed.

              As mentioned above, the faults can be triggered for several
              reasons. The link health will deteriorate even if heartbeats
              are received but they are reported to be unhealthy. An
              unhealthy heartbeat in this context is a heartbeat for which
              either some fault is set or is out of sequence. The interface
              health can be 100 only on receiving healthy heartbeats at the
              desired rate.

       cfm_remote_mpids: set of integers
              When CFM is properly configured, Open vSwitch will
              occasionally receive CCM broadcasts. These broadcasts contain
              the MPID of the sending Maintenance Point. The list of MPIDs
              from which this Interface is receiving broadcasts from is
              regularly collected and written to this column.

       other_config : cfm_interval: optional string, containing an integer
              The interval, in milliseconds, between transmissions of CFM
              heartbeats. Three missed heartbeat receptions indicate a
              connectivity fault.

              In standard operation only intervals of 3, 10, 100, 1,000,
              10,000, 60,000, or 600,000 ms are supported. Other values will
              be rounded down to the nearest value on the list. Extended
              mode (see other_config:cfm_extended) supports any interval up
              to 65,535 ms. In either mode, the default is 1000 ms.

              We do not recommend using intervals less than 100 ms.

       other_config : cfm_extended: optional string, either true or false
              When true, the CFM module operates in extended mode. This
              causes it to use a nonstandard destination address to avoid
              conflicting with compliant implementations which may be
              running concurrently on the network. Furthermore, extended
              mode increases the accuracy of the cfm_interval configuration
              parameter by breaking wire compatibility with 802.1ag
              compliant implementations. And extended mode allows eight byte
              MPIDs. Defaults to false.

       other_config : cfm_demand: optional string, either true or false
              When true, and other_config:cfm_extended is true, the CFM
              module operates in demand mode. When in demand mode, traffic
              received on the Interface is used to indicate liveness. CCMs
              are still transmitted and received. At least one CCM must be
              received every 100 * other_config:cfm_interval amount of time.
              Otherwise, even if traffic are received, the CFM module will
              raise the connectivity fault.

              Demand mode has a couple of caveats:

              ·      To ensure that ovs-vswitchd has enough time to pull
                     statistics from the datapath, the fault detection
                     interval is set to 3.5 * MAX(other_config:cfm_interval,
                     500) ms.

              ·      To avoid ambiguity, demand mode disables itself when
                     there are multiple remote maintenance points.

              ·      If the Interface is heavily congested, CCMs containing
                     the other_config:cfm_opstate status may be dropped
                     causing changes in the operational state to be delayed.
                     Similarly, if CCMs containing the RDI bit are not
                     received, unidirectional link failures may not be
                     detected.

       other_config : cfm_opstate: optional string, either down or up
              When down, the CFM module marks all CCMs it generates as
              operationally down without triggering a fault. This allows
              remote maintenance points to choose not to forward traffic to
              the Interface on which this CFM module is running. Currently,
              in Open vSwitch, the opdown bit of CCMs affects Interfaces
              participating in bonds, and the bundle OpenFlow action. This
              setting is ignored when CFM is not in extended mode. Defaults
              to up.

       other_config : cfm_ccm_vlan: optional string, containing an integer,
       in range 1 to 4,095
              When set, the CFM module will apply a VLAN tag to all CCMs it
              generates with the given value. May be the string random in
              which case each CCM will be tagged with a different randomly
              generated VLAN.

       other_config : cfm_ccm_pcp: optional string, containing an integer,
       in range 1 to 7
              When set, the CFM module will apply a VLAN tag to all CCMs it
              generates with the given PCP value, the VLAN ID of the tag is
              governed by the value of other_config:cfm_ccm_vlan. If
              other_config:cfm_ccm_vlan is unset, a VLAN ID of zero is used.

     Bonding Configuration:

       other_config : lacp-port-id: optional string, containing an integer,
       in range 1 to 65,535
              The LACP port ID of this Interface. Port IDs are used in LACP
              negotiations to identify individual ports participating in a
              bond.

       other_config : lacp-port-priority: optional string, containing an
       integer, in range 1 to 65,535
              The LACP port priority of this Interface. In LACP negotiations
              Interfaces with numerically lower priorities are preferred for
              aggregation.

       other_config : lacp-aggregation-key: optional string, containing an
       integer, in range 1 to 65,535
              The LACP aggregation key of this Interface. Interfaces with
              different aggregation keys may not be active within a given
              Port at the same time.

     Virtual Machine Identifiers:

       These key-value pairs specifically apply to an interface that
       represents a virtual Ethernet interface connected to a virtual
       machine. These key-value pairs should not be present for other types
       of interfaces. Keys whose names end in -uuid have values that
       uniquely identify the entity in question. For a Citrix XenServer
       hypervisor, these values are UUIDs in RFC 4122 format. Other
       hypervisors may use other formats.

       external_ids : attached-mac: optional string
              The MAC address programmed into the ``virtual hardware’’ for
              this interface, in the form xx:xx:xx:xx:xx:xx. For Citrix
              XenServer, this is the value of the MAC field in the VIF
              record for this interface.

       external_ids : iface-id: optional string
              A system-unique identifier for the interface. On XenServer,
              this will commonly be the same as external_ids:xs-vif-uuid.

       external_ids : iface-status: optional string, either active or
       inactive
              Hypervisors may sometimes have more than one interface
              associated with a given external_ids:iface-id, only one of
              which is actually in use at a given time. For example, in some
              circumstances XenServer has both a ``tap’’ and a ``vif’’
              interface for a single external_ids:iface-id, but only uses
              one of them at a time. A hypervisor that behaves this way must
              mark the currently in use interface active and the others
              inactive. A hypervisor that never has more than one interface
              for a given external_ids:iface-id may mark that interface
              active or omit external_ids:iface-status entirely.

              During VM migration, a given external_ids:iface-id might
              transiently be marked active on two different hypervisors.
              That is, active means that this external_ids:iface-id is the
              active instance within a single hypervisor, not in a broader
              scope. There is one exception: some hypervisors support
              ``migration’’ from a given hypervisor to itself (most often
              for test purposes). During such a ``migration,’’ two instances
              of a single external_ids:iface-id might both be briefly marked
              active on a single hypervisor.

       external_ids : xs-vif-uuid: optional string
              The virtual interface associated with this interface.

       external_ids : xs-network-uuid: optional string
              The virtual network to which this interface is attached.

       external_ids : vm-id: optional string
              The VM to which this interface belongs. On XenServer, this
              will be the same as external_ids:xs-vm-uuid.

       external_ids : xs-vm-uuid: optional string
              The VM to which this interface belongs.

     Auto Attach Configuration:

       Auto Attach configuration for a particular interface.

       lldp : enable: optional string, either true or false
              True to enable LLDP on this Interface. If not specified, LLDP
              will be disabled by default.

     Flow control Configuration:

       Ethernet flow control defined in IEEE 802.1Qbb provides link level
       flow control using MAC pause frames. Implemented only for interfaces
       with type dpdk.

       options : rx-flow-ctrl: optional string, either true or false
              Set to true to enable Rx flow control on physical ports. By
              default, Rx flow control is disabled.

       options : tx-flow-ctrl: optional string, either true or false
              Set to true to enable Tx flow control on physical ports. By
              default, Tx flow control is disabled.

       options : flow-ctrl-autoneg: optional string, either true or false
              Set to true to enable flow control auto negotiation on
              physical ports. By default, auto-neg is disabled.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Flow_Table TABLE         top

       Configuration for a particular OpenFlow table.

   Summary:
       name                          optional string
       Eviction Policy:
         flow_limit                  optional integer, at least 0
         overflow_policy             optional string, either evict or refuse
         groups                      set of strings
       Classifier Optimization:
         prefixes                    set of up to 3 strings
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: optional string
              The table’s name. Set this column to change the name that
              controllers will receive when they request table statistics,
              e.g. ovs-ofctl dump-tables. The name does not affect switch
              behavior.

     Eviction Policy:

       Open vSwitch supports limiting the number of flows that may be
       installed in a flow table, via the flow_limit column. When adding a
       flow would exceed this limit, by default Open vSwitch reports an
       error, but there are two ways to configure Open vSwitch to instead
       delete (``evict’’) a flow to make room for the new one:

              ·      Set the overflow_policy column to evict.

              ·      Send an OpenFlow 1.4+ ``table mod request’’ to enable
                     eviction for the flow table (e.g. ovs-ofctl -O
                     OpenFlow14 mod-table br0 0 evict to enable eviction on
                     flow table 0 of bridge br0).

       When a flow must be evicted due to overflow, the flow to evict is
       chosen through an approximation of the following algorithm. This
       algorithm is used regardless of how eviction was enabled:

              1.
                Divide the flows in the table into groups based on the
                values of the fields or subfields specified in the groups
                column, so that all of the flows in a given group have the
                same values for those fields. If a flow does not specify a
                given field, that field’s value is treated as 0. If groups
                is empty, then all of the flows in the flow table are
                treated as a single group.

              2.
                Consider the flows in the largest group, that is, the group
                that contains the greatest number of flows. If two or more
                groups all have the same largest number of flows, consider
                the flows in all of those groups.

              3.
                If the flows under consideration have different importance
                values, eliminate from consideration any flows except those
                with the lowest importance. (``Importance,’’ a 16-bit
                integer value attached to each flow, was introduced in
                OpenFlow 1.4. Flows inserted with older versions of OpenFlow
                always have an importance of 0.)

              4.
                Among the flows under consideration, choose the flow that
                expires soonest for eviction.

       The eviction process only considers flows that have an idle timeout
       or a hard timeout. That is, eviction never deletes permanent flows.
       (Permanent flows do count against flow_limit.)

       flow_limit: optional integer, at least 0
              If set, limits the number of flows that may be added to the
              table. Open vSwitch may limit the number of flows in a table
              for other reasons, e.g. due to hardware limitations or for
              resource availability or performance reasons.

       overflow_policy: optional string, either evict or refuse
              Controls the switch’s behavior when an OpenFlow flow table
              modification request would add flows in excess of flow_limit.
              The supported values are:

              refuse Refuse to add the flow or flows. This is also the
                     default policy when overflow_policy is unset.

              evict  Delete a flow chosen according to the algorithm
                     described above.

       groups: set of strings
              When overflow_policy is evict, this controls how flows are
              chosen for eviction when the flow table would otherwise exceed
              flow_limit flows. Its value is a set of NXM fields or sub-
              fields, each of which takes one of the forms field[] or
              field[start..end], e.g. NXM_OF_IN_PORT[]. Please see
              meta-flow.h for a complete list of NXM field names.

              Open vSwitch ignores any invalid or unknown field
              specifications.

              When eviction is not enabled, via overflow_policy or an
              OpenFlow 1.4+ ``table mod,’’ this column has no effect.

     Classifier Optimization:

       prefixes: set of up to 3 strings
              This string set specifies which fields should be used for
              address prefix tracking. Prefix tracking allows the classifier
              to skip rules with longer than necessary prefixes, resulting
              in better wildcarding for datapath flows.

              Prefix tracking may be beneficial when a flow table contains
              matches on IP address fields with different prefix lengths.
              For example, when a flow table contains IP address matches on
              both full addresses and proper prefixes, the full address
              matches will typically cause the datapath flow to un-wildcard
              the whole address field (depending on flow entry priorities).
              In this case each packet with a different address gets handed
              to the userspace for flow processing and generates its own
              datapath flow. With prefix tracking enabled for the address
              field in question packets with addresses matching shorter
              prefixes would generate datapath flows where the irrelevant
              address bits are wildcarded, allowing the same datapath flow
              to handle all the packets within the prefix in question. In
              this case many userspace upcalls can be avoided and the
              overall performance can be better.

              This is a performance optimization only, so packets will
              receive the same treatment with or without prefix tracking.

              The supported fields are: tun_id, tun_src, tun_dst,
              tun_ipv6_src, tun_ipv6_dst, nw_src, nw_dst (or aliases ip_src
              and ip_dst), ipv6_src, and ipv6_dst. (Using this feature for
              tun_id would only make sense if the tunnel IDs have prefix
              structure similar to IP addresses.)

              By default, the prefixes=ip_dst,ip_src are used on each flow
              table. This instructs the flow classifier to track the IP
              destination and source addresses used by the rules in this
              specific flow table.

              The keyword none is recognized as an explicit override of the
              default values, causing no prefix fields to be tracked.

              To set the prefix fields, the flow table record needs to
              exist:

              ovs-vsctl set Bridge br0 flow_tables:0=@N1 -- --id=@N1 create
              Flow_Table name=table0
                     Creates a flow table record for the OpenFlow table
                     number 0.

              ovs-vsctl set Flow_Table table0 prefixes=ip_dst,ip_src
                     Enables prefix tracking for IP source and destination
                     address fields.

              There is a maximum number of fields that can be enabled for
              any one flow table. Currently this limit is 3.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

QoS TABLE         top

       Quality of Service (QoS) configuration for each Port that references
       it.

   Summary:
       type                          string
       queues                        map of integer-Queue pairs, key in
                                     range 0 to 4,294,967,295
       Configuration for linux-htb and linux-hfsc:
         other_config : max-rate     optional string, containing an integer
       Configuration for egress-policer QoS:
         other_config : cir          optional string, containing an integer
         other_config : cbs          optional string, containing an integer
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
       type: string
              The type of QoS to implement. The currently defined types are
              listed below:

              linux-htb
                     Linux ``hierarchy token bucket’’ classifier. See tc-
                     htb(8) (also at http://linux.die.net/man/8/tc-htb ) and
                     the HTB manual
                     (http://luxik.cdi.cz/~devik/qos/htb/manual/userg.htm )
                     for information on how this classifier works and how to
                     configure it.

              linux-hfsc
                     Linux "Hierarchical Fair Service Curve" classifier. See
                     http://linux-ip.net/articles/hfsc.en/ for information
                     on how this classifier works.

              linux-sfq
                     Linux ``Stochastic Fairness Queueing’’ classifier. See
                     tc-sfq(8) (also at http://linux.die.net/man/8/tc-sfq )
                     for information on how this classifier works.

              linux-codel
                     Linux ``Controlled Delay’’ classifier. See tc-codel(8)
                     (also at
                     http://man7.org/linux/man-pages/man8/tc-codel.8.html )
                     for information on how this classifier works.

              linux-fq_codel
                     Linux ``Fair Queuing with Controlled Delay’’
                     classifier. See tc-fq_codel(8) (also at
                     http://man7.org/linux/man-pages/man8/tc-fq_codel.8.html )
                     for information on how this classifier works.

              linux-noop
                     Linux ``No operation.’’ By default, Open vSwitch
                     manages quality of service on all of its configured
                     ports. This can be helpful, but sometimes
                     administrators prefer to use other software to manage
                     QoS. This type prevents Open vSwitch from changing the
                     QoS configuration for a port.

              egress-policer
                     A DPDK egress policer algorithm using the DPDK
                     rte_meter library. The rte_meter library provides an
                     implementation which allows the metering and policing
                     of traffic. The implementation in OVS essentially
                     creates a single token bucket used to police traffic.
                     It should be noted that when the rte_meter is
                     configured as part of QoS there will be a performance
                     overhead as the rte_meter itself will consume CPU
                     cycles in order to police traffic. These CPU cycles
                     ordinarily are used for packet proccessing. As such the
                     drop in performance will be noticed in terms of overall
                     aggregate traffic throughput.

       queues: map of integer-Queue pairs, key in range 0 to 4,294,967,295
              A map from queue numbers to Queue records. The supported range
              of queue numbers depend on type. The queue numbers are the
              same as the queue_id used in OpenFlow in struct
              ofp_action_enqueue and other structures.

              Queue 0 is the ``default queue.’’ It is used by OpenFlow
              output actions when no specific queue has been set. When no
              configuration for queue 0 is present, it is automatically
              configured as if a Queue record with empty dscp and
              other_config columns had been specified. (Before version 1.6,
              Open vSwitch would leave queue 0 unconfigured in this case.
              With some queuing disciplines, this dropped all packets
              destined for the default queue.)

     Configuration for linux-htb and linux-hfsc:

       The linux-htb and linux-hfsc classes support the following key-value
       pair:

       other_config : max-rate: optional string, containing an integer
              Maximum rate shared by all queued traffic, in bit/s. Optional.
              If not specified, for physical interfaces, the default is the
              link rate. For other interfaces or if the link rate cannot be
              determined, the default is currently 100 Mbps.

     Configuration for egress-policer QoS:

       QoS type egress-policer provides egress policing for userspace port
       types with DPDK. It has the following key-value pairs defined.

       other_config : cir: optional string, containing an integer
              The Committed Information Rate (CIR) is measured in bytes of
              IP packets per second, i.e. it includes the IP header, but not
              link specific (e.g. Ethernet) headers. This represents the
              bytes per second rate at which the token bucket will be
              updated. The cir value is calculated by (pps x packet data
              size). For example assuming a user wishes to limit a stream
              consisting of 64 byte packets to 1 million packets per second
              the CIR would be set to to to 46000000. This value can be
              broken into ’1,000,000 x 46’. Where 1,000,000 is the policing
              rate for the number of packets per second and 46 represents
              the size of the packet data for a 64 byte ip packet.

       other_config : cbs: optional string, containing an integer
              The Committed Burst Size (CBS) is measured in bytes and
              represents a token bucket. At a minimum this value should be
              be set to the expected largest size packet in the traffic
              stream. In practice larger values may be used to increase the
              size of the token bucket. If a packet can be transmitted then
              the cbs will be decremented by the number of bytes/tokens of
              the packet. If there are not enough tokens in the cbs bucket
              the packet will be dropped.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Queue TABLE         top

       A configuration for a port output queue, used in configuring Quality
       of Service (QoS) features. May be referenced by queues column in QoS
       table.

   Summary:
       dscp                          optional integer, in range 0 to 63
       Configuration for linux-htb QoS:
         other_config : min-rate     optional string, containing an integer,
                                     at least 1
         other_config : max-rate     optional string, containing an integer,
                                     at least 1
         other_config : burst        optional string, containing an integer,
                                     at least 1
         other_config : priority     optional string, containing an integer,
                                     in range 0 to 4,294,967,295
       Configuration for linux-hfsc QoS:
         other_config : min-rate     optional string, containing an integer,
                                     at least 1
         other_config : max-rate     optional string, containing an integer,
                                     at least 1
       Common Columns:
         other_config                map of string-string pairs
         external_ids                map of string-string pairs

   Details:
       dscp: optional integer, in range 0 to 63
              If set, Open vSwitch will mark all traffic egressing this
              Queue with the given DSCP bits. Traffic egressing the default
              Queue is only marked if it was explicitly selected as the
              Queue at the time the packet was output. If unset, the DSCP
              bits of traffic egressing this Queue will remain unchanged.

     Configuration for linux-htb QoS:

       QoS type linux-htb may use queue_ids less than 61440. It has the
       following key-value pairs defined.

       other_config : min-rate: optional string, containing an integer, at
       least 1
              Minimum guaranteed bandwidth, in bit/s.

       other_config : max-rate: optional string, containing an integer, at
       least 1
              Maximum allowed bandwidth, in bit/s. Optional. If specified,
              the queue’s rate will not be allowed to exceed the specified
              value, even if excess bandwidth is available. If unspecified,
              defaults to no limit.

       other_config : burst: optional string, containing an integer, at
       least 1
              Burst size, in bits. This is the maximum amount of ``credits’’
              that a queue can accumulate while it is idle. Optional.
              Details of the linux-htb implementation require a minimum
              burst size, so a too-small burst will be silently ignored.

       other_config : priority: optional string, containing an integer, in
       range 0 to 4,294,967,295
              A queue with a smaller priority will receive all the excess
              bandwidth that it can use before a queue with a larger value
              receives any. Specific priority values are unimportant; only
              relative ordering matters. Defaults to 0 if unspecified.

     Configuration for linux-hfsc QoS:

       QoS type linux-hfsc may use queue_ids less than 61440. It has the
       following key-value pairs defined.

       other_config : min-rate: optional string, containing an integer, at
       least 1
              Minimum guaranteed bandwidth, in bit/s.

       other_config : max-rate: optional string, containing an integer, at
       least 1
              Maximum allowed bandwidth, in bit/s. Optional. If specified,
              the queue’s rate will not be allowed to exceed the specified
              value, even if excess bandwidth is available. If unspecified,
              defaults to no limit.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       other_config: map of string-string pairs

       external_ids: map of string-string pairs

Mirror TABLE         top

       A port mirror within a Bridge.

       A port mirror configures a bridge to send selected frames to special
       ``mirrored’’ ports, in addition to their normal destinations.
       Mirroring traffic may also be referred to as SPAN or RSPAN, depending
       on how the mirrored traffic is sent.

       When a packet enters an Open vSwitch bridge, it becomes eligible for
       mirroring based on its ingress port and VLAN. As the packet travels
       through the flow tables, each time it is output to a port, it becomes
       eligible for mirroring based on the egress port and VLAN. In Open
       vSwitch 2.5 and later, mirroring occurs just after a packet first
       becomes eligible, using the packet as it exists at that point; in
       Open vSwitch 2.4 and earlier, mirroring occurs only after a packet
       has traversed all the flow tables, using the original packet as it
       entered the bridge. This makes a difference only when the flow table
       modifies the packet: in Open vSwitch 2.4, the modifications are never
       visible to mirrors, whereas in Open vSwitch 2.5 and later
       modifications made before the first output that makes it eligible for
       mirroring to a particular destination are visible.

       A packet that enters an Open vSwitch bridge is mirrored to a
       particular destination only once, even if it is eligible for multiple
       reasons. For example, a packet would be mirrored to a particular
       output_port only once, even if it is selected for mirroring to that
       port by select_dst_port and select_src_port in the same or different
       Mirror records.

   Summary:
       name                          string
       Selecting Packets for Mirroring:
         select_all                  boolean
         select_dst_port             set of weak reference to Ports
         select_src_port             set of weak reference to Ports
         select_vlan                 set of up to 4,096 integers, in range 0
                                     to 4,095
       Mirroring Destination Configuration:
         output_port                 optional weak reference to Port
         output_vlan                 optional integer, in range 1 to 4,095
         snaplen                     optional integer, in range 14 to 65,535
       Statistics: Mirror counters:
         statistics : tx_packets     optional integer
         statistics : tx_bytes       optional integer
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string
              Arbitrary identifier for the Mirror.

     Selecting Packets for Mirroring:

       To be selected for mirroring, a given packet must enter or leave the
       bridge through a selected port and it must also be in one of the
       selected VLANs.

       select_all: boolean
              If true, every packet arriving or departing on any port is
              selected for mirroring.

       select_dst_port: set of weak reference to Ports
              Ports on which departing packets are selected for mirroring.

       select_src_port: set of weak reference to Ports
              Ports on which arriving packets are selected for mirroring.

       select_vlan: set of up to 4,096 integers, in range 0 to 4,095
              VLANs on which packets are selected for mirroring. An empty
              set selects packets on all VLANs.

     Mirroring Destination Configuration:

       These columns are mutually exclusive. Exactly one of them must be
       nonempty.

       output_port: optional weak reference to Port
              Output port for selected packets, if nonempty.

              Specifying a port for mirror output reserves that port
              exclusively for mirroring. No frames other than those selected
              for mirroring via this column will be forwarded to the port,
              and any frames received on the port will be discarded.

              The output port may be any kind of port supported by Open
              vSwitch. It may be, for example, a physical port (sometimes
              called SPAN) or a GRE tunnel.

       output_vlan: optional integer, in range 1 to 4,095
              Output VLAN for selected packets, if nonempty.

              The frames will be sent out all ports that trunk output_vlan,
              as well as any ports with implicit VLAN output_vlan. When a
              mirrored frame is sent out a trunk port, the frame’s VLAN tag
              will be set to output_vlan, replacing any existing tag; when
              it is sent out an implicit VLAN port, the frame will not be
              tagged. This type of mirroring is sometimes called RSPAN.

              See the documentation for other_config:forward-bpdu in the
              Interface table for a list of destination MAC addresses which
              will not be mirrored to a VLAN to avoid confusing switches
              that interpret the protocols that they represent.

              Please note: Mirroring to a VLAN can disrupt a network that
              contains unmanaged switches. Consider an unmanaged physical
              switch with two ports: port 1, connected to an end host, and
              port 2, connected to an Open vSwitch configured to mirror
              received packets into VLAN 123 on port 2. Suppose that the end
              host sends a packet on port 1 that the physical switch
              forwards to port 2. The Open vSwitch forwards this packet to
              its destination and then reflects it back on port 2 in VLAN
              123. This reflected packet causes the unmanaged physical
              switch to replace the MAC learning table entry, which
              correctly pointed to port 1, with one that incorrectly points
              to port 2. Afterward, the physical switch will direct packets
              destined for the end host to the Open vSwitch on port 2,
              instead of to the end host on port 1, disrupting connectivity.
              If mirroring to a VLAN is desired in this scenario, then the
              physical switch must be replaced by one that learns Ethernet
              addresses on a per-VLAN basis. In addition, learning should be
              disabled on the VLAN containing mirrored traffic. If this is
              not done then intermediate switches will learn the MAC address
              of each end host from the mirrored traffic. If packets being
              sent to that end host are also mirrored, then they will be
              dropped since the switch will attempt to send them out the
              input port. Disabling learning for the VLAN will cause the
              switch to correctly send the packet out all ports configured
              for that VLAN. If Open vSwitch is being used as an
              intermediate switch, learning can be disabled by adding the
              mirrored VLAN to flood_vlans in the appropriate Bridge table
              or tables.

              Mirroring to a GRE tunnel has fewer caveats than mirroring to
              a VLAN and should generally be preferred.

       snaplen: optional integer, in range 14 to 65,535
              Maximum per-packet number of bytes to mirror.

              A mirrored packet with size larger than snaplen will be
              truncated in datapath to snaplen bytes before sending to the
              mirror output port. If omitted, packets are not truncated.

     Statistics: Mirror counters:

       Key-value pairs that report mirror statistics. The update period is
       controlled by other_config:stats-update-interval in the Open_vSwitch
       table.

       statistics : tx_packets: optional integer
              Number of packets transmitted through this mirror.

       statistics : tx_bytes: optional integer
              Number of bytes transmitted through this mirror.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

Controller TABLE         top

       An OpenFlow controller.

       Open vSwitch supports two kinds of OpenFlow controllers:

              Primary controllers
                     This is the kind of controller envisioned by the
                     OpenFlow 1.0 specification. Usually, a primary
                     controller implements a network policy by taking charge
                     of the switch’s flow table.

                     Open vSwitch initiates and maintains persistent
                     connections to primary controllers, retrying the
                     connection each time it fails or drops. The fail_mode
                     column in the Bridge table applies to primary
                     controllers.

                     Open vSwitch permits a bridge to have any number of
                     primary controllers. When multiple controllers are
                     configured, Open vSwitch connects to all of them
                     simultaneously. Because OpenFlow 1.0 does not specify
                     how multiple controllers coordinate in interacting with
                     a single switch, more than one primary controller
                     should be specified only if the controllers are
                     themselves designed to coordinate with each other. (The
                     Nicira-defined NXT_ROLE OpenFlow vendor extension may
                     be useful for this.)

              Service controllers
                     These kinds of OpenFlow controller connections are
                     intended for occasional support and maintenance use,
                     e.g. with ovs-ofctl. Usually a service controller
                     connects only briefly to inspect or modify some of a
                     switch’s state.

                     Open vSwitch listens for incoming connections from
                     service controllers. The service controllers initiate
                     and, if necessary, maintain the connections from their
                     end. The fail_mode column in the Bridge table does not
                     apply to service controllers.

                     Open vSwitch supports configuring any number of service
                     controllers.

       The target determines the type of controller.

   Summary:
       Core Features:
         target                      string
         connection_mode             optional string, either in-band or
                                     out-of-band
       Controller Failure Detection and Handling:
         max_backoff                 optional integer, at least 1,000
         inactivity_probe            optional integer
       Asynchronous Messages:
         enable_async_messages       optional boolean
         Controller Rate Limiting:
            controller_rate_limit    optional integer, at least 100
            controller_burst_limit   optional integer, at least 25
            Controller Rate Limiting Statistics:
              status : packet-in-TYPE-bypassed
                                     optional string, containing an integer,
                                     at least 0
              status : packet-in-TYPE-queued
                                     optional string, containing an integer,
                                     at least 0
              status : packet-in-TYPE-dropped
                                     optional string, containing an integer,
                                     at least 0
              status : packet-in-TYPE-backlog
                                     optional string, containing an integer,
                                     at least 0
       Additional In-Band Configuration:
         local_ip                    optional string
         local_netmask               optional string
         local_gateway               optional string
       Controller Status:
         is_connected                boolean
         role                        optional string, one of master, other,
                                     or slave
         status : last_error         optional string
         status : state              optional string, one of ACTIVE,
                                     BACKOFF, CONNECTING, IDLE, or VOID
         status : sec_since_connect  optional string, containing an integer,
                                     at least 0
         status : sec_since_disconnect
                                     optional string, containing an integer,
                                     at least 1
       Connection Parameters:
         other_config : dscp         optional string, containing an integer
       Common Columns:
         external_ids                map of string-string pairs
         other_config                map of string-string pairs

   Details:
     Core Features:

       target: string
              Connection method for controller.

              The following connection methods are currently supported for
              primary controllers:

              ssl:ip[:port]
                     The specified SSL port on the host at the given ip,
                     which must be expressed as an IP address (not a DNS
                     name). The ssl column in the Open_vSwitch table must
                     point to a valid SSL configuration when this form is
                     used.

                     If port is not specified, it defaults to 6653.

                     SSL support is an optional feature that is not always
                     built as part of Open vSwitch.

              tcp:ip[:port]
                     The specified TCP port on the host at the given ip,
                     which must be expressed as an IP address (not a DNS
                     name), where ip can be IPv4 or IPv6 address. If ip is
                     an IPv6 address, wrap it in square brackets, e.g.
                     tcp:[::1]:6653.

                     If port is not specified, it defaults to 6653.

              The following connection methods are currently supported for
              service controllers:

              pssl:[port][:ip]
                     Listens for SSL connections on the specified TCP port.
                     If ip, which must be expressed as an IP address (not a
                     DNS name), is specified, then connections are
                     restricted to the specified local IP address (either
                     IPv4 or IPv6). If ip is an IPv6 address, wrap it in
                     square brackets, e.g. pssl:6653:[::1].

                     If port is not specified, it defaults to 6653. If ip is
                     not specified then it listens only on IPv4 (but not
                     IPv6) addresses. The ssl column in the Open_vSwitch
                     table must point to a valid SSL configuration when this
                     form is used.

                     If port is not specified, it currently to 6653.

                     SSL support is an optional feature that is not always
                     built as part of Open vSwitch.

              ptcp:[port][:ip]
                     Listens for connections on the specified TCP port. If
                     ip, which must be expressed as an IP address (not a DNS
                     name), is specified, then connections are restricted to
                     the specified local IP address (either IPv4 or IPv6).
                     If ip is an IPv6 address, wrap it in square brackets,
                     e.g. ptcp:6653:[::1]. If ip is not specified then it
                     listens only on IPv4 addresses.

                     If port is not specified, it defaults to 6653.

              When multiple controllers are configured for a single bridge,
              the target values must be unique. Duplicate target values
              yield unspecified results.

       connection_mode: optional string, either in-band or out-of-band
              If it is specified, this setting must be one of the following
              strings that describes how Open vSwitch contacts this OpenFlow
              controller over the network:

              in-band
                     In this mode, this controller’s OpenFlow traffic
                     travels over the bridge associated with the controller.
                     With this setting, Open vSwitch allows traffic to and
                     from the controller regardless of the contents of the
                     OpenFlow flow table. (Otherwise, Open vSwitch would
                     never be able to connect to the controller, because it
                     did not have a flow to enable it.) This is the most
                     common connection mode because it is not necessary to
                     maintain two independent networks.

              out-of-band
                     In this mode, OpenFlow traffic uses a control network
                     separate from the bridge associated with this
                     controller, that is, the bridge does not use any of its
                     own network devices to communicate with the controller.
                     The control network must be configured separately,
                     before or after ovs-vswitchd is started.

              If not specified, the default is implementation-specific.

     Controller Failure Detection and Handling:

       max_backoff: optional integer, at least 1,000
              Maximum number of milliseconds to wait between connection
              attempts. Default is implementation-specific.

       inactivity_probe: optional integer
              Maximum number of milliseconds of idle time on connection to
              controller before sending an inactivity probe message. If Open
              vSwitch does not communicate with the controller for the
              specified number of seconds, it will send a probe. If a
              response is not received for the same additional amount of
              time, Open vSwitch assumes the connection has been broken and
              attempts to reconnect. Default is implementation-specific. A
              value of 0 disables inactivity probes.

     Asynchronous Messages:

       OpenFlow switches send certain messages to controllers
       spontanenously, that is, not in response to any request from the
       controller. These messages are called ``asynchronous messages.’’
       These columns allow asynchronous messages to be limited or disabled
       to ensure the best use of network resources.

       enable_async_messages: optional boolean
              The OpenFlow protocol enables asynchronous messages at time of
              connection establishment, which means that a controller can
              receive asynchronous messages, potentially many of them, even
              if it turns them off immediately after connecting. Set this
              column to false to change Open vSwitch behavior to disable, by
              default, all asynchronous messages. The controller can use the
              NXT_SET_ASYNC_CONFIG Nicira extension to OpenFlow to turn on
              any messages that it does want to receive, if any.

     Controller Rate Limiting:

       A switch can forward packets to a controller over the OpenFlow
       protocol. Forwarding packets this way at too high a rate can
       overwhelm a controller, frustrate use of the OpenFlow connection for
       other purposes, increase the latency of flow setup, and use an
       unreasonable amount of bandwidth. Therefore, Open vSwitch supports
       limiting the rate of packet forwarding to a controller.

       There are two main reasons in OpenFlow for a packet to be sent to a
       controller: either the packet ``misses’’ in the flow table, that is,
       there is no matching flow, or a flow table action says to send the
       packet to the controller. Open vSwitch limits the rate of each kind
       of packet separately at the configured rate. Therefore, the actual
       rate that packets are sent to the controller can be up to twice the
       configured rate, when packets are sent for both reasons.

       This feature is specific to forwarding packets over an OpenFlow
       connection. It is not general-purpose QoS. See the QoS table for
       quality of service configuration, and ingress_policing_rate in the
       Interface table for ingress policing configuration.

       controller_rate_limit: optional integer, at least 100
              The maximum rate at which the switch will forward packets to
              the OpenFlow controller, in packets per second. If no value is
              specified, rate limiting is disabled.

       controller_burst_limit: optional integer, at least 25
              When a high rate triggers rate-limiting, Open vSwitch queues
              packets to the controller for each port and transmits them to
              the controller at the configured rate. This value limits the
              number of queued packets. Ports on a bridge share the packet
              queue fairly.

              This value has no effect unless controller_rate_limit is
              configured. The current default when this value is not
              specified is one-quarter of controller_rate_limit, meaning
              that queuing can delay forwarding a packet to the controller
              by up to 250 ms.

     Controller Rate Limiting Statistics:

       These values report the effects of rate limiting. Their values are
       relative to establishment of the most recent OpenFlow connection, or
       since rate limiting was enabled, whichever happened more recently.
       Each consists of two values, one with TYPE replaced by miss for rate
       limiting flow table misses, and the other with TYPE replaced by
       action for rate limiting packets sent by OpenFlow actions.

       These statistics are reported only when controller rate limiting is
       enabled.

       status : packet-in-TYPE-bypassed: optional string, containing an
       integer, at least 0
              Number of packets sent directly to the controller, without
              queuing, because the rate did not exceed the configured
              maximum.

       status : packet-in-TYPE-queued: optional string, containing an
       integer, at least 0
              Number of packets added to the queue to send later.

       status : packet-in-TYPE-dropped: optional string, containing an
       integer, at least 0
              Number of packets added to the queue that were later dropped
              due to overflow. This value is less than or equal to
              status:packet-in-TYPE-queued.

       status : packet-in-TYPE-backlog: optional string, containing an
       integer, at least 0
              Number of packets currently queued. The other statistics
              increase monotonically, but this one fluctuates between 0 and
              the controller_burst_limit as conditions change.

     Additional In-Band Configuration:

       These values are considered only in in-band control mode (see
       connection_mode).

       When multiple controllers are configured on a single bridge, there
       should be only one set of unique values in these columns. If
       different values are set for these columns in different controllers,
       the effect is unspecified.

       local_ip: optional string
              The IP address to configure on the local port, e.g.
              192.168.0.123. If this value is unset, then local_netmask and
              local_gateway are ignored.

       local_netmask: optional string
              The IP netmask to configure on the local port, e.g.
              255.255.255.0. If local_ip is set but this value is unset,
              then the default is chosen based on whether the IP address is
              class A, B, or C.

       local_gateway: optional string
              The IP address of the gateway to configure on the local port,
              as a string, e.g. 192.168.0.1. Leave this column unset if this
              network has no gateway.

     Controller Status:

       is_connected: boolean
              true if currently connected to this controller, false
              otherwise.

       role: optional string, one of master, other, or slave
              The level of authority this controller has on the associated
              bridge. Possible values are:

              other  Allows the controller access to all OpenFlow features.

              master Equivalent to other, except that there may be at most
                     one master controller at a time. When a controller
                     configures itself as master, any existing master is
                     demoted to the slave role.

              slave  Allows the controller read-only access to OpenFlow
                     features. Attempts to modify the flow table will be
                     rejected with an error. Slave controllers do not
                     receive OFPT_PACKET_IN or OFPT_FLOW_REMOVED messages,
                     but they do receive OFPT_PORT_STATUS messages.

       status : last_error: optional string
              A human-readable description of the last error on the
              connection to the controller; i.e. strerror(errno). This key
              will exist only if an error has occurred.

       status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING,
       IDLE, or VOID
              The state of the connection to the controller:

              VOID   Connection is disabled.

              BACKOFF
                     Attempting to reconnect at an increasing period.

              CONNECTING
                     Attempting to connect.

              ACTIVE Connected, remote host responsive.

              IDLE   Connection is idle. Waiting for response to keep-alive.

              These values may change in the future. They are provided only
              for human consumption.

       status : sec_since_connect: optional string, containing an integer,
       at least 0
              The amount of time since this controller last successfully
              connected to the switch (in seconds). Value is empty if
              controller has never successfully connected.

       status : sec_since_disconnect: optional string, containing an
       integer, at least 1
              The amount of time since this controller last disconnected
              from the switch (in seconds). Value is empty if controller has
              never disconnected.

     Connection Parameters:

       Additional configuration for a connection between the controller and
       the Open vSwitch.

       other_config : dscp: optional string, containing an integer
              The Differentiated Service Code Point (DSCP) is specified
              using 6 bits in the Type of Service (TOS) field in the IP
              header. DSCP provides a mechanism to classify the network
              traffic and provide Quality of Service (QoS) on IP networks.
              The DSCP value specified here is used when establishing the
              connection between the controller and the Open vSwitch. If no
              value is specified, a default value of 48 is chosen. Valid
              DSCP values must be in the range 0 to 63.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

       other_config: map of string-string pairs

Manager TABLE         top

       Configuration for a database connection to an Open vSwitch database
       (OVSDB) client.

       This table primarily configures the Open vSwitch database
       (ovsdb-server), not the Open vSwitch switch (ovs-vswitchd). The
       switch does read the table to determine what connections should be
       treated as in-band.

       The Open vSwitch database server can initiate and maintain active
       connections to remote clients. It can also listen for database
       connections.

   Summary:
       Core Features:
         target                      string (must be unique within table)
         connection_mode             optional string, either in-band or
                                     out-of-band
       Client Failure Detection and Handling:
         max_backoff                 optional integer, at least 1,000
         inactivity_probe            optional integer
       Status:
         is_connected                boolean
         status : last_error         optional string
         status : state              optional string, one of ACTIVE,
                                     BACKOFF, CONNECTING, IDLE, or VOID
         status : sec_since_connect  optional string, containing an integer,
                                     at least 0
         status : sec_since_disconnect
                                     optional string, containing an integer,
                                     at least 0
         status : locks_held         optional string
         status : locks_waiting      optional string
         status : locks_lost         optional string
         status : n_connections      optional string, containing an integer,
                                     at least 2
         status : bound_port         optional string, containing an integer
       Connection Parameters:
         other_config : dscp         optional string, containing an integer
       Common Columns:
         external_ids                map of string-string pairs
         other_config                map of string-string pairs

   Details:
     Core Features:

       target: string (must be unique within table)
              Connection method for managers.

              The following connection methods are currently supported:

              ssl:ip[:port]
                     The specified SSL port on the host at the given ip,
                     which must be expressed as an IP address (not a DNS
                     name). The ssl column in the Open_vSwitch table must
                     point to a valid SSL configuration when this form is
                     used.

                     If port is not specified, it defaults to 6640.

                     SSL support is an optional feature that is not always
                     built as part of Open vSwitch.

              tcp:ip[:port]
                     The specified TCP port on the host at the given ip,
                     which must be expressed as an IP address (not a DNS
                     name), where ip can be IPv4 or IPv6 address. If ip is
                     an IPv6 address, wrap it in square brackets, e.g.
                     tcp:[::1]:6640.

                     If port is not specified, it defaults to 6640.

              pssl:[port][:ip]
                     Listens for SSL connections on the specified TCP port.
                     Specify 0 for port to have the kernel automatically
                     choose an available port. If ip, which must be
                     expressed as an IP address (not a DNS name), is
                     specified, then connections are restricted to the
                     specified local IP address (either IPv4 or IPv6
                     address). If ip is an IPv6 address, wrap in square
                     brackets, e.g. pssl:6640:[::1]. If ip is not specified
                     then it listens only on IPv4 (but not IPv6) addresses.
                     The ssl column in the Open_vSwitch table must point to
                     a valid SSL configuration when this form is used.

                     If port is not specified, it defaults to 6640.

                     SSL support is an optional feature that is not always
                     built as part of Open vSwitch.

              ptcp:[port][:ip]
                     Listens for connections on the specified TCP port.
                     Specify 0 for port to have the kernel automatically
                     choose an available port. If ip, which must be
                     expressed as an IP address (not a DNS name), is
                     specified, then connections are restricted to the
                     specified local IP address (either IPv4 or IPv6
                     address). If ip is an IPv6 address, wrap it in square
                     brackets, e.g. ptcp:6640:[::1]. If ip is not specified
                     then it listens only on IPv4 addresses.

                     If port is not specified, it defaults to 6640.

              When multiple managers are configured, the target values must
              be unique. Duplicate target values yield unspecified results.

       connection_mode: optional string, either in-band or out-of-band
              If it is specified, this setting must be one of the following
              strings that describes how Open vSwitch contacts this OVSDB
              client over the network:

              in-band
                     In this mode, this connection’s traffic travels over a
                     bridge managed by Open vSwitch. With this setting, Open
                     vSwitch allows traffic to and from the client
                     regardless of the contents of the OpenFlow flow table.
                     (Otherwise, Open vSwitch would never be able to connect
                     to the client, because it did not have a flow to enable
                     it.) This is the most common connection mode because it
                     is not necessary to maintain two independent networks.

              out-of-band
                     In this mode, the client’s traffic uses a control
                     network separate from that managed by Open vSwitch,
                     that is, Open vSwitch does not use any of its own
                     network devices to communicate with the client. The
                     control network must be configured separately, before
                     or after ovs-vswitchd is started.

              If not specified, the default is implementation-specific.

     Client Failure Detection and Handling:

       max_backoff: optional integer, at least 1,000
              Maximum number of milliseconds to wait between connection
              attempts. Default is implementation-specific.

       inactivity_probe: optional integer
              Maximum number of milliseconds of idle time on connection to
              the client before sending an inactivity probe message. If Open
              vSwitch does not communicate with the client for the specified
              number of seconds, it will send a probe. If a response is not
              received for the same additional amount of time, Open vSwitch
              assumes the connection has been broken and attempts to
              reconnect. Default is implementation-specific. A value of 0
              disables inactivity probes.

     Status:

       Key-value pair of is_connected is always updated. Other key-value
       pairs in the status columns may be updated depends on the target
       type.

       When target specifies a connection method that listens for inbound
       connections (e.g. ptcp: or punix:), both n_connections and
       is_connected may also be updated while the remaining key-value pairs
       are omitted.

       On the other hand, when target specifies an outbound connection, all
       key-value pairs may be updated, except the above-mentioned two key-
       value pairs associated with inbound connection targets. They are
       omitted.

       is_connected: boolean
              true if currently connected to this manager, false otherwise.

       status : last_error: optional string
              A human-readable description of the last error on the
              connection to the manager; i.e. strerror(errno). This key will
              exist only if an error has occurred.

       status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING,
       IDLE, or VOID
              The state of the connection to the manager:

              VOID   Connection is disabled.

              BACKOFF
                     Attempting to reconnect at an increasing period.

              CONNECTING
                     Attempting to connect.

              ACTIVE Connected, remote host responsive.

              IDLE   Connection is idle. Waiting for response to keep-alive.

              These values may change in the future. They are provided only
              for human consumption.

       status : sec_since_connect: optional string, containing an integer,
       at least 0
              The amount of time since this manager last successfully
              connected to the database (in seconds). Value is empty if
              manager has never successfully connected.

       status : sec_since_disconnect: optional string, containing an
       integer, at least 0
              The amount of time since this manager last disconnected from
              the database (in seconds). Value is empty if manager has never
              disconnected.

       status : locks_held: optional string
              Space-separated list of the names of OVSDB locks that the
              connection holds. Omitted if the connection does not hold any
              locks.

       status : locks_waiting: optional string
              Space-separated list of the names of OVSDB locks that the
              connection is currently waiting to acquire. Omitted if the
              connection is not waiting for any locks.

       status : locks_lost: optional string
              Space-separated list of the names of OVSDB locks that the
              connection has had stolen by another OVSDB client. Omitted if
              no locks have been stolen from this connection.

       status : n_connections: optional string, containing an integer, at
       least 2
              When target specifies a connection method that listens for
              inbound connections (e.g. ptcp: or pssl:) and more than one
              connection is actually active, the value is the number of
              active connections. Otherwise, this key-value pair is omitted.

       status : bound_port: optional string, containing an integer
              When target is ptcp: or pssl:, this is the TCP port on which
              the OVSDB server is listening. (This is particularly useful
              when target specifies a port of 0, allowing the kernel to
              choose any available port.)

     Connection Parameters:

       Additional configuration for a connection between the manager and the
       Open vSwitch Database.

       other_config : dscp: optional string, containing an integer
              The Differentiated Service Code Point (DSCP) is specified
              using 6 bits in the Type of Service (TOS) field in the IP
              header. DSCP provides a mechanism to classify the network
              traffic and provide Quality of Service (QoS) on IP networks.
              The DSCP value specified here is used when establishing the
              connection between the manager and the Open vSwitch. If no
              value is specified, a default value of 48 is chosen. Valid
              DSCP values must be in the range 0 to 63.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

       other_config: map of string-string pairs

NetFlow TABLE         top

       A NetFlow target. NetFlow is a protocol that exports a number of
       details about terminating IP flows, such as the principals involved
       and duration.

   Summary:
       targets                       set of 1 or more strings
       engine_id                     optional integer, in range 0 to 255
       engine_type                   optional integer, in range 0 to 255
       active_timeout                integer, at least -1
       add_id_to_interface           boolean
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       targets: set of 1 or more strings
              NetFlow targets in the form ip:port. The ip must be specified
              numerically, not as a DNS name.

       engine_id: optional integer, in range 0 to 255
              Engine ID to use in NetFlow messages. Defaults to datapath
              index if not specified.

       engine_type: optional integer, in range 0 to 255
              Engine type to use in NetFlow messages. Defaults to datapath
              index if not specified.

       active_timeout: integer, at least -1
              The interval at which NetFlow records are sent for flows that
              are still active, in seconds. A value of 0 requests the
              default timeout (currently 600 seconds); a value of -1
              disables active timeouts.

              The NetFlow passive timeout, for flows that become inactive,
              is not configurable. It will vary depending on the Open
              vSwitch version, the forms and contents of the OpenFlow flow
              tables, CPU and memory usage, and network activity. A typical
              passive timeout is about a second.

       add_id_to_interface: boolean
              If this column’s value is false, the ingress and egress
              interface fields of NetFlow flow records are derived from
              OpenFlow port numbers. When it is true, the 7 most significant
              bits of these fields will be replaced by the least significant
              7 bits of the engine id. This is useful because many NetFlow
              collectors do not expect multiple switches to be sending
              messages from the same host, so they do not store the engine
              information which could be used to disambiguate the traffic.

              When this option is enabled, a maximum of 508 ports are
              supported.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

SSL TABLE         top

       SSL configuration for an Open_vSwitch.

   Summary:
       private_key                   string
       certificate                   string
       ca_cert                       string
       bootstrap_ca_cert             boolean
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       private_key: string
              Name of a PEM file containing the private key used as the
              switch’s identity for SSL connections to the controller.

       certificate: string
              Name of a PEM file containing a certificate, signed by the
              certificate authority (CA) used by the controller and manager,
              that certifies the switch’s private key, identifying a
              trustworthy switch.

       ca_cert: string
              Name of a PEM file containing the CA certificate used to
              verify that the switch is connected to a trustworthy
              controller.

       bootstrap_ca_cert: boolean
              If set to true, then Open vSwitch will attempt to obtain the
              CA certificate from the controller on its first SSL connection
              and save it to the named PEM file. If it is successful, it
              will immediately drop the connection and reconnect, and from
              then on all SSL connections must be authenticated by a
              certificate signed by the CA certificate thus obtained. This
              option exposes the SSL connection to a man-in-the-middle
              attack obtaining the initial CA certificate. It may still be
              useful for bootstrapping.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

sFlow TABLE         top

       A set of sFlow(R) targets. sFlow is a protocol for remote monitoring
       of switches.

   Summary:
       agent                         optional string
       header                        optional integer
       polling                       optional integer
       sampling                      optional integer
       targets                       set of 1 or more strings
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       agent: optional string
              Name of the network device whose IP address should be reported
              as the ``agent address’’ to collectors. If not specified, the
              agent device is figured from the first target address and the
              routing table. If the routing table does not contain a route
              to the target, the IP address defaults to the local_ip in the
              collector’s Controller. If an agent IP address cannot be
              determined any of these ways, sFlow is disabled.

       header: optional integer
              Number of bytes of a sampled packet to send to the collector.
              If not specified, the default is 128 bytes.

       polling: optional integer
              Polling rate in seconds to send port statistics to the
              collector. If not specified, defaults to 30 seconds.

       sampling: optional integer
              Rate at which packets should be sampled and sent to the
              collector. If not specified, defaults to 400, which means one
              out of 400 packets, on average, will be sent to the collector.

       targets: set of 1 or more strings
              sFlow targets in the form ip:port.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

IPFIX TABLE         top

       Configuration for sending packets to IPFIX collectors.

       IPFIX is a protocol that exports a number of details about flows. The
       IPFIX implementation in Open vSwitch samples packets at a
       configurable rate, extracts flow information from those packets,
       optionally caches and aggregates the flow information, and sends the
       result to one or more collectors.

       IPFIX in Open vSwitch can be configured two different ways:

              ·      With per-bridge sampling, Open vSwitch performs IPFIX
                     sampling automatically on all packets that pass through
                     a bridge. To configure per-bridge sampling, create an
                     IPFIX record and point a Bridge table’s ipfix column to
                     it. The Flow_Sample_Collector_Set table is not used for
                     per-bridge sampling.

              ·      With flow-based sampling, sample actions in the
                     OpenFlow flow table drive IPFIX sampling. See
                     ovs-ofctl(8) for a description of the sample action.

                     Flow-based sampling also requires database
                     configuration: create a IPFIX record that describes the
                     IPFIX configuration and a Flow_Sample_Collector_Set
                     record that points to the Bridge whose flow table holds
                     the sample actions and to IPFIX record. The ipfix in
                     the Bridge table is not used for flow-based sampling.

   Summary:
       targets                       set of strings
       cache_active_timeout          optional integer, in range 0 to 4,200
       cache_max_flows               optional integer, in range 0 to
                                     4,294,967,295
       other_config : enable-tunnel-sampling
                                     optional string, either true or false
       other_config : virtual_obs_id optional string
       Per-Bridge Sampling:
         sampling                    optional integer, in range 1 to
                                     4,294,967,295
         obs_domain_id               optional integer, in range 0 to
                                     4,294,967,295
         obs_point_id                optional integer, in range 0 to
                                     4,294,967,295
         other_config : enable-input-sampling
                                     optional string, either true or false
         other_config : enable-output-sampling
                                     optional string, either true or false
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       targets: set of strings
              IPFIX target collectors in the form ip:port.

       cache_active_timeout: optional integer, in range 0 to 4,200
              The maximum period in seconds for which an IPFIX flow record
              is cached and aggregated before being sent. If not specified,
              defaults to 0. If 0, caching is disabled.

       cache_max_flows: optional integer, in range 0 to 4,294,967,295
              The maximum number of IPFIX flow records that can be cached at
              a time. If not specified, defaults to 0. If 0, caching is
              disabled.

       other_config : enable-tunnel-sampling: optional string, either true
       or false
              Set to true to enable sampling and reporting tunnel header
              7-tuples in IPFIX flow records. Tunnel sampling is enabled by
              default.

              The following enterprise entities report the sampled tunnel
              info:

              tunnelType:
                     ID: 891, and enterprise ID 6876 (VMware).

                     type: unsigned 8-bit integer.

                     data type semantics: identifier.

                     description: Identifier of the layer 2 network overlay
                     network encapsulation type: 0x01 VxLAN, 0x02 GRE, 0x03
                     LISP, 0x07 GENEVE.

              tunnelKey:
                     ID: 892, and enterprise ID 6876 (VMware).

                     type: variable-length octetarray.

                     data type semantics: identifier.

                     description: Key which is used for identifying an
                     individual traffic flow within a VxLAN (24-bit VNI),
                     GENEVE (24-bit VNI), GRE (32-bit key), or LISP (24-bit
                     instance ID) tunnel. The key is encoded in this
                     octetarray as a 3-, 4-, or 8-byte integer ID in network
                     byte order.

              tunnelSourceIPv4Address:
                     ID: 893, and enterprise ID 6876 (VMware).

                     type: unsigned 32-bit integer.

                     data type semantics: identifier.

                     description: The IPv4 source address in the tunnel IP
                     packet header.

              tunnelDestinationIPv4Address:
                     ID: 894, and enterprise ID 6876 (VMware).

                     type: unsigned 32-bit integer.

                     data type semantics: identifier.

                     description: The IPv4 destination address in the tunnel
                     IP packet header.

              tunnelProtocolIdentifier:
                     ID: 895, and enterprise ID 6876 (VMware).

                     type: unsigned 8-bit integer.

                     data type semantics: identifier.

                     description: The value of the protocol number in the
                     tunnel IP packet header. The protocol number identifies
                     the tunnel IP packet payload type.

              tunnelSourceTransportPort:
                     ID: 896, and enterprise ID 6876 (VMware).

                     type: unsigned 16-bit integer.

                     data type semantics: identifier.

                     description: The source port identifier in the tunnel
                     transport header. For the transport protocols UDP, TCP,
                     and SCTP, this is the source port number given in the
                     respective header.

              tunnelDestinationTransportPort:
                     ID: 897, and enterprise ID 6876 (VMware).

                     type: unsigned 16-bit integer.

                     data type semantics: identifier.

                     description: The destination port identifier in the
                     tunnel transport header. For the transport protocols
                     UDP, TCP, and SCTP, this is the destination port number
                     given in the respective header.

              Before Open vSwitch 2.5.90, other_config:enable-tunnel-
              sampling was only supported with per-bridge sampling, and
              ignored otherwise. Open vSwitch 2.5.90 and later support
              other_config:enable-tunnel-sampling for per-bridge and per-
              flow sampling.

       other_config : virtual_obs_id: optional string
              A string that accompanies each IPFIX flow record. Its intended
              use is for the ``virtual observation ID,’’ an identifier of a
              virtual observation point that is locally unique in a virtual
              network. It describes a location in the virtual network where
              IP packets can be observed. The maximum length is 254 bytes.
              If not specified, the field is omitted from the IPFIX flow
              record.

              The following enterprise entity reports the specified virtual
              observation ID:

              virtualObsID:
                     ID: 898, and enterprise ID 6876 (VMware).

                     type: variable-length string.

                     data type semantics: identifier.

                     description: A virtual observation domain ID that is
                     locally unique in a virtual network.

              This feature was introduced in Open vSwitch 2.5.90.

     Per-Bridge Sampling:

       These values affect only per-bridge sampling. See above for a
       description of the differences between per-bridge and flow-based
       sampling.

       sampling: optional integer, in range 1 to 4,294,967,295
              The rate at which packets should be sampled and sent to each
              target collector. If not specified, defaults to 400, which
              means one out of 400 packets, on average, will be sent to each
              target collector.

       obs_domain_id: optional integer, in range 0 to 4,294,967,295
              The IPFIX Observation Domain ID sent in each IPFIX packet. If
              not specified, defaults to 0.

       obs_point_id: optional integer, in range 0 to 4,294,967,295
              The IPFIX Observation Point ID sent in each IPFIX flow record.
              If not specified, defaults to 0.

       other_config : enable-input-sampling: optional string, either true or
       false
              By default, Open vSwitch samples and reports flows at bridge
              port input in IPFIX flow records. Set this column to false to
              disable input sampling.

       other_config : enable-output-sampling: optional string, either true
       or false
              By default, Open vSwitch samples and reports flows at bridge
              port output in IPFIX flow records. Set this column to false to
              disable output sampling.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

Flow_Sample_Collector_Set TABLE         top

       A set of IPFIX collectors of packet samples generated by OpenFlow
       sample actions. This table is used only for IPFIX flow-based
       sampling, not for per-bridge sampling (see the IPFIX table for a
       description of the two forms).

   Summary:
       id                            integer, in range 0 to 4,294,967,295
       bridge                        Bridge
       ipfix                         optional IPFIX
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       id: integer, in range 0 to 4,294,967,295
              The ID of this collector set, unique among the bridge’s
              collector sets, to be used as the collector_set_id in OpenFlow
              sample actions.

       bridge: Bridge
              The bridge into which OpenFlow sample actions can be added to
              send packet samples to this set of IPFIX collectors.

       ipfix: optional IPFIX
              Configuration of the set of IPFIX collectors to send one flow
              record per sampled packet to.

     Common Columns:

       The overall purpose of these columns is described under Common
       Columns at the beginning of this document.

       external_ids: map of string-string pairs

AutoAttach TABLE         top

       Auto Attach configuration within a bridge. The IETF Auto-Attach SPBM
       draft standard describes a compact method of using IEEE 802.1AB Link
       Layer Discovery Protocol (LLDP) together with a IEEE 802.1aq Shortest
       Path Bridging (SPB) network to automatically attach network devices
       to individual services in a SPB network. The intent here is to allow
       network applications and devices using OVS to be able to easily take
       advantage of features offered by industry standard SPB networks.

       Auto Attach (AA) uses LLDP to communicate between a directly
       connected Auto Attach Client (AAC) and Auto Attach Server (AAS). The
       LLDP protocol is extended to add two new Type-Length-Value tuples
       (TLVs). The first new TLV supports the ongoing discovery of directly
       connected AA correspondents. Auto Attach operates by regularly
       transmitting AA discovery TLVs between the AA client and AA server.
       By exchanging these discovery messages, both the AAC and AAS learn
       the system name and system description of their peer. In the OVS
       context, OVS operates as the AA client and the AA server resides on a
       switch at the edge of the SPB network.

       Once AA discovery has been completed the AAC then uses the second new
       TLV to deliver identifier mappings from the AAC to the AAS. A primary
       feature of Auto Attach is to facilitate the mapping of VLANs defined
       outside the SPB network onto service ids (ISIDs) defined within the
       SPM network. By doing so individual external VLANs can be mapped onto
       specific SPB network services. These VLAN id to ISID mappings can be
       configured and managed locally using new options added to the ovs-
       vsctl command.

       The Auto Attach OVS feature does not provide a full implementation of
       the LLDP protocol. Support for the mandatory TLVs as defined by the
       LLDP standard and support for the AA TLV extensions is provided. LLDP
       protocol support in OVS can be enabled or disabled on a port by port
       basis. LLDP support is disabled by default.

   Summary:
       system_name                   string
       system_description            string
       mappings                      map of integer-integer pairs, key in
                                     range 0 to 16,777,215, value in range 0
                                     to 4,095

   Details:
       system_name: string
              The system_name string is exported in LLDP messages. It should
              uniquely identify the bridge in the network.

       system_description: string
              The system_description string is exported in LLDP messages. It
              should describe the type of software and hardware.

       mappings: map of integer-integer pairs, key in range 0 to 16,777,215,
       value in range 0 to 4,095
              A mapping from SPB network Individual Service Identifier
              (ISID) to VLAN id.

COLOPHON         top

       This page is part of the Open vSwitch (a distributed virtual
       multilayer switch) project.  Information about the project can be
       found at ⟨http://openvswitch.org/⟩.  If you have a bug report for
       this manual page, send it to bugs@openvswitch.org.  This page was
       obtained from the project's upstream Git repository
       ⟨https://github.com/openvswitch/ovs.git⟩ on 2018-02-02.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2018-02-01.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to man-pages@man7.org

Open vSwitch 2.8.90            DB Schema 7.15.1      ovs-vswitchd.conf.db(5)

Pages that refer to this page: ovsdb-client(1)ovsdb-tool(1)ovn-architecture(7)ovs-fields(7)ovn-controller(8)ovs-dpctl(8)ovs-ofctl(8)ovs-vsctl(8)ovs-vswitchd(8)