ovs-ofctl(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | RUNTIME MANAGEMENT COMMANDS | EXAMPLES | SEE ALSO | COLOPHON

ovs-ofctl(8)               Open vSwitch Manual              ovs-ofctl(8)

NAME         top

       ovs-ofctl - administer OpenFlow switches

SYNOPSIS         top

       ovs-ofctl [options] command [switch] [args...]

DESCRIPTION         top

       The ovs-ofctl program is a command line tool for monitoring and
       administering OpenFlow switches.  It can also show the current
       state of an OpenFlow switch, including features, configuration,
       and table entries.  It should work with any OpenFlow switch, not
       just Open vSwitch.

   OpenFlow Switch Management Commands
       These commands allow ovs-ofctl to monitor and administer an
       OpenFlow switch.  It is able to show the current state of a
       switch, including features, configuration, and table entries.

       Most of these commands take an argument that specifies the method
       for connecting to an OpenFlow switch.  The following connection
       methods are supported:

              ssl:host[:port]
              tcp:host[:port]
                     The specified port on the given host, which can be
                     expressed either as a DNS name (if built with
                     unbound library) or an IP address in IPv4 or IPv6
                     address format.  Wrap IPv6 addresses in square
                     brackets, e.g. tcp:[::1]:6653.  On Linux, use
                     %device to designate a scope for IPv6 link-level
                     addresses, e.g. tcp:[fe80::1234%eth0]:6653.  For
                     ssl, the --private-key, --certificate, and
                     --ca-cert options are mandatory.

                     If port is not specified, it defaults to 6653.

              unix:file
                     On POSIX, a Unix domain server socket named file.

                     On Windows, connect to a local named pipe that is
                     represented by a file created in the path file to
                     mimic the behavior of a Unix domain socket.

              file   This is short for unix:file, as long as file does
                     not contain a colon.

              bridge This is short for
                     unix:/usr/local/var/run/openvswitch/bridge.mgmt, as
                     long as bridge does not contain a colon.

              [type@]dp
                     Attempts to look up the bridge associated with dp
                     and open as above.  If type is given, it specifies
                     the datapath provider of dp, otherwise the default
                     provider system is assumed.

       show switch
              Prints to the console information on switch, including
              information on its flow tables and ports.

       dump-tables switch
              Prints to the console statistics for each of the flow
              tables used by switch.

       dump-table-features switch
              Prints to the console features for each of the flow tables
              used by switch.

       dump-table-desc switch
              Prints to the console configuration for each of the flow
              tables used by switch for OpenFlow 1.4+.

       mod-table switch table setting
              This command configures flow table settings in switch for
              OpenFlow table table, which may be expressed as a number
              or (unless --no-names is specified) a name.

              The available settings depend on the OpenFlow version in
              use.  In OpenFlow 1.1 and 1.2 (which must be enabled with
              the -O option) only, mod-table configures behavior when no
              flow is found when a packet is looked up in a flow table.
              The following setting values are available:

              drop   Drop the packet.

              continue
                     Continue to the next table in the pipeline.  (This
                     is how an OpenFlow 1.0 switch always handles
                     packets that do not match any flow, in tables other
                     than the last one.)

              controller
                     Send to controller.  (This is how an OpenFlow 1.0
                     switch always handles packets that do not match any
                     flow in the last table.)

              In OpenFlow 1.3 and later (which must be enabled with the
              -O option) and Open vSwitch 2.11 and later only, mod-table
              can change the name of a table:

              name:new-name
                     Changes the name of the table to new-name.  Use an
                     empty new-name to clear the name.  (This will be
                     ineffective if the name is set via the name column
                     in the Flow_Table table in the Open_vSwitch
                     database as described in ovs-vswitchd.conf.db(5).)

              In OpenFlow 1.4 and later (which must be enabled with the
              -O option) only, mod-table configures the behavior when a
              controller attempts to add a flow to a flow table that is
              full.  The following setting values are available:

              evict  Delete some existing flow from the flow table,
                     according to the algorithm described for the
                     Flow_Table table in ovs-vswitchd.conf.db(5).

              noevict
                     Refuse to add the new flow.  (Eviction might still
                     be enabled through the overflow_policy column in
                     the Flow_Table table documented in
                     ovs-vswitchd.conf.db(5).)

              vacancy:low,high
                     Enables sending vacancy events to controllers using
                     TABLE_STATUS messages, based on percentage
                     thresholds low and high.

              novacancy
                     Disables vacancy events.

       dump-ports switch [netdev]
              Prints to the console statistics for network devices
              associated with switch.  If netdev is specified, only the
              statistics associated with that device will be printed.
              netdev can be an OpenFlow assigned port number or device
              name, e.g. eth0.

       dump-ports-desc switch [port]
              Prints to the console detailed information about network
              devices associated with switch.  To dump only a specific
              port, specify its number as port.  Otherwise, if port is
              omitted, or if it is specified as ANY, then all ports are
              printed.  This is a subset of the information provided by
              the show command.

              If the connection to switch negotiates OpenFlow 1.0, 1.2,
              or 1.2, this command uses an OpenFlow extension only
              implemented in Open vSwitch (version 1.7 and later).

              Only OpenFlow 1.5 and later support dumping a specific
              port.  Earlier versions of OpenFlow always dump all ports.

       mod-port switch port action
              Modify characteristics of port port in switch.  port may
              be an OpenFlow port number or name (unless --no-names is
              specified) or the keyword LOCAL (the preferred way to
              refer to the OpenFlow local port).  The action may be any
              one of the following:
              up
              down   Enable or disable the interface.  This is
                     equivalent to ip link set up or ip link set down on
                     a Unix system.

              stp
              no-stp Enable or disable 802.1D spanning tree protocol
                     (STP) on the interface.  OpenFlow implementations
                     that don't support STP will refuse to enable it.

              receive
              no-receive
              receive-stp
              no-receive-stp
                     Enable or disable OpenFlow processing of packets
                     received on this interface.  When packet processing
                     is disabled, packets will be dropped instead of
                     being processed through the OpenFlow table.  The
                     receive or no-receive setting applies to all
                     packets except 802.1D spanning tree packets, which
                     are separately controlled by receive-stp or
                     no-receive-stp.

              forward
              no-forward
                     Allow or disallow forwarding of traffic to this
                     interface.  By default, forwarding is enabled.

              flood
              no-flood
                     Controls whether an OpenFlow flood action will send
                     traffic out this interface.  By default, flooding
                     is enabled.  Disabling flooding is primarily useful
                     to prevent loops when a spanning tree protocol is
                     not in use.

              packet-in
              no-packet-in
                     Controls whether packets received on this interface
                     that do not match a flow table entry generate a
                     ``packet in'' message to the OpenFlow controller.
                     By default, ``packet in'' messages are enabled.

              The show command displays (among other information) the
              configuration that mod-port changes.

       get-frags switch
              Prints switch's fragment handling mode.  See set-frags,
              below, for a description of each fragment handling mode.

              The show command also prints the fragment handling mode
              among its other output.

       set-frags switch frag_mode
              Configures switch's treatment of IPv4 and IPv6 fragments.
              The choices for frag_mode are:

              normal Fragments pass through the flow table like non-
                     fragmented packets.  The TCP ports, UDP ports, and
                     ICMP type and code fields are always set to 0, even
                     for fragments where that information would
                     otherwise be available (fragments with offset 0).
                     This is the default fragment handling mode for an
                     OpenFlow switch.

              drop   Fragments are dropped without passing through the
                     flow table.

              reassemble
                     The switch reassembles fragments into full IP
                     packets before passing them through the flow table.
                     Open vSwitch does not implement this fragment
                     handling mode.

              nx-match
                     Fragments pass through the flow table like non-
                     fragmented packets.  The TCP ports, UDP ports, and
                     ICMP type and code fields are available for
                     matching for fragments with offset 0, and set to 0
                     in fragments with nonzero offset.  This mode is a
                     Nicira extension.

              See the description of ip_frag, in ovs-fields(7), for a
              way to match on whether a packet is a fragment and on its
              fragment offset.

       dump-flows switch [flows]
              Prints to the console all flow entries in switch's tables
              that match flows.  If flows is omitted, all flows in the
              switch are retrieved.  See Flow Syntax, below, for the
              syntax of flows.  The output format is described in Table
              Entry Output.

              By default, ovs-ofctl prints flow entries in the same
              order that the switch sends them, which is unlikely to be
              intuitive or consistent.  Use --sort and --rsort to
              control display order.  The --names/--no-names and
              --stats/--no-stats options also affect output formatting.
              See the descriptions of these options, under OPTIONS
              below, for more information

       dump-aggregate switch [flows]
              Prints to the console aggregate statistics for flows in
              switch's tables that match flows.  If flows is omitted,
              the statistics are aggregated across all flows in the
              switch's flow tables.  See Flow Syntax, below, for the
              syntax of flows.  The output format is described in Table
              Entry Output.

       queue-stats switch [port [queue]]
              Prints to the console statistics for the specified queue
              on port within switch.  port can be an OpenFlow port
              number or name, the keyword LOCAL (the preferred way to
              refer to the OpenFlow local port), or the keyword ALL.
              Either of port or queue or both may be omitted (or
              equivalently the keyword ALL).  If both are omitted,
              statistics are printed for all queues on all ports.  If
              only queue is omitted, then statistics are printed for all
              queues on port; if only port is omitted, then statistics
              are printed for queue on every port where it exists.

       queue-get-config switch [port [queue]]
              Prints to the console the configuration of queue on port
              in switch.  If port is omitted or ANY, reports queues for
              all port.  If queue is omitted or ANY, reports all queues.
              For OpenFlow 1.3 and earlier, the output always includes
              all queues, ignoring queue if specified.

              This command has limited usefulness, because ports often
              have no configured queues and because the OpenFlow
              protocol provides only very limited information about the
              configuration of a queue.

       dump-ipfix-bridge switch
              Prints to the console the statistics of bridge IPFIX for
              switch.  If bridge IPFIX is configured on the switch,
              IPFIX statistics can be retrieved.  Otherwise, error
              message will be printed.

              This command uses an Open vSwitch extension that is only
              in Open vSwitch 2.6 and later.

       dump-ipfix-flow switch
              Prints to the console the statistics of flow-based IPFIX
              for switch.  If flow-based IPFIX is configured on the
              switch, statistics of all the collector set ids on the
              switch will be printed.  Otherwise, print error message.

              Refer to ovs-vswitchd.conf.db(5) for more details on
              configuring flow based IPFIX and collector set ids.

              This command uses an Open vSwitch extension that is only
              in Open vSwitch 2.6 and later.

       ct-flush-zone switch zone
              Flushes the connection tracking entries in zone on switch.

              This command uses an Open vSwitch extension that is only
              in Open vSwitch 2.6 and later.

   OpenFlow Switch Flow Table Commands
       These commands manage the flow table in an OpenFlow switch.  In
       each case, flow specifies a flow entry in the format described in
       Flow Syntax, below, file is a text file that contains zero or
       more flows in the same syntax, one per line, and the optional
       --bundle option operates the command as a single atomic
       transation, see option --bundle, below.

       [--bundle] add-flow switch flow
       [--bundle] add-flow switch - < file
       [--bundle] add-flows switch file
              Add each flow entry to switch's tables.  Each flow
              specification (e.g., each line in file) may start with
              add, modify, delete, modify_strict, or delete_strict
              keyword to specify whether a flow is to be added,
              modified, or deleted, and whether the modify or delete is
              strict or not.  For backwards compatibility a flow
              specification without one of these keywords is treated as
              a flow add.  All flow mods are executed in the order
              specified.

       [--bundle] [--strict] mod-flows switch flow
       [--bundle] [--strict] mod-flows switch - < file
              Modify the actions in entries from switch's tables that
              match the specified flows.  With --strict, wildcards are
              not treated as active for matching purposes.

       [--bundle] del-flows switch
       [--bundle] [--strict] del-flows switch [flow]
       [--bundle] [--strict] del-flows switch - < file
              Deletes entries from switch's flow table.  With only a
              switch argument, deletes all flows.  Otherwise, deletes
              flow entries that match the specified flows.  With
              --strict, wildcards are not treated as active for matching
              purposes.

       [--bundle] [--readd] replace-flows switch file
              Reads flow entries from file (or stdin if file is -) and
              queries the flow table from switch.  Then it fixes up any
              differences, adding flows from flow that are missing on
              switch, deleting flows from switch that are not in file,
              and updating flows in switch whose actions, cookie, or
              timeouts differ in file.

              With --readd, ovs-ofctl adds all the flows from file, even
              those that exist with the same actions, cookie, and
              timeout in switch.  In OpenFlow 1.0 and 1.1, re-adding a
              flow always resets the flow's packet and byte counters to
              0, and in OpenFlow 1.2 and later, it does so only if the
              reset_counts flag is set.

       diff-flows source1 source2
              Reads flow entries from source1 and source2 and prints the
              differences.  A flow that is in source1 but not in source2
              is printed preceded by a -, and a flow that is in source2
              but not in source1 is printed preceded by a +.  If a flow
              exists in both source1 and source2 with different actions,
              cookie, or timeouts, then both versions are printed
              preceded by - and +, respectively.

              source1 and source2 may each name a file or a switch.  If
              a name begins with / or ., then it is considered to be a
              file name.  A name that contains : is considered to be a
              switch.  Otherwise, it is a file if a file by that name
              exists, a switch if not.

              For this command, an exit status of 0 means that no
              differences were found, 1 means that an error occurred,
              and 2 means that some differences were found.

       packet-out switch packet-out
              Connects to switch and instructs it to execute the packet-
              out OpenFlow message, specified as defined in Packet-Out
              Syntax section.

   Group Table Commands
       These commands manage the group table in an OpenFlow switch.  In
       each case, group specifies a group entry in the format described
       in Group Syntax, below, and file is a text file that contains
       zero or more groups in the same syntax, one per line, and the
       optional --bundle option operates the command as a single atomic
       transation, see option --bundle, below.

       The group commands work only with switches that support OpenFlow
       1.1 or later or the Open vSwitch group extensions to OpenFlow 1.0
       (added in Open vSwitch 2.9.90).  For OpenFlow 1.1 or later, it is
       necessary to explicitly enable these protocol versions in
       ovs-ofctl (using -O).  For more information, see ``Q: What
       versions of OpenFlow does Open vSwitch support?'' in the Open
       vSwitch FAQ.

       [--bundle] add-group switch group
       [--bundle] add-group switch - < file
       [--bundle] add-groups switch file
              Add each group entry to switch's tables.  Each group
              specification (e.g., each line in file) may start with
              add, modify, add_or_mod, delete, insert_bucket, or
              remove_bucket keyword to specify whether a flow is to be
              added, modified, or deleted, or whether a group bucket is
              to be added or removed.  For backwards compatibility a
              group specification without one of these keywords is
              treated as a group add.  All group mods are executed in
              the order specified.

       [--bundle] [--may-create] mod-group switch group
       [--bundle] [--may-create] mod-group switch - < file
              Modify the action buckets in entries from switch's tables
              for each group entry.  If a specified group does not
              already exist, then without --may-create, this command has
              no effect; with --may-create, it creates a new group.  The
              --may-create option uses an Open vSwitch extension to
              OpenFlow only implemented in Open vSwitch 2.6 and later.

       [--bundle] del-groups switch
       [--bundle] del-groups switch [group]
       [--bundle] del-groups switch - < file
              Deletes entries from switch's group table.  With only a
              switch argument, deletes all groups.  Otherwise, deletes
              the group for each group entry.

       [--bundle] insert-buckets switch group
       [--bundle] insert-buckets switch - < file
              Add buckets to an existing group present in the switch's
              group table.  If no command_bucket_id is present in the
              group specification then all buckets of the group are
              removed.

       [--bundle] remove-buckets switch group
       [--bundle] remove-buckets switch - < file
              Remove buckets to an existing group present in the
              switch's group table.  If no command_bucket_id is present
              in the group specification then all buckets of the group
              are removed.

       dump-groups switch [group]
              Prints group entries in switch's tables to console.  To
              dump only a specific group, specify its number as group.
              Otherwise, if group is omitted, or if it is specified as
              ALL, then all groups are printed.

              Only OpenFlow 1.5 and later support dumping a specific
              group.  Earlier versions of OpenFlow always dump all
              groups.

       dump-group-features switch
              Prints to the console the group features of the switch.

       dump-group-stats switch [group]
              Prints to the console statistics for the specified group
              in switch's tables.  If group is omitted then statistics
              for all groups are printed.

   OpenFlow 1.3+ Switch Meter Table Commands
       These commands manage the meter table in an OpenFlow switch.  In
       each case, meter specifies a meter entry in the format described
       in Meter Syntax, below.

       OpenFlow 1.3 introduced support for meters, so these commands
       only work with switches that support OpenFlow 1.3 or later.  It
       is necessary to explicitly enable these protocol versions in
       ovs-ofctl (using -O) and in the switch itself (with the protocols
       column in the Bridge table).  For more information, see ``Q: What
       versions of OpenFlow does Open vSwitch support?'' in the Open
       vSwitch FAQ.

       add-meter switch meter
              Add a meter entry to switch's tables. The meter syntax is
              described in section Meter Syntax, below.

       mod-meter switch meter
              Modify an existing meter.

       del-meters switch [meter]
              Delete entries from switch's meter table.  To delete only
              a specific meter, specify its number as meter.  Otherwise,
              if meter is omitted, or if it is specified as all, then
              all meters are deleted.

       dump-meters switch [meter]
              Print entries from switch's meter table.  To print only a
              specific meter, specify its number as meter.  Otherwise,
              if meter is omitted, or if it is specified as all, then
              all meters are printed.

       meter-stats switch [meter]
              Print meter statistics.  meter can specify a single meter
              with syntax meter=id, or all meters with syntax meter=all.

       meter-features switch
              Print meter features.

   OpenFlow Switch Bundle Command
       Transactional updates to both flow and group tables can be made
       with the bundle command.  file is a text file that contains zero
       or more flow mods, group mods, or packet-outs in Flow Syntax,
       Group Syntax, or Packet-Out Syntax, each line preceded by flow,
       group, or packet-out keyword, correspondingly.  The flow keyword
       may be optionally followed by one of the keywords add, modify,
       modify_strict, delete, or delete_strict, of which the add is
       assumed if a bare flow is given.  Similarly, the group keyword
       may be optionally followed by one of the keywords add, modify,
       add_or_mod, delete, insert_bucket, or remove_bucket, of which the
       add is assumed if a bare group is given.

       bundle switch file
              Execute all flow and group mods in file as a single atomic
              transaction against switch's tables.  All bundled mods are
              executed in the order specified.

   OpenFlow Switch Tunnel TLV Table Commands
       Open vSwitch maintains a mapping table between tunnel option TLVs
       (defined by <class, type, length>) and NXM fields tun_metadatan,
       where n ranges from 0 to 63, that can be operated on for the
       purposes of matches, actions, etc. This TLV table can be used for
       Geneve option TLVs or other protocols with options in same TLV
       format as Geneve options. This mapping must be explicitly
       specified by the user through the following commands.

       A TLV mapping is specified with the syntax
       {class=class,type=type,len=length}->tun_metadatan.  When an
       option mapping exists for a given tun_metadatan, matching on the
       defined field becomes possible, e.g.:

              ovs-ofctl add-tlv-map br0
              "{class=0xffff,type=0,len=4}->tun_metadata0"

              ovs-ofctl add-flow br0
              tun_metadata0=1234,actions=controller

       A mapping should not be changed while it is in active use by a
       flow. The result of doing so is undefined.

       These commands are Nicira extensions to OpenFlow and require Open
       vSwitch 2.5 or later.

       add-tlv-map switch option[,option]...
              Add each option to switch's tables. Duplicate fields are
              rejected.

       del-tlv-map switch [option[,option]]...
              Delete each option from switch's table, or all option TLV
              mapping if no option is specified.  Fields that aren't
              mapped are ignored.

       dump-tlv-map switch
              Show the currently mapped fields in the switch's option
              table as well as switch capabilities.

   OpenFlow Switch Monitoring Commands
       snoop switch
              Connects to switch and prints to the console all OpenFlow
              messages received.  Unlike other ovs-ofctl commands, if
              switch is the name of a bridge, then the snoop command
              connects to a Unix domain socket named
              /usr/local/var/run/openvswitch/switch.snoop.  ovs-vswitchd
              listens on such a socket for each bridge and sends to it
              all of the OpenFlow messages sent to or received from its
              configured OpenFlow controller.  Thus, this command can be
              used to view OpenFlow protocol activity between a switch
              and its controller.

              When a switch has more than one controller configured,
              only the traffic to and from a single controller is
              output.  If none of the controllers is configured as a
              primary or a secondary (using a Nicira extension to
              OpenFlow 1.0 or 1.1, or a standard request in OpenFlow 1.2
              or later), then a controller is chosen arbitrarily among
              them.  If there is a primary controller, it is chosen;
              otherwise, if there are any controllers that are not
              primaries or secondaries, one is chosen arbitrarily;
              otherwise, a secondary controller is chosen arbitrarily.
              This choice is made once at connection time and does not
              change as controllers reconfigure their roles.

              If a switch has no controller configured, or if the
              configured controller is disconnected, no traffic is sent,
              so monitoring will not show any traffic.

       monitor switch [miss-len] [invalid_ttl] [watch:[spec...]]
              Connects to switch and prints to the console all OpenFlow
              messages received.  Usually, switch should specify the
              name of a bridge in the ovs-vswitchd database. This is
              available only in OpenFlow 1.0 as Nicira extension.

              If miss-len is provided, ovs-ofctl sends an OpenFlow ``set
              configuration'' message at connection setup time that
              requests miss-len bytes of each packet that misses the
              flow table.  Open vSwitch does not send these and other
              asynchronous messages to an ovs-ofctl monitor client
              connection unless a nonzero value is specified on this
              argument.  (Thus, if miss-len is not specified, very
              little traffic will ordinarily be printed.)

              If invalid_ttl is passed, ovs-ofctl sends an OpenFlow
              ``set configuration'' message at connection setup time
              that requests INVALID_TTL_TO_CONTROLLER, so that ovs-ofctl
              monitor can receive ``packet-in'' messages when TTL
              reaches zero on dec_ttl action.  Only OpenFlow 1.1 and 1.2
              support invalid_ttl; Open vSwitch also implements it for
              OpenFlow 1.0 as an extension.

              watch:[spec...] causes ovs-ofctl to send a ``monitor
              request'' Nicira extension message to the switch at
              connection setup time.  This message causes the switch to
              send information about flow table changes as they occur.
              The following comma-separated spec syntax is available:

              !initial
                     Do not report the switch's initial flow table
                     contents.

              !add   Do not report newly added flows.

              !delete
                     Do not report deleted flows.

              !modify
                     Do not report modifications to existing flows.

              !own   Abbreviate changes made to the flow table by
                     ovs-ofctl's own connection to the switch.  (These
                     could only occur using the ofctl/send command
                     described below under RUNTIME MANAGEMENT COMMANDS.)

              !actions
                     Do not report actions as part of flow updates.

              table=table
                     Limits the monitoring to the table with the given
                     table, which may be expressed as a number between 0
                     and 254 or (unless --no-names is specified) a name.
                     By default, all tables are monitored.

              out_port=port
                     If set, only flows that output to port are
                     monitored.  The port may be an OpenFlow port number
                     or keyword (e.g. LOCAL).

              field=value
                     Monitors only flows that have field specified as
                     the given value.  Any syntax valid for matching on
                     dump-flows may be used.

              This command may be useful for debugging switch or
              controller implementations.  With watch:, it is
              particularly useful for observing how a controller updates
              flow tables.

   OpenFlow Switch and Controller Commands
       The following commands, like those in the previous section, may
       be applied to OpenFlow switches, using any of the connection
       methods described in that section.  Unlike those commands, these
       may also be applied to OpenFlow controllers.

       probe target
              Sends a single OpenFlow echo-request message to target and
              waits for the response.  With the -t or --timeout option,
              this command can test whether an OpenFlow switch or
              controller is up and running.

       ping target [n]
              Sends a series of 10 echo request packets to target and
              times each reply.  The echo request packets consist of an
              OpenFlow header plus n bytes (default: 64) of randomly
              generated payload.  This measures the latency of
              individual requests.

       benchmark target n count
              Sends count echo request packets that each consist of an
              OpenFlow header plus n bytes of payload and waits for each
              response.  Reports the total time required.  This is a
              measure of the maximum bandwidth to target for round-trips
              of n-byte messages.

   Other Commands
       ofp-parse file
              Reads file (or stdin if file is -) as a series of OpenFlow
              messages in the binary format used on an OpenFlow
              connection, and prints them to the console.  This can be
              useful for printing OpenFlow messages captured from a TCP
              stream.

       ofp-parse-pcap file [port...]
              Reads file, which must be in the PCAP format used by
              network capture tools such as tcpdump or wireshark,
              extracts all the TCP streams for OpenFlow connections, and
              prints the OpenFlow messages in those connections in
              human-readable format on stdout.

              OpenFlow connections are distinguished by TCP port number.
              Non-OpenFlow packets are ignored.  By default, data on TCP
              ports 6633 and 6653 are considered to be OpenFlow.
              Specify one or more port arguments to override the
              default.

              This command cannot usefully print SSL encrypted traffic.
              It does not understand IPv6.

   Flow Syntax
       Some ovs-ofctl commands accept an argument that describes a flow
       or flows.  Such flow descriptions comprise a series of
       field=value assignments, separated by commas or white space.
       (Embedding spaces into a flow description normally requires
       quoting to prevent the shell from breaking the description into
       multiple arguments.)

       Flow descriptions should be in normal form.  This means that a
       flow may only specify a value for an L3 field if it also
       specifies a particular L2 protocol, and that a flow may only
       specify an L4 field if it also specifies particular L2 and L3
       protocol types.  For example, if the L2 protocol type dl_type is
       wildcarded, then L3 fields nw_src, nw_dst, and nw_proto must also
       be wildcarded.  Similarly, if dl_type or nw_proto (the L3
       protocol type) is wildcarded, so must be the L4 fields tcp_dst
       and tcp_src.  ovs-ofctl will warn about flows not in normal form.

       ovs-fields(7) describes the supported fields and how to match
       them.  In addition to match fields, commands that operate on
       flows accept a few additional key-value pairs:

       table=table
              For flow dump commands, limits the flows dumped to those
              in table, which may be expressed as a number between 0 and
              255 or (unless --no-names is specified) a name.  If not
              specified (or if 255 is specified as table), then flows in
              all tables are dumped.

              For flow table modification commands, behavior varies
              based on the OpenFlow version used to connect to the
              switch:

              OpenFlow 1.0
                     OpenFlow 1.0 does not support table for modifying
                     flows.  ovs-ofctl will exit with an error if table
                     (other than table=255) is specified for a switch
                     that only supports OpenFlow 1.0.

                     In OpenFlow 1.0, the switch chooses the table into
                     which to insert a new flow.  The Open vSwitch
                     software switch always chooses table 0.  Other Open
                     vSwitch datapaths and other OpenFlow
                     implementations may choose different tables.

                     The OpenFlow 1.0 behavior in Open vSwitch for
                     modifying or removing flows depends on whether
                     --strict is used.  Without --strict, the command
                     applies to matching flows in all tables.  With
                     --strict, the command will operate on any single
                     matching flow in any table; it will do nothing if
                     there are matches in more than one table.  (The
                     distinction between these behaviors only matters if
                     non-OpenFlow 1.0 commands were also used, because
                     OpenFlow 1.0 alone cannot add flows with the same
                     matching criteria to multiple tables.)

              OpenFlow 1.0 with table_id extension
                     Open vSwitch implements an OpenFlow extension that
                     allows the controller to specify the table on which
                     to operate.  ovs-ofctl automatically enables the
                     extension when table is specified and OpenFlow 1.0
                     is used.  ovs-ofctl automatically detects whether
                     the switch supports the extension.  As of this
                     writing, this extension is only known to be
                     implemented by Open vSwitch.

                     With this extension, ovs-ofctl operates on the
                     requested table when table is specified, and acts
                     as described for OpenFlow 1.0 above when no table
                     is specified (or for table=255).

              OpenFlow 1.1
                     OpenFlow 1.1 requires flow table modification
                     commands to specify a table.  When table is not
                     specified (or table=255 is specified), ovs-ofctl
                     defaults to table 0.

              OpenFlow 1.2 and later
                     OpenFlow 1.2 and later allow flow deletion
                     commands, but not other flow table modification
                     commands, to operate on all flow tables, with the
                     behavior described above for OpenFlow 1.0.

       duration=...
       n_packet=...
       n_bytes=...
              ovs-ofctl ignores assignments to these ``fields'' to allow
              output from the dump-flows command to be used as input for
              other commands that parse flows.

       The add-flow, add-flows, and mod-flows commands require an
       additional field, which must be the final field specified:

       actions=[action][,action...]
              Specifies a comma-separated list of actions to take on a
              packet when the flow entry matches.  If no action is
              specified, then packets matching the flow are dropped.
              See ovs-actions(7) for details on the syntax and semantics
              of actions.  K

       An opaque identifier called a cookie can be used as a handle to
       identify a set of flows:

       cookie=value
              A cookie can be associated with a flow using the add-flow,
              add-flows, and mod-flows commands.  value can be any
              64-bit number and need not be unique among flows.  If this
              field is omitted, a default cookie value of 0 is used.

       cookie=value/mask
              When using NXM, the cookie can be used as a handle for
              querying, modifying, and deleting flows.  value and mask
              may be supplied for the del-flows, mod-flows, dump-flows,
              and dump-aggregate commands to limit matching cookies.  A
              1-bit in mask indicates that the corresponding bit in
              cookie must match exactly, and a 0-bit wildcards that bit.
              A mask of -1 may be used to exactly match a cookie.

              The mod-flows command can update the cookies of flows that
              match a cookie by specifying the cookie field twice (once
              with a mask for matching and once without to indicate the
              new value):

              ovs-ofctl mod-flows br0 cookie=1,actions=normal
                     Change all flows' cookies to 1 and change their
                     actions to normal.

              ovs-ofctl mod-flows br0
              cookie=1/-1,cookie=2,actions=normal
                     Update cookies with a value of 1 to 2 and change
                     their actions to normal.

              The ability to match on cookies was added in Open vSwitch
              1.5.0.

       The following additional field sets the priority for flows added
       by the add-flow and add-flows commands.  For mod-flows and
       del-flows when --strict is specified, priority must match along
       with the rest of the flow specification.  For mod-flows without
       --strict, priority is only significant if the command creates a
       new flow, that is, non-strict mod-flows does not match on
       priority and will not change the priority of existing flows.
       Other commands do not allow priority to be specified.

       priority=value
              The priority at which a wildcarded entry will match in
              comparison to others.  value is a number between 0 and
              65535, inclusive.  A higher value will match before a
              lower one.  An exact-match entry will always have priority
              over an entry containing wildcards, so it has an implicit
              priority value of 65535.  When adding a flow, if the field
              is not specified, the flow's priority will default to
              32768.

              OpenFlow leaves behavior undefined when two or more flows
              with the same priority can match a single packet.  Some
              users expect ``sensible'' behavior, such as more specific
              flows taking precedence over less specific flows, but
              OpenFlow does not specify this and Open vSwitch does not
              implement it.  Users should therefore take care to use
              priorities to ensure the behavior that they expect.

       The add-flow, add-flows, and mod-flows commands support the
       following additional options.  These options affect only new
       flows.  Thus, for add-flow and add-flows, these options are
       always significant, but for mod-flows they are significant only
       if the command creates a new flow, that is, their values do not
       update or affect existing flows.

       idle_timeout=seconds
              Causes the flow to expire after the given number of
              seconds of inactivity.  A value of 0 (the default)
              prevents a flow from expiring due to inactivity.

       hard_timeout=seconds
              Causes the flow to expire after the given number of
              seconds, regardless of activity.  A value of 0 (the
              default) gives the flow no hard expiration deadline.

       importance=value
              Sets the importance of a flow.  The flow entry eviction
              mechanism can use importance as a factor in deciding which
              flow to evict.  A value of 0 (the default) makes the flow
              non-evictable on the basis of importance.  Specify a value
              between 0 and 65535.

              Only OpenFlow 1.4 and later support importance.

       send_flow_rem
              Marks the flow with a flag that causes the switch to
              generate a ``flow removed'' message and send it to
              interested controllers when the flow later expires or is
              removed.

       check_overlap
              Forces the switch to check that the flow match does not
              overlap that of any different flow with the same priority
              in the same table.  (This check is expensive so it is best
              to avoid it.)

       reset_counts
              When this flag is specified on a flow being added to a
              switch, and the switch already has a flow with an
              identical match, an OpenFlow 1.2 (or later) switch resets
              the flow's packet and byte counters to 0.  Without the
              flag, the packet and byte counters are preserved.

              OpenFlow 1.0 and 1.1 switches always reset counters in
              this situation, as if reset_counts were always specified.

              Open vSwitch 1.10 added support for reset_counts.

       no_packet_counts
       no_byte_counts
              Adding these flags to a flow advises an OpenFlow 1.3 (or
              later) switch that the controller does not need packet or
              byte counters, respectively, for the flow.  Some switch
              implementations might achieve higher performance or reduce
              resource consumption when these flags are used.  These
              flags provide no benefit to the Open vSwitch software
              switch implementation.

              OpenFlow 1.2 and earlier do not support these flags.

              Open vSwitch 1.10 added support for no_packet_counts and
              no_byte_counts.

       The dump-flows, dump-aggregate, del-flow and del-flows commands
       support these additional optional fields:

       out_port=port
              If set, a matching flow must include an output action to
              port, which must be an OpenFlow port number or name (e.g.
              local).

       out_group=group
              If set, a matching flow must include an group action
              naming group, which must be an OpenFlow group number.
              This field is supported in Open vSwitch 2.5 and later and
              requires OpenFlow 1.1 or later.

   Table Entry Output
       The dump-tables and dump-aggregate commands print information
       about the entries in a datapath's tables.  Each line of output is
       a flow entry as described in Flow Syntax, above, plus some
       additional fields:

       duration=secs
              The time, in seconds, that the entry has been in the
              table.  secs includes as much precision as the switch
              provides, possibly to nanosecond resolution.

       n_packets
              The number of packets that have matched the entry.

       n_bytes
              The total number of bytes from packets that have matched
              the entry.

       The following additional fields are included only if the switch
       is Open vSwitch 1.6 or later and the NXM flow format is used to
       dump the flow (see the description of the --flow-format option
       below).  The values of these additional fields are approximations
       only and in particular idle_age will sometimes become nonzero
       even for busy flows.

       hard_age=secs
              The integer number of seconds since the flow was added or
              modified.  hard_age is displayed only if it differs from
              the integer part of duration.  (This is separate from
              duration because mod-flows restarts the hard_timeout timer
              without zeroing duration.)

       idle_age=secs
              The integer number of seconds that have passed without any
              packets passing through the flow.

   Packet-Out Syntax
       ovs-ofctl bundle command accepts packet-outs to be specified in
       the bundle file.  Each packet-out comprises of a series of
       field=value assignments, separated by commas or white space.
       (Embedding spaces into a packet-out description normally requires
       quoting to prevent the shell from breaking the description into
       multiple arguments.).  Unless noted otherwise only the last
       instance of each field is honoured.  This same syntax is also
       supported by the ovs-ofctl packet-out command.

       in_port=port
              The port number to be considered the in_port when
              processing actions.  This can be any valid OpenFlow port
              number, or any of the LOCAL, CONTROLLER, or NONE.  This
              field is required.

       pipeline_field=value
              Optionally, user can specify a list of pipeline fields for
              a packet-out message. The supported pipeline fields
              includes tunnel fields and register fields as defined in
              ovs-fields(7).

       packet=hex-string
              The actual packet to send, expressed as a string of
              hexadecimal bytes.  This field is required.

       actions=[action][,action...]
              The syntax of actions are identical to the actions= field
              described in Flow Syntax above.  Specifying actions= is
              optional, but omitting actions is interpreted as a drop,
              so the packet will not be sent anywhere from the switch.
              actions must be specified at the end of each line, like
              for flow mods.

   Group Syntax
       Some ovs-ofctl commands accept an argument that describes a group
       or groups.  Such flow descriptions comprise a series field=value
       assignments, separated by commas or white space.  (Embedding
       spaces into a group description normally requires quoting to
       prevent the shell from breaking the description into multiple
       arguments.). Unless noted otherwise only the last instance of
       each field is honoured.

       group_id=id
              The integer group id of group.  When this field is
              specified in del-groups or dump-groups, the keyword "all"
              may be used to designate all groups.  This field is
              required.

       type=type
              The type of the group.  The add-group, add-groups and mod-
              groups commands require this field.  It is prohibited for
              other commands. The following keywords designated the
              allowed types:

              all    Execute all buckets in the group.

              select Execute one bucket in the group, balancing across
                     the buckets according to their weights.  To select
                     a bucket, for each live bucket, Open vSwitch hashes
                     flow data with the bucket ID and multiplies by the
                     bucket weight to obtain a ``score,'' and then
                     selects the bucket with the highest score.  Use
                     selection_method to control the flow data used for
                     selection.

              indirect
                     Executes the one bucket in the group.

              ff
              fast_failover
                     Executes the first live bucket in the group which
                     is associated with a live port or group.

       command_bucket_id=id
              The bucket to operate on.  The insert-buckets and remove-
              buckets commands require this field.  It is prohibited for
              other commands.  id may be an integer or one of the
              following keywords:

              all    Operate on all buckets in the group.  Only valid
                     when used with the remove-buckets command in which
                     case the effect is to remove all buckets from the
                     group.

              first  Operate on the first bucket present in the group.
                     In the case of the insert-buckets command the
                     effect is to insert new bucets just before the
                     first bucket already present in the group; or to
                     replace the buckets of the group if there are no
                     buckets already present in the group.  In the case
                     of the remove-buckets command the effect is to
                     remove the first bucket of the group; or do nothing
                     if there are no buckets present in the group.

              last   Operate on the last bucket present in the group.
                     In the case of the insert-buckets command the
                     effect is to insert new bucets just after the last
                     bucket already present in the group; or to replace
                     the buckets of the group if there are no buckets
                     already present in the group.  In the case of the
                     remove-buckets command the effect is to remove the
                     last bucket of the group; or do nothing if there
                     are no buckets present in the group.

              If id is an integer then it should correspond to the
              bucket_id of a bucket present in the group.  In case of
              the insert-buckets command the effect is to insert buckets
              just before the bucket in the group whose bucket_id is id.
              In case of the iremove-buckets command the effect is to
              remove the in the group whose bucket_id is id.  It is an
              error if there is no bucket persent group in whose
              bucket_id is id.

       selection_method=method
              The selection method used to select a bucket for a select
              group.  This is a string of 1 to 15 bytes in length known
              to lower layers.  This field is optional for add-group,
              add-groups and mod-group commands on groups of type
              select. Prohibited otherwise.  If no selection method is
              specified, Open vSwitch up to release 2.9 applies the hash
              method with default fields. From 2.10 onwards Open vSwitch
              defaults to the dp_hash method with symmetric L3/L4 hash
              algorithm, unless the weighted group buckets cannot be
              mapped to a maximum of 64 dp_hash values with sufficient
              accuracy.  In those rare cases Open vSwitch 2.10 and later
              fall back to the hash method with the default set of hash
              fields.

              dp_hash
                     Use a datapath computed hash value.  The hash
                     algorithm varies accross different datapath
                     implementations.  dp_hash uses the upper 32 bits of
                     the selection_method_param as the datapath hash
                     algorithm selector.  The supported values are 0
                     (corresponding to hash computation over the IP
                     5-tuple) and 1 (corresponding to a symmetric hash
                     computation over the IP 5-tuple).  Selecting
                     specific fields with the fields option is not
                     supported with dp_hash).  The lower 32 bits are
                     used as the hash basis.

                     Using dp_hash has the advantage that it does not
                     require the generated datapath flows to exact match
                     any additional packet header fields.  For example,
                     even if multiple TCP connections thus hashed to
                     different select group buckets have different
                     source port numbers, generally all of them would be
                     handled with a small set of already established
                     datapath flows, resulting in less latency for TCP
                     SYN packets.  The downside is that the shared
                     datapath flows must match each packet twice, as the
                     datapath hash value calculation happens only when
                     needed, and a second match is required to match
                     some bits of its value.  This double-matching
                     incurs a small additional latency cost for each
                     packet, but this latency is orders of magnitude
                     less than the latency of creating new datapath
                     flows for new TCP connections.

              hash   Use a hash computed over the fields specified with
                     the fields option, see below.  If no hash fields
                     are specified, hash defaults to a symmetric hash
                     over the combination of MAC addresses, VLAN tags,
                     Ether type, IP addresses and L4 port numbers.  hash
                     uses the selection_method_param as the hash basis.

                     Note that the hashed fields become exact matched by
                     the datapath flows.  For example, if the TCP source
                     port is hashed, the created datapath flows will
                     match the specific TCP source port value present in
                     the packet received.  Since each TCP connection
                     generally has a different source port value, a
                     separate datapath flow will be need to be inserted
                     for each TCP connection thus hashed to a select
                     group bucket.

              This option uses a Netronome OpenFlow extension which is
              only supported when using Open vSwitch 2.4 and later with
              OpenFlow 1.5 and later.

       selection_method_param=param
              64-bit integer parameter to the selection method selected
              by the selection_method field.  The parameter's use is
              defined by the lower-layer that implements the
              selection_method.  It is optional if the selection_method
              field is specified as a non-empty string.  Prohibited
              otherwise. The default value is zero.

              This option uses a Netronome OpenFlow extension which is
              only supported when using Open vSwitch 2.4 and later with
              OpenFlow 1.5 and later.

       fields=field
       fields(field[=mask]...)
              The field parameters to selection method selected by the
              selection_method field.  The syntax is described in Flow
              Syntax with the additional restrictions that if a value is
              provided it is treated as a wildcard mask and wildcard
              masks following a slash are prohibited. The pre-requisites
              of fields must be provided by any flows that output to the
              group.  The use of the fields is defined by the lower-
              layer that implements the selection_method.  They are
              optional if the selection_method field is specified as
              ``hash', prohibited otherwise.  The default is no fields.

              This option will use a Netronome OpenFlow extension which
              is only supported when using Open vSwitch 2.4 and later
              with OpenFlow 1.5 and later.

       bucket=bucket_parameters
              The add-group, add-groups and mod-group commands require
              at least one bucket field. Bucket fields must appear after
              all other fields.  Multiple bucket fields to specify
              multiple buckets.  The order in which buckets are
              specified corresponds to their order in the group. If the
              type of the group is "indirect" then only one group may be
              specified.  bucket_parameters consists of a list of
              field=value assignments, separated by commas or white
              space followed by a comma-separated list of actions.  The
              fields for bucket_parameters are:

              bucket_id=id
                     The 32-bit integer group id of the bucket.  Values
                     greater than 0xffffff00 are reserved.  This field
                     was added in Open vSwitch 2.4 to conform with the
                     OpenFlow 1.5 specification. It is not supported
                     when earlier versions of OpenFlow are used.  Open
                     vSwitch will automatically allocate bucket ids when
                     they are not specified.

              actions=[action][,action...]
                     The syntax of actions are identical to the actions=
                     field described in Flow Syntax above. Specifying
                     actions= is optional, any unknown bucket parameter
                     will be interpreted as an action.

              weight=value
                     The relative weight of the bucket as an integer.
                     This may be used by the switch during bucket select
                     for groups whose type is select.

              watch_port=port
                     Port used to determine liveness of group.  This or
                     the watch_group field is required for groups whose
                     type is ff or fast_failover.  This or the
                     watch_group field can also be used for groups whose
                     type is select.

              watch_group=group_id
                     Group identifier of group used to determine
                     liveness of group.  This or the watch_port field is
                     required for groups whose type is ff or
                     fast_failover.  This or the watch_port field can
                     also be used for groups whose type is select.

   Meter Syntax
       The meter table commands accept an argument that describes a
       meter.  Such meter descriptions comprise a series field=value
       assignments, separated by commas or white space.  (Embedding
       spaces into a group description normally requires quoting to
       prevent the shell from breaking the description into multiple
       arguments.). Unless noted otherwise only the last instance of
       each field is honoured.

       meter=id
              The identifier for the meter.  An integer is used to
              specify a user-defined meter.  In addition, the keywords
              "all", "controller", and "slowpath", are also supported as
              virtual meters.  The "controller" and "slowpath" virtual
              meters apply to packets sent to the controller and to the
              OVS userspace, respectively.

              When this field is specified in del-meter, dump-meter, or
              meter-stats, the keyword "all" may be used to designate
              all meters.  This field is required, except for meter-
              stats, which dumps all stats when this field is not
              specified.

       kbps
       pktps  The unit for the rate and burst_size band parameters.
              kbps specifies kilobits per second, and pktps specifies
              packets per second.  A unit is required for the add-meter
              and mod-meter commands.

       burst  If set, enables burst support for meter bands through the
              burst_size parameter.

       stats  If set, enables the collection of meter and band
              statistics.

       bands=band_parameters
              The add-meter and mod-meter commands require at least one
              band specification. Bands must appear after all other
              fields.

              type=type
                     The type of the meter band.  This keyword starts a
                     new band specification.  Each band specifies a rate
                     above which the band is to take some action. The
                     action depends on the band type.  If multiple
                     bands' rate is exceeded, then the band with the
                     highest rate among the exceeded bands is selected.
                     The following keywords designate the allowed meter
                     band types:

                     drop   Drop packets exceeding the band's rate
                            limit.

              The other band_parameters are:

              rate=value
                     The relative rate limit for this band, in kilobits
                     per second or packets per second, depending on
                     whether kbps or pktps was specified.

              burst_size=size
                     If burst is specified for the meter entry,
                     configures the maximum burst allowed for the band
                     in kilobits or packets, depending on whether kbps
                     or pktps was specified.  If unspecified, the switch
                     is free to select some reasonable value depending
                     on its configuration.

OPTIONS         top

       --strict
              Uses strict matching when running flow modification
              commands.

       --names
       --no-names
              Every OpenFlow port has a name and a number, and every
              OpenFlow flow table has a number and sometimes a name.  By
              default, ovs-ofctl commands accept both port and table
              names and numbers, and they display port and table names
              if ovs-ofctl is running on an interactive console, numbers
              otherwise.  With --names, ovs-ofctl commands both accept
              and display port and table names; with --no-names,
              commands neither accept nor display port and table names.

              If a port or table name contains special characters or
              might be confused with a keyword within a flow, it may be
              enclosed in double quotes (escaped from the shell).  If
              necessary, JSON-style escape sequences may be used inside
              quotes, as specified in RFC 7159.  When it displays port
              and table names, ovs-ofctl quotes any name that does not
              start with a letter followed by letters or digits.

              Open vSwitch added support for port names and these
              options.  Open vSwitch 2.10 added support for table names.
              Earlier versions always behaved as if --no-names were
              specified.

              Open vSwitch does not place its own limit on the length of
              port names, but OpenFlow limits port names to 15 bytes.
              Because ovs-ofctl uses OpenFlow to retrieve the mapping
              between port names and numbers, names longer than this
              limit will be truncated for both display and acceptance.
              Truncation can also cause long names that are different to
              appear to be the same; when a switch has two ports with
              the same (truncated) name, ovs-ofctl refuses to display or
              accept the name, using the number instead.

              OpenFlow and Open vSwitch limit table names to 32 bytes.

       --stats
       --no-stats
              The dump-flows command by default, or with --stats,
              includes flow duration, packet and byte counts, and idle
              and hard age in its output.  With --no-stats, it omits all
              of these, as well as cookie values and table IDs if they
              are zero.

       --read-only
              Do not execute read/write commands.

       --bundle
              Execute flow mods as an OpenFlow 1.4 atomic bundle
              transaction.

              •      Within a bundle, all flow mods are processed in the
                     order they appear and as a single atomic
                     transaction, meaning that if one of them fails, the
                     whole transaction fails and none of the changes are
                     made to the switch's flow table, and that each
                     given datapath packet traversing the OpenFlow
                     tables sees the flow tables either as before the
                     transaction, or after all the flow mods in the
                     bundle have been successfully applied.

              •      The beginning and the end of the flow table
                     modification commands in a bundle are delimited
                     with OpenFlow 1.4 bundle control messages, which
                     makes it possible to stream the included commands
                     without explicit OpenFlow barriers, which are
                     otherwise used after each flow table modification
                     command.  This may make large modifications execute
                     faster as a bundle.

              •      Bundles require OpenFlow 1.4 or higher.  An
                     explicit -O OpenFlow14 option is not needed, but
                     you may need to enable OpenFlow 1.4 support for OVS
                     by setting the OVSDB protocols column in the bridge
                     table.

       -O [version[,version]...]
       --protocols=[version[,version]...]
              Sets the OpenFlow protocol versions that are allowed when
              establishing an OpenFlow session.

              These protocol versions are enabled by default:

              •      OpenFlow10, for OpenFlow 1.0.
       The following protocol versions are generally supported, but for
       compatibility with older versions of Open vSwitch they are not
       enabled by default:

              •      OpenFlow11, for OpenFlow 1.1.

              •      OpenFlow12, for OpenFlow 1.2.

              •      OpenFlow13, for OpenFlow 1.3.

              •      OpenFlow14, for OpenFlow 1.4.

              •      OpenFlow15, for OpenFlow 1.5.

       -F format[,format...]
       --flow-format=format[,format...]
              ovs-ofctl supports the following individual flow formats,
              any number of which may be listed as format:

              OpenFlow10-table_id
                     This is the standard OpenFlow 1.0 flow format.  All
                     OpenFlow switches and all versions of Open vSwitch
                     support this flow format.

              OpenFlow10+table_id
                     This is the standard OpenFlow 1.0 flow format plus
                     a Nicira extension that allows ovs-ofctl to specify
                     the flow table in which a particular flow should be
                     placed.  Open vSwitch 1.2 and later supports this
                     flow format.

              NXM-table_id (Nicira Extended Match)
                     This Nicira extension to OpenFlow is flexible and
                     extensible.  It supports all of the Nicira flow
                     extensions, such as tun_id and registers.  Open
                     vSwitch 1.1 and later supports this flow format.

              NXM+table_id (Nicira Extended Match)
                     This combines Nicira Extended match with the
                     ability to place a flow in a specific table.  Open
                     vSwitch 1.2 and later supports this flow format.

              OXM-OpenFlow12
              OXM-OpenFlow13
              OXM-OpenFlow14
              OXM-OpenFlow15
                     These are the standard OXM (OpenFlow Extensible
                     Match) flow format in OpenFlow 1.2 and later.

              ovs-ofctl also supports the following abbreviations for
              collections of flow formats:

              any    Any supported flow format.

              OpenFlow10
                     OpenFlow10-table_id or OpenFlow10+table_id.

              NXM    NXM-table_id or NXM+table_id.

              OXM    OXM-OpenFlow12, OXM-OpenFlow13, or OXM-OpenFlow14.

              For commands that modify the flow table, ovs-ofctl by
              default negotiates the most widely supported flow format
              that supports the flows being added.  For commands that
              query the flow table, ovs-ofctl by default uses the most
              advanced format supported by the switch.

              This option, where format is a comma-separated list of one
              or more of the formats listed above, limits ovs-ofctl's
              choice of flow format.  If a command cannot work as
              requested using one of the specified flow formats,
              ovs-ofctl will report a fatal error.

       -P format
       --packet-in-format=format
              ovs-ofctl supports the following ``packet-in'' formats, in
              order of increasing capability:

              standard
                     This uses the OFPT_PACKET_IN message, the standard
                     ``packet-in'' message for any given OpenFlow
                     version.  Every OpenFlow switch that supports a
                     given OpenFlow version supports this format.

              nxt_packet_in
                     This uses the NXT_PACKET_IN message, which adds
                     many of the capabilities of the OpenFlow 1.1 and
                     later ``packet-in'' messages before those OpenFlow
                     versions were available in Open vSwitch.  Open
                     vSwitch 1.1 and later support this format.  Only
                     Open vSwitch 2.6 and later, however, support it for
                     OpenFlow 1.1 and later (but there is little reason
                     to use it with those versions of OpenFlow).

              nxt_packet_in2
                     This uses the NXT_PACKET_IN2 message, which is
                     extensible and should avoid the need to define new
                     formats later.  In particular, this format supports
                     passing arbitrary user-provided data to a
                     controller using the userdata option on the
                     controller action.  Open vSwitch 2.6 and later
                     support this format.

              Without this option, ovs-ofctl prefers nxt_packet_in2 if
              the switch supports it.  Otherwise, if OpenFlow 1.0 is in
              use, ovs-ofctl prefers nxt_packet_in if the switch
              supports it.  Otherwise, ovs-ofctl falls back to the
              standard packet-in format.  When this option is specified,
              ovs-ofctl insists on the selected format.  If the switch
              does not support the requested format, ovs-ofctl will
              report a fatal error.

              Before version 2.6, Open vSwitch called standard format
              openflow10 and nxt_packet_in format nxm, and ovs-ofctl
              still accepts these names as synonyms.  (The name
              openflow10 was a misnomer because this format actually
              varies from one OpenFlow version to another; it is not
              consistently OpenFlow 1.0 format.  Similarly, when
              nxt_packet_in2 was introduced, the name nxm became
              confusing because it also uses OXM/NXM.)

              This option affects only the monitor command.

       --timestamp
              Print a timestamp before each received packet.  This
              option only affects the monitor, snoop, and ofp-parse-pcap
              commands.

       -m
       --more Increases the verbosity of OpenFlow messages printed and
              logged by ovs-ofctl commands.  Specify this option more
              than once to increase verbosity further.

       --sort[=field]
       --rsort[=field]
              Display output sorted by flow field in ascending (--sort)
              or descending (--rsort) order, where field is any of the
              fields that are allowed for matching or priority to sort
              by priority.  When field is omitted, the output is sorted
              by priority.  Specify these options multiple times to sort
              by multiple fields.

              Any given flow will not necessarily specify a value for a
              given field.  This requires special treatement:

              •      A flow that does not specify any part of a field
                     that is used for sorting is sorted after all the
                     flows that do specify the field.  For example,
                     --sort=tcp_src will sort all the flows that specify
                     a TCP source port in ascending order, followed by
                     the flows that do not specify a TCP source port at
                     all.

              •      A flow that only specifies some bits in a field is
                     sorted as if the wildcarded bits were zero.  For
                     example, --sort=nw_src would sort a flow that
                     specifies nw_src=192.168.0.0/24 the same as
                     nw_src=192.168.0.0.

              These options currently affect only dump-flows output.

   Daemon Options
       The following options are valid on POSIX based platforms.

       --pidfile[=pidfile]
              Causes a file (by default, ovs-ofctl.pid) to be created
              indicating the PID of the running process.  If the pidfile
              argument is not specified, or if it does not begin with /,
              then it is created in /usr/local/var/run/openvswitch.

              If --pidfile is not specified, no pidfile is created.

       --overwrite-pidfile
              By default, when --pidfile is specified and the specified
              pidfile already exists and is locked by a running process,
              ovs-ofctl refuses to start.  Specify --overwrite-pidfile
              to cause it to instead overwrite the pidfile.

              When --pidfile is not specified, this option has no
              effect.

       --detach
              Runs ovs-ofctl as a background process.  The process
              forks, and in the child it starts a new session, closes
              the standard file descriptors (which has the side effect
              of disabling logging to the console), and changes its
              current directory to the root (unless --no-chdir is
              specified).  After the child completes its initialization,
              the parent exits.  ovs-ofctl detaches only when executing
              the monitor or snoop commands.

       --monitor
              Creates an additional process to monitor the ovs-ofctl
              daemon.  If the daemon dies due to a signal that indicates
              a programming error (SIGABRT, SIGALRM, SIGBUS, SIGFPE,
              SIGILL, SIGPIPE, SIGSEGV, SIGXCPU, or SIGXFSZ) then the
              monitor process starts a new copy of it.  If the daemon
              dies or exits for another reason, the monitor process
              exits.

              This option is normally used with --detach, but it also
              functions without it.

       --no-chdir
              By default, when --detach is specified, ovs-ofctl changes
              its current working directory to the root directory after
              it detaches.  Otherwise, invoking ovs-ofctl from a
              carelessly chosen directory would prevent the
              administrator from unmounting the file system that holds
              that directory.

              Specifying --no-chdir suppresses this behavior, preventing
              ovs-ofctl from changing its current working directory.
              This may be useful for collecting core files, since it is
              common behavior to write core dumps into the current
              working directory and the root directory is not a good
              directory to use.

              This option has no effect when --detach is not specified.

       --no-self-confinement
              By default daemon will try to self-confine itself to work
              with files under well-known directories determined during
              build.  It is better to stick with this default behavior
              and not to use this flag unless some other Access Control
              is used to confine daemon.  Note that in contrast to other
              access control implementations that are typically enforced
              from kernel-space (e.g. DAC or MAC), self-confinement is
              imposed from the user-space daemon itself and hence should
              not be considered as a full confinement strategy, but
              instead should be viewed as an additional layer of
              security.

       --user Causes ovs-ofctl to run as a different user specified in
              "user:group", thus dropping most of the root privileges.
              Short forms "user" and ":group" are also allowed, with
              current user or group are assumed respectively. Only
              daemons started by the root user accepts this argument.

              On Linux, daemons will be granted CAP_IPC_LOCK and
              CAP_NET_BIND_SERVICES before dropping root privileges.
              Daemons that interact with a datapath, such as
              ovs-vswitchd, will be granted three additional
              capabilities, namely CAP_NET_ADMIN, CAP_NET_BROADCAST and
              CAP_NET_RAW.  The capability change will apply even if the
              new user is root.

              On Windows, this option is not currently supported. For
              security reasons, specifying this option will cause the
              daemon process not to start.

       --unixctl=socket
              Sets the name of the control socket on which ovs-ofctl
              listens for runtime management commands (see RUNTIME
              MANAGEMENT COMMANDS, below).  If socket does not begin
              with /, it is interpreted as relative to
              /usr/local/var/run/openvswitch.  If --unixctl is not used
              at all, the default socket is
              /usr/local/var/run/openvswitch/ovs-ofctl.pid.ctl, where
              pid is ovs-ofctl's process ID.

              On Windows a local named pipe is used to listen for
              runtime management commands.  A file is created in the
              absolute path as pointed by socket or if --unixctl is not
              used at all, a file is created as ovs-ofctl.ctl in the
              configured OVS_RUNDIR directory.  The file exists just to
              mimic the behavior of a Unix domain socket.

              Specifying none for socket disables the control socket
              feature.

   Public Key Infrastructure Options
       -p privkey.pem
       --private-key=privkey.pem
              Specifies a PEM file containing the private key used as
              ovs-ofctl's identity for outgoing SSL connections.

       -c cert.pem
       --certificate=cert.pem
              Specifies a PEM file containing a certificate that
              certifies the private key specified on -p or --private-key
              to be trustworthy.  The certificate must be signed by the
              certificate authority (CA) that the peer in SSL
              connections will use to verify it.

       -C cacert.pem
       --ca-cert=cacert.pem
              Specifies a PEM file containing the CA certificate that
              ovs-ofctl should use to verify certificates presented to
              it by SSL peers.  (This may be the same certificate that
              SSL peers use to verify the certificate specified on -c or
              --certificate, or it may be a different one, depending on
              the PKI design in use.)

       -C none
       --ca-cert=none
              Disables verification of certificates presented by SSL
              peers.  This introduces a security risk, because it means
              that certificates cannot be verified to be those of known
              trusted hosts.

       -v[spec]
       --verbose=[spec]
              Sets logging levels.  Without any spec, sets the log level
              for every module and destination to dbg.  Otherwise, spec
              is a list of words separated by spaces or commas or
              colons, up to one from each category below:

              •      A valid module name, as displayed by the vlog/list
                     command on ovs-appctl(8), limits the log level
                     change to the specified module.

              •      syslog, console, or file, to limit the log level
                     change to only to the system log, to the console,
                     or to a file, respectively.  (If --detach is
                     specified, ovs-ofctl closes its standard file
                     descriptors, so logging to the console will have no
                     effect.)

                     On Windows platform, syslog is accepted as a word
                     and is only useful along with the --syslog-target
                     option (the word has no effect otherwise).

              •      off, emer, err, warn, info, or dbg, to control the
                     log level.  Messages of the given severity or
                     higher will be logged, and messages of lower
                     severity will be filtered out.  off filters out all
                     messages.  See ovs-appctl(8) for a definition of
                     each log level.

              Case is not significant within spec.

              Regardless of the log levels set for file, logging to a
              file will not take place unless --log-file is also
              specified (see below).

              For compatibility with older versions of OVS, any is
              accepted as a word but has no effect.

       -v
       --verbose
              Sets the maximum logging verbosity level, equivalent to
              --verbose=dbg.

       -vPATTERN:destination:pattern
       --verbose=PATTERN:destination:pattern
              Sets the log pattern for destination to pattern.  Refer to
              ovs-appctl(8) for a description of the valid syntax for
              pattern.

       -vFACILITY:facility
       --verbose=FACILITY:facility
              Sets the RFC5424 facility of the log message. facility can
              be one of kern, user, mail, daemon, auth, syslog, lpr,
              news, uucp, clock, ftp, ntp, audit, alert, clock2, local0,
              local1, local2, local3, local4, local5, local6 or local7.
              If this option is not specified, daemon is used as the
              default for the local system syslog and local0 is used
              while sending a message to the target provided via the
              --syslog-target option.

       --log-file[=file]
              Enables logging to a file.  If file is specified, then it
              is used as the exact name for the log file.  The default
              log file name used if file is omitted is
              /usr/local/var/log/openvswitch/ovs-ofctl.log.

       --syslog-target=host:port
              Send syslog messages to UDP port on host, in addition to
              the system syslog.  The host must be a numerical IP
              address, not a hostname.

       --syslog-method=method
              Specify method how syslog messages should be sent to
              syslog daemon.  Following forms are supported:

              •      libc, use libc syslog() function.  Downside of
                     using this options is that libc adds fixed prefix
                     to every message before it is actually sent to the
                     syslog daemon over /dev/log UNIX domain socket.

              •      unix:file, use UNIX domain socket directly.  It is
                     possible to specify arbitrary message format with
                     this option.  However, rsyslogd 8.9 and older
                     versions use hard coded parser function anyway that
                     limits UNIX domain socket use.  If you want to use
                     arbitrary message format with older rsyslogd
                     versions, then use UDP socket to localhost IP
                     address instead.

              •      udp:ip:port, use UDP socket.  With this method it
                     is possible to use arbitrary message format also
                     with older rsyslogd.  When sending syslog messages
                     over UDP socket extra precaution needs to be taken
                     into account, for example, syslog daemon needs to
                     be configured to listen on the specified UDP port,
                     accidental iptables rules could be interfering with
                     local syslog traffic and there are some security
                     considerations that apply to UDP sockets, but do
                     not apply to UNIX domain sockets.

              •      null, discards all messages logged to syslog.

              The default is taken from the OVS_SYSLOG_METHOD
              environment variable; if it is unset, the default is libc.

       --color[=when]
              Colorize the output (for some commands); when can be
              never, always, or auto (the default).

              Only some commands support output coloring.  Color names
              and default colors may change in future releases.

              The environment variable OVS_COLORS can be used to specify
              user-defined colors and other attributes used to highlight
              various parts of the output. If set, its value is a colon-
              separated list of capabilities that defaults to
              ac:01;31:dr=34:le=31:pm=36:pr=35:sp=33:vl=32. Supported
              capabilities were initially designed for coloring flows
              from ovs-ofctl dump-flows switch command, and they are as
              follows.

                     ac=01;31
                            SGR substring for actions= keyword in a
                            flow.  The default is a bold red text
                            foreground.

                     dr=34  SGR substring for drop keyword.  The default
                            is a dark blue text foreground.

                     le=31  SGR substring for learn= keyword in a flow.
                            The default is a red text foreground.

                     pm=36  SGR substring for flow match attribute
                            names.  The default is a cyan text
                            foreground.

                     pr=35  SGR substring for keywords in a flow that
                            are followed by arguments inside
                            parenthesis.  The default is a magenta text
                            foreground.

                     sp=33  SGR substring for some special keywords in a
                            flow, notably: table=, priority=, load:,
                            output:, move:, group:, CONTROLLER:,
                            set_field:, resubmit:, exit.  The default is
                            a yellow text foreground.

                     vl=32  SGR substring for a lone flow match
                            attribute with no field name.  The default
                            is a green text foreground.

              See the Select Graphic Rendition (SGR) section in the
              documentation of the text terminal that is used for
              permitted values and their meaning as character
              attributes.

       -h
       --help Prints a brief help message to the console.

       -V
       --version
              Prints version information to the console.

RUNTIME MANAGEMENT COMMANDS         top

       ovs-appctl(8) can send commands to a running ovs-ofctl process.
       The supported commands are listed below.

       exit   Causes ovs-ofctl to gracefully terminate.  This command
              applies only when executing the monitor or snoop commands.

       ofctl/set-output-file file
              Causes all subsequent output to go to file instead of
              stderr.  This command applies only when executing the
              monitor or snoop commands.

       ofctl/send ofmsg...
              Sends each ofmsg, specified as a sequence of hex digits
              that express an OpenFlow message, on the OpenFlow
              connection.  This command is useful only when executing
              the monitor command.

       ofctl/packet-out packet-out
              Sends an OpenFlow PACKET_OUT message specified in
              Packet-Out Syntax, on the OpenFlow connection.  See
              Packet-Out Syntax section for more information.  This
              command is useful only when executing the monitor command.

       ofctl/barrier
              Sends an OpenFlow barrier request on the OpenFlow
              connection and waits for a reply.  This command is useful
              only for the monitor command.

EXAMPLES         top

       The following examples assume that ovs-vswitchd has a bridge
       named br0 configured.

       ovs-ofctl dump-tables br0
              Prints out the switch's table stats.  (This is more
              interesting after some traffic has passed through.)

       ovs-ofctl dump-flows br0
              Prints the flow entries in the switch.

       ovs-ofctl add-flow table=0 actions=learn(table=1,hard_timeout=10,
       NXM_OF_VLAN_TCI[0..11],output:NXM_OF_IN_PORT[]), resubmit(,1)
              ovs-ofctl add-flow  table=1 priority=0 actions=flood
              Implements a level 2 MAC learning switch using the learn.

       ovs-ofctl add-flow br0 'table=0,priority=0
       actions=load:3->NXM_NX_REG0[0..15],learn(table=0,priority=1,idle_timeout=10,NXM_OF_ETH_SRC[],NXM_OF_VLAN_TCI[0..11],output:NXM_NX_REG0[0..15]),output:2
              In this use of a learn action, the first packet from each
              source MAC will be sent to port 2. Subsequent packets will
              be output to port 3, with an idle timeout of 10 seconds.
              NXM field names and match field names are both accepted,
              e.g. NXM_NX_REG0 or reg0 for the first register, and empty
              brackets may be omitted.

              Additional examples may be found documented as part of
              related sections.

SEE ALSO         top

       ovs-fields(7), ovs-actions(7), ovs-appctl(8), ovs-vswitchd(8),
       ovs-vswitchd.conf.db(8)

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 2020-12-18.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2020-12-16.)  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                     2.14.90                    ovs-ofctl(8)

Pages that refer to this page: ovs-actions(7)ovs-fields(7)ovs-dpctl(8)ovs-l3ping(8)ovs-testcontroller(8)ovs-vswitchd(8)