|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
ovn-sb(5) Open vSwitch Manual ovn-sb(5)
ovn-sb - OVN_Southbound database schema
This database holds logical and physical configuration and state
for the Open Virtual Network (OVN) system to support virtual
network abstraction. For an introduction to OVN, please see
ovn-architecture(7).
The OVN Southbound database sits at the center of the OVN
architecture. It is the one component that speaks both southbound
directly to all the hypervisors and gateways, via
ovn-controller/ovn-controller-vtep, and northbound to the Cloud
Management System, via ovn-northd:
Database Structure
The OVN Southbound database contains classes of data with
different properties, as described in the sections below.
Physical network
Physical network tables contain information about the chassis
nodes in the system. This contains all the information necessary
to wire the overlay, such as IP addresses, supported tunnel
types, and security keys.
The amount of physical network data is small (O(n) in the number
of chassis) and it changes infrequently, so it can be replicated
to every chassis.
The Chassis and Encap tables are the physical network tables.
Logical Network
Logical network tables contain the topology of logical switches
and routers, ACLs, firewall rules, and everything needed to
describe how packets traverse a logical network, represented as
logical datapath flows (see Logical Datapath Flows, below).
Logical network data may be large (O(n) in the number of logical
ports, ACL rules, etc.). Thus, to improve scaling, each chassis
should receive only data related to logical networks in which
that chassis participates.
The logical network data is ultimately controlled by the cloud
management system (CMS) running northbound of OVN. That CMS
determines the entire OVN logical configuration and therefore the
logical network data at any given time is a deterministic
function of the CMS’s configuration, although that happens
indirectly via the OVN_Northbound database and ovn-northd.
Logical network data is likely to change more quickly than
physical network data. This is especially true in a container
environment where containers are created and destroyed (and
therefore added to and deleted from logical switches) quickly.
The Logical_Flow, Multicast_Group, Address_Group, DHCP_Options,
DHCPv6_Options, and DNS tables contain logical network data.
Logical-physical bindings
These tables link logical and physical components. They show the
current placement of logical components (such as VMs and VIFs)
onto chassis, and map logical entities to the values that
represent them in tunnel encapsulations.
These tables change frequently, at least every time a VM powers
up or down or migrates, and especially quickly in a container
environment. The amount of data per VM (or VIF) is small.
Each chassis is authoritative about the VMs and VIFs that it
hosts at any given time and can efficiently flood that state to a
central location, so the consistency needs are minimal.
The Port_Binding and Datapath_Binding tables contain binding
data.
MAC bindings
The MAC_Binding table tracks the bindings from IP addresses to
Ethernet addresses that are dynamically discovered using ARP (for
IPv4) and neighbor discovery (for IPv6). Usually, IP-to-MAC
bindings for virtual machines are statically populated into the
Port_Binding table, so MAC_Binding is primarily used to discover
bindings on physical networks.
Common Columns
Some tables contain a special column named external_ids. This
column has the same form and purpose each place that it appears,
so we describe it here to save space later.
external_ids: map of string-string pairs
Key-value pairs for use by the software that
manages the OVN Southbound database rather than by
ovn-controller/ovn-controller-vtep. In particular,
ovn-northd can use key-value pairs in this column
to relate entities in the southbound database to
higher-level entities (such as entities in the OVN
Northbound database). Individual key-value pairs in
this column may be documented in some cases to aid
in understanding and troubleshooting, but the
reader should not mistake such documentation as
comprehensive.
The following list summarizes the purpose of each of the tables
in the OVN_Southbound database. Each table is described in more
detail on a later page.
Table Purpose
SB_Global Southbound configuration
Chassis Physical Network Hypervisor and Gateway Information
Chassis_Private
Chassis Private
Encap Encapsulation Types
Address_Set
Address Sets
Port_Group
Port Groups
Logical_Flow
Logical Network Flows
Logical_DP_Group
Logical Datapath Groups
Multicast_Group
Logical Port Multicast Groups
Mirror Mirror Entry
Meter Meter entry
Meter_Band
Band for meter entries
Datapath_Binding
Physical-Logical Datapath Bindings
Port_Binding
Physical-Logical Port Bindings
MAC_Binding
IP to MAC bindings
DHCP_Options
DHCP Options supported by native OVN DHCP
DHCPv6_Options
DHCPv6 Options supported by native OVN DHCPv6
Connection
OVSDB client connections.
SSL SSL configuration.
DNS Native DNS resolution
RBAC_Role RBAC_Role configuration.
RBAC_Permission
RBAC_Permission configuration.
Gateway_Chassis
Gateway_Chassis configuration.
HA_Chassis
HA_Chassis configuration.
HA_Chassis_Group
HA_Chassis_Group configuration.
Controller_Event
Controller Event table
IP_Multicast
IP_Multicast configuration.
IGMP_Group
IGMP_Group configuration.
Service_Monitor
Service_Monitor configuration.
Load_Balancer
Load_Balancer configuration.
BFD BFD configuration.
FDB Port to MAC bindings
Static_MAC_Binding
IP to MAC bindings
Chassis_Template_Var
Chassis_Template_Var configuration.
Southbound configuration for an OVN system. This table must have
exactly one row.
Summary:
Status:
nb_cfg integer
Common Columns:
external_ids map of string-string pairs
options map of string-string pairs
Common options:
options map of string-string pairs
Options for configuring BFD:
options : bfd-min-rx optional string
options : bfd-decay-min-rx
optional string
options : bfd-min-tx optional string
options : bfd-mult optional string
options : debug_drop_domain_id
optional string
options : debug_drop_collector_set
optional string
Options for configuring Load Balancers:
options : lb_hairpin_use_ct_mark
optional string
Options for configuring ovn-sbctl:
options : sbctl_probe_interval
optional string
Connection Options:
connections set of Connections
ssl optional SSL
Security Configurations:
ipsec boolean
Details:
Status:
This column allow a client to track the overall configuration
state of the system.
nb_cfg: integer
Sequence number for the configuration. When a CMS or
ovn-nbctl updates the northbound database, it increments
the nb_cfg column in the NB_Global table in the northbound
database. In turn, when ovn-northd updates the southbound
database to bring it up to date with these changes, it
updates this column to the same value.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
options: map of string-string pairs
Common options:
options: map of string-string pairs
This column provides general key/value settings. The
supported options are described individually below.
Options for configuring BFD:
These options apply when ovn-controller configures BFD on tunnels
interfaces.
options : bfd-min-rx: optional string
BFD option min-rx value to use when configuring BFD on
tunnel interfaces.
options : bfd-decay-min-rx: optional string
BFD option decay-min-rx value to use when configuring BFD
on tunnel interfaces.
options : bfd-min-tx: optional string
BFD option min-tx value to use when configuring BFD on
tunnel interfaces.
options : bfd-mult: optional string
BFD option mult value to use when configuring BFD on
tunnel interfaces.
options : debug_drop_domain_id: optional string
If set to a 8-bit number and if debug_drop_collector_set
is also configured, ovn-controller will add a sample
action to every flow that does not come from a logical
flow that contains a ’drop’ action. The 8 most significant
bits of the observation_domain_id field will be those
specified in the debug_drop_domain_id. The 24 least
significant bits of the observation_domain_id field will
be zero.
The observation_point_id will be set to the OpenFlow table
number.
options : debug_drop_collector_set: optional string
If set to a 32-bit number ovn-controller will add a sample
action to every flow that does not come from a logical
flow that contains a ’drop’ action. The sample action will
have the specified collector_set_id. The value must match
that of the local OVS configuration as described in
ovs-actions(7).
Options for configuring Load Balancers:
These options apply when ovn-controller configures load balancer
related flows.
options : lb_hairpin_use_ct_mark: optional string
By default this option is turned on (even if not present
in the database) unless its value is explicitly set to
false. This value is automatically set to false by
ovn-northd when action ct_lb_mark cannot be used for new
load balancer sessions and action ct_lb will be used
instead. ovn-controller then knows that it should check
ct_label.natted to detect load balanced traffic.
Options for configuring ovn-sbctl:
These options apply when ovn-sbctl connects to OVN Southbound
database.
options : sbctl_probe_interval: optional string
The inactivity probe interval of the connection to the OVN
Southbound database from ovn-sbctl utility, in
milliseconds. If the value is zero, it disables the
connection keepalive feature.
If the value is nonzero, then it will be forced to a value
of at least 1000 ms.
If the value is less than zero, then the default
inactivity probe interval for ovn-sbctl would be left
intact (120000 ms).
Connection Options:
connections: set of Connections
Database clients to which the Open vSwitch database server
should connect or on which it should listen, along with
options for how these connections should be configured.
See the Connection table for more information.
ssl: optional SSL
Global SSL configuration.
Security Configurations:
ipsec: boolean
Tunnel encryption configuration. If this column is set to
be true, all OVN tunnels will be encrypted with IPsec.
Each row in this table represents a hypervisor or gateway (a
chassis) in the physical network. Each chassis, via
ovn-controller/ovn-controller-vtep, adds and updates its own row,
and keeps a copy of the remaining rows to determine how to reach
other hypervisors.
When a chassis shuts down gracefully, it should remove its own
row. (This is not critical because resources hosted on the
chassis are equally unreachable regardless of whether the row is
present.) If a chassis shuts down permanently without removing
its row, some kind of manual or automatic cleanup is eventually
needed; we can devise a process for that as necessary.
Summary:
name string (must be unique within
table)
hostname string
nb_cfg integer
other_config : ovn-bridge-mappings
optional string
other_config : datapath-type optional string
other_config : iface-types optional string
other_config : ovn-cms-options
optional string
other_config : is-interconn optional string
other_config : is-remote optional string
transport_zones set of strings
other_config : ovn-chassis-mac-mappings
optional string
other_config : port-up-notif optional string
Common Columns:
external_ids map of string-string pairs
Encapsulation Configuration:
encaps set of 1 or more Encaps
Gateway Configuration:
vtep_logical_switches set of strings
Details:
name: string (must be unique within table)
OVN does not prescribe a particular format for chassis
names. ovn-controller populates this column using
external_ids:system-id in the Open_vSwitch database’s
Open_vSwitch table. ovn-controller-vtep populates this
column with name in the hardware_vtep database’s
Physical_Switch table.
hostname: string
The hostname of the chassis, if applicable. ovn-controller
will populate this column with the hostname of the host it
is running on. ovn-controller-vtep will leave this column
empty.
nb_cfg: integer
Deprecated. This column is replaced by the nb_cfg column
of the Chassis_Private table.
other_config : ovn-bridge-mappings: optional string
ovn-controller populates this key with the set of bridge
mappings it has been configured to use. Other applications
should treat this key as read-only. See ovn-controller(8)
for more information.
other_config : datapath-type: optional string
ovn-controller populates this key with the datapath type
configured in the datapath_type column of the Open_vSwitch
database’s Bridge table. Other applications should treat
this key as read-only. See ovn-controller(8) for more
information.
other_config : iface-types: optional string
ovn-controller populates this key with the interface types
configured in the iface_types column of the Open_vSwitch
database’s Open_vSwitch table. Other applications should
treat this key as read-only. See ovn-controller(8) for
more information.
other_config : ovn-cms-options: optional string
ovn-controller populates this key with the set of options
configured in the external_ids:ovn-cms-options column of
the Open_vSwitch database’s Open_vSwitch table. See
ovn-controller(8) for more information.
other_config : is-interconn: optional string
ovn-controller populates this key with the setting
configured in the external_ids:ovn-is-interconn column of
the Open_vSwitch database’s Open_vSwitch table. If set to
true, the chassis is used as an interconnection gateway.
See ovn-controller(8) for more information.
other_config : is-remote: optional string
ovn-ic set this key to true for remote interconnection
gateway chassises learned from the interconnection
southbound database. See ovn-ic(8) for more information.
transport_zones: set of strings
ovn-controller populates this key with the transport zones
configured in the external_ids:ovn-transport-zones column
of the Open_vSwitch database’s Open_vSwitch table. See
ovn-controller(8) for more information.
other_config : ovn-chassis-mac-mappings: optional string
ovn-controller populates this key with the set of options
configured in the external_ids:ovn-chassis-mac-mappings
column of the Open_vSwitch database’s Open_vSwitch table.
See ovn-controller(8) for more information.
other_config : port-up-notif: optional string
ovn-controller populates this key with true when it
supports Port_Binding.up.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
Encapsulation Configuration:
OVN uses encapsulation to transmit logical dataplane packets
between chassis.
encaps: set of 1 or more Encaps
Points to supported encapsulation configurations to
transmit logical dataplane packets to this chassis. Each
entry is a Encap record that describes the configuration.
Gateway Configuration:
A gateway is a chassis that forwards traffic between the OVN-
managed part of a logical network and a physical VLAN, extending
a tunnel-based logical network into a physical network. Gateways
are typically dedicated nodes that do not host VMs and will be
controlled by ovn-controller-vtep.
vtep_logical_switches: set of strings
Stores all VTEP logical switch names connected by this
gateway chassis. The Port_Binding table entry with
options:vtep-physical-switch equal Chassis name, and
options:vtep-logical-switch value in Chassis
vtep_logical_switches, will be associated with this
Chassis.
Each row in this table maintains per chassis private data that
are accessed only by the owning chassis (write only) and ovn-
northd, not by any other chassis. These data are stored in this
separate table instead of the Chassis table for performance
considerations: the rows in this table can be conditionally
monitored by chassises so that each chassis only get update
notifications for its own row, to avoid unnecessary chassis
private data update flooding in a large scale deployment.
Summary:
name string (must be unique within
table)
chassis optional weak reference to Chassis
nb_cfg integer
nb_cfg_timestamp integer
Common Columns:
external_ids map of string-string pairs
Details:
name: string (must be unique within table)
The name of the chassis that owns these chassis-private
data.
chassis: optional weak reference to Chassis
The reference to Chassis table for the chassis that owns
these chassis-private data.
nb_cfg: integer
Sequence number for the configuration. When ovn-controller
updates the configuration of a chassis from the contents
of the southbound database, it copies nb_cfg from the
SB_Global table into this column.
nb_cfg_timestamp: integer
The timestamp when ovn-controller finishes processing the
change corresponding to nb_cfg.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
The encaps column in the Chassis table refers to rows in this
table to identify how OVN may transmit logical dataplane packets
to this chassis. Each chassis, via ovn-controller(8) or
ovn-controller-vtep(8), adds and updates its own rows and keeps a
copy of the remaining rows to determine how to reach other
chassis.
Summary:
type string, one of geneve, stt, or
vxlan
options map of string-string pairs
options : csum optional string, either true or
false
options : dst_port optional string, containing an
integer
ip string
chassis_name string
Details:
type: string, one of geneve, stt, or vxlan
The encapsulation to use to transmit packets to this
chassis. Hypervisors and gateways must use one of: geneve,
vxlan, or stt.
options: map of string-string pairs
Options for configuring the encapsulation, which may be
type specific.
options : csum: optional string, either true or false
csum indicates whether this chassis can transmit and
receive packets that include checksums with reasonable
performance. It hints to senders transmitting data to this
chassis that they should use checksums to protect OVN
metadata. ovn-controller populates this key with the value
defined in external_ids:ovn-encap-csum column of the
Open_vSwitch database’s Open_vSwitch table. Other
applications should treat this key as read-only. See
ovn-controller(8) for more information.
In terms of performance, checksumming actually
significantly increases throughput in most common cases
when running on Linux based hosts without NICs supporting
encapsulation hardware offload (around 60% for bulk
traffic). The reason is that generally all NICs are
capable of offloading transmitted and received TCP/UDP
checksums (viewed as ordinary data packets and not as
tunnels). The benefit comes on the receive side where the
validated outer checksum can be used to additionally
validate an inner checksum (such as TCP), which in turn
allows aggregation of packets to be more efficiently
handled by the rest of the stack.
Not all devices see such a benefit. The most notable
exception is hardware VTEPs. These devices are designed to
not buffer entire packets in their switching engines and
are therefore unable to efficiently compute or validate
full packet checksums. In addition certain versions of the
Linux kernel are not able to fully take advantage of
encapsulation NIC offloads in the presence of checksums.
(This is actually a pretty narrow corner case though:
earlier versions of Linux don’t support encapsulation
offloads at all and later versions support both offloads
and checksums well.)
csum defaults to false for hardware VTEPs and true for all
other cases.
This option applies to geneve and vxlan encapsulations.
options : dst_port: optional string, containing an integer
If set, overrides the UDP (for geneve and vxlan) or TCP
(for stt) destination port.
ip: string
The IPv4 address of the encapsulation tunnel endpoint.
chassis_name: string
The name of the chassis that created this encap.
This table contains address sets synced from the Address_Set
table in the OVN_Northbound database and address sets generated
from the Port_Group table in the OVN_Northbound database.
See the documentation for the Address_Set table and Port_Group
table in the OVN_Northbound database for details.
Summary:
name string (must be unique within
table)
addresses set of strings
Details:
name: string (must be unique within table)
addresses: set of strings
This table contains names for the logical switch ports in the
OVN_Northbound database that belongs to the same group that is
defined in Port_Group in the OVN_Northbound database.
Summary:
name string (must be unique within
table)
ports set of strings
Details:
name: string (must be unique within table)
ports: set of strings
Each row in this table represents one logical flow. ovn-northd
populates this table with logical flows that implement the L2 and
L3 topologies specified in the OVN_Northbound database. Each
hypervisor, via ovn-controller, translates the logical flows into
OpenFlow flows specific to its hypervisor and installs them into
Open vSwitch.
Logical flows are expressed in an OVN-specific format, described
here. A logical datapath flow is much like an OpenFlow flow,
except that the flows are written in terms of logical ports and
logical datapaths instead of physical ports and physical
datapaths. Translation between logical and physical flows helps
to ensure isolation between logical datapaths. (The logical flow
abstraction also allows the OVN centralized components to do less
work, since they do not have to separately compute and push out
physical flows to each chassis.)
The default action when no flow matches is to drop packets.
Architectural Logical Life Cycle of a Packet
This following description focuses on the life cycle of a packet
through a logical datapath, ignoring physical details of the
implementation. Please refer to Architectural Physical Life Cycle
of a Packet in ovn-architecture(7) for the physical information.
The description here is written as if OVN itself executes these
steps, but in fact OVN (that is, ovn-controller) programs Open
vSwitch, via OpenFlow and OVSDB, to execute them on its behalf.
At a high level, OVN passes each packet through the logical
datapath’s logical ingress pipeline, which may output the packet
to one or more logical port or logical multicast groups. For each
such logical output port, OVN passes the packet through the
datapath’s logical egress pipeline, which may either drop the
packet or deliver it to the destination. Between the two
pipelines, outputs to logical multicast groups are expanded into
logical ports, so that the egress pipeline only processes a
single logical output port at a time. Between the two pipelines
is also where, when necessary, OVN encapsulates a packet in a
tunnel (or tunnels) to transmit to remote hypervisors.
In more detail, to start, OVN searches the Logical_Flow table for
a row with correct logical_datapath or a logical_dp_group, a
pipeline of ingress, a table_id of 0, and a match that is true
for the packet. If none is found, OVN drops the packet. If OVN
finds more than one, it chooses the match with the highest
priority. Then OVN executes each of the actions specified in the
row’s actions column, in the order specified. Some actions, such
as those to modify packet headers, require no further details.
The next and output actions are special.
The next action causes the above process to be repeated
recursively, except that OVN searches for table_id of 1 instead
of 0. Similarly, any next action in a row found in that table
would cause a further search for a table_id of 2, and so on. When
recursive processing completes, flow control returns to the
action following next.
The output action also introduces recursion. Its effect depends
on the current value of the outport field. Suppose outport
designates a logical port. First, OVN compares inport to outport;
if they are equal, it treats the output as a no-op by default. In
the common case, where they are different, the packet enters the
egress pipeline. This transition to the egress pipeline discards
register data, e.g. reg0 ... reg9 and connection tracking state,
to achieve uniform behavior regardless of whether the egress
pipeline is on a different hypervisor (because registers aren’t
preserve across tunnel encapsulation).
To execute the egress pipeline, OVN again searches the
Logical_Flow table for a row with correct logical_datapath or a
logical_dp_group, a table_id of 0, a match that is true for the
packet, but now looking for a pipeline of egress. If no matching
row is found, the output becomes a no-op. Otherwise, OVN executes
the actions for the matching flow (which is chosen from multiple,
if necessary, as already described).
In the egress pipeline, the next action acts as already
described, except that it, of course, searches for egress flows.
The output action, however, now directly outputs the packet to
the output port (which is now fixed, because outport is read-only
within the egress pipeline).
The description earlier assumed that outport referred to a
logical port. If it instead designates a logical multicast group,
then the description above still applies, with the addition of
fan-out from the logical multicast group to each logical port in
the group. For each member of the group, OVN executes the logical
pipeline as described, with the logical output port replaced by
the group member.
Pipeline Stages
ovn-northd populates the Logical_Flow table with the logical
flows described in detail in ovn-northd(8).
Summary:
logical_datapath optional Datapath_Binding
logical_dp_group optional Logical_DP_Group
pipeline string, either egress or ingress
table_id integer, in range 0 to 32
priority integer, in range 0 to 65,535
match string
actions string
tags map of string-string pairs
controller_meter optional string
external_ids : stage-name optional string
external_ids : stage-hint optional string, containing an uuid
external_ids : source optional string
Common Columns:
external_ids map of string-string pairs
Details:
logical_datapath: optional Datapath_Binding
The logical datapath to which the logical flow belongs.
logical_dp_group: optional Logical_DP_Group
The group of logical datapaths to which the logical flow
belongs. This means that the same logical flow belongs to
all datapaths in a group.
pipeline: string, either egress or ingress
The primary flows used for deciding on a packet’s
destination are the ingress flows. The egress flows
implement ACLs. See Logical Life Cycle of a Packet, above,
for details.
table_id: integer, in range 0 to 32
The stage in the logical pipeline, analogous to an
OpenFlow table number.
priority: integer, in range 0 to 65,535
The flow’s priority. Flows with numerically higher
priority take precedence over those with lower. If two
logical datapath flows with the same priority both match,
then the one actually applied to the packet is undefined.
match: string
A matching expression. OVN provides a superset of OpenFlow
matching capabilities, using a syntax similar to Boolean
expressions in a programming language.
The most important components of match expression are
comparisons between symbols and constants, e.g. ip4.dst ==
192.168.0.1, ip.proto == 6, arp.op == 1, eth.type ==
0x800. The logical AND operator && and logical OR operator
|| can combine comparisons into a larger expression.
Matching expressions also support parentheses for
grouping, the logical NOT prefix operator !, and literals
0 and 1 to express ``false’’ or ``true,’’ respectively.
The latter is useful by itself as a catch-all expression
that matches every packet.
Match expressions also support a kind of function syntax.
The following functions are supported:
is_chassis_resident(lport)
Evaluates to true on a chassis on which logical
port lport (a quoted string) resides, and to false
elsewhere. This function was introduced in OVN 2.7.
Symbols
Type. Symbols have integer or string type. Integer symbols
have a width in bits.
Kinds. There are three kinds of symbols:
• Fields. A field symbol represents a packet header
or metadata field. For example, a field named
vlan.tci might represent the VLAN TCI field in a
packet.
A field symbol can have integer or string type.
Integer fields can be nominal or ordinal (see Level
of Measurement, below).
• Subfields. A subfield represents a subset of bits
from a larger field. For example, a field vlan.vid
might be defined as an alias for vlan.tci[0..11].
Subfields are provided for syntactic convenience,
because it is always possible to instead refer to a
subset of bits from a field directly.
Only ordinal fields (see Level of Measurement,
below) may have subfields. Subfields are always
ordinal.
• Predicates. A predicate is shorthand for a Boolean
expression. Predicates may be used much like 1-bit
fields. For example, ip4 might expand to eth.type
== 0x800. Predicates are provided for syntactic
convenience, because it is always possible to
instead specify the underlying expression directly.
A predicate whose expansion refers to any nominal
field or predicate (see Level of Measurement,
below) is nominal; other predicates have Boolean
level of measurement.
Level of Measurement. See
http://en.wikipedia.org/wiki/Level_of_measurement for the
statistical concept on which this classification is based.
There are three levels:
• Ordinal. In statistics, ordinal values can be
ordered on a scale. OVN considers a field (or
subfield) to be ordinal if its bits can be examined
individually. This is true for the OpenFlow fields
that OpenFlow or Open vSwitch makes ``maskable.’’
Any use of a ordinal field may specify a single bit
or a range of bits, e.g. vlan.tci[13..15] refers to
the PCP field within the VLAN TCI, and eth.dst[40]
refers to the multicast bit in the Ethernet
destination address.
OVN supports all the usual arithmetic relations
(==, !=, <, <=, >, and >=) on ordinal fields and
their subfields, because OVN can implement these in
OpenFlow and Open vSwitch as collections of bitwise
tests.
• Nominal. In statistics, nominal values cannot be
usefully compared except for equality. This is true
of OpenFlow port numbers, Ethernet types, and IP
protocols are examples: all of these are just
identifiers assigned arbitrarily with no deeper
meaning. In OpenFlow and Open vSwitch, bits in
these fields generally aren’t individually
addressable.
OVN only supports arithmetic tests for equality on
nominal fields, because OpenFlow and Open vSwitch
provide no way for a flow to efficiently implement
other comparisons on them. (A test for inequality
can be sort of built out of two flows with
different priorities, but OVN matching expressions
always generate flows with a single priority.)
String fields are always nominal.
• Boolean. A nominal field that has only two values,
0 and 1, is somewhat exceptional, since it is easy
to support both equality and inequality tests on
such a field: either one can be implemented as a
test for 0 or 1.
Only predicates (see above) have a Boolean level of
measurement.
This isn’t a standard level of measurement.
Prerequisites. Any symbol can have prerequisites, which
are additional condition implied by the use of the symbol.
For example, For example, icmp4.type symbol might have
prerequisite icmp4, which would cause an expression
icmp4.type == 0 to be interpreted as icmp4.type == 0 &&
icmp4, which would in turn expand to icmp4.type == 0 &&
eth.type == 0x800 && ip4.proto == 1 (assuming icmp4 is a
predicate defined as suggested under Types above).
Relational operators
All of the standard relational operators ==, !=, <, <=, >,
and >= are supported. Nominal fields support only == and
!=, and only in a positive sense when outer ! are taken
into account, e.g. given string field inport, inport ==
"eth0" and !(inport != "eth0") are acceptable, but not
inport != "eth0".
The implementation of == (or != when it is negated), is
more efficient than that of the other relational
operators.
Constants
Integer constants may be expressed in decimal, hexadecimal
prefixed by 0x, or as dotted-quad IPv4 addresses, IPv6
addresses in their standard forms, or Ethernet addresses
as colon-separated hex digits. A constant in any of these
forms may be followed by a slash and a second constant
(the mask) in the same form, to form a masked constant.
IPv4 and IPv6 masks may be given as integers, to express
CIDR prefixes.
String constants have the same syntax as quoted strings in
JSON (thus, they are Unicode strings).
Some operators support sets of constants written inside
curly braces { ... }. Commas between elements of a set,
and after the last elements, are optional. With ==,
``field == { constant1, constant2, ... }’’ is syntactic
sugar for ``field == constant1 || field == constant2 ||
.... Similarly, ``field != { constant1, constant2, ... }’’
is equivalent to ``field != constant1 && field !=
constant2 && ...’’.
You may refer to a set of IPv4, IPv6, or MAC addresses
stored in the Address_Set table by its name. An
Address_Set with a name of set1 can be referred to as
$set1.
You may refer to a group of logical switch ports stored in
the Port_Group table by its name. An Port_Group with a
name of port_group1 can be referred to as @port_group1.
Additionally, you may refer to the set of addresses
belonging to a group of logical switch ports stored in the
Port_Group table by its name followed by a suffix
’_ip4’/’_ip6’. The IPv4 address set of a Port_Group with a
name of port_group1 can be referred to as
$port_group1_ip4, and the IPv6 address set of the same
Port_Group can be referred to as $port_group1_ip6
Miscellaneous
Comparisons may name the symbol or the constant first,
e.g. tcp.src == 80 and 80 == tcp.src are both acceptable.
Tests for a range may be expressed using a syntax like
1024 <= tcp.src <= 49151, which is equivalent to 1024 <=
tcp.src && tcp.src <= 49151.
For a one-bit field or predicate, a mention of its name is
equivalent to symobl == 1, e.g. vlan.present is equivalent
to vlan.present == 1. The same is true for one-bit
subfields, e.g. vlan.tci[12]. There is no technical
limitation to implementing the same for ordinal fields of
all widths, but the implementation is expensive enough
that the syntax parser requires writing an explicit
comparison against zero to make mistakes less likely, e.g.
in tcp.src != 0 the comparison against 0 is required.
Operator precedence is as shown below, from highest to
lowest. There are two exceptions where parentheses are
required even though the table would suggest that they are
not: && and || require parentheses when used together, and
! requires parentheses when applied to a relational
expression. Thus, in (eth.type == 0x800 || eth.type ==
0x86dd) && ip.proto == 6 or !(arp.op == 1), the
parentheses are mandatory.
• ()
• == != < <= > >=
• !
• && ||
Comments may be introduced by //, which extends to the
next new-line. Comments within a line may be bracketed by
/* and */. Multiline comments are not supported.
Symbols
Most of the symbols below have integer type. Only inport
and outport have string type. inport names a logical port.
Thus, its value is a logical_port name from the
Port_Binding table. outport may name a logical port, as
inport, or a logical multicast group defined in the
Multicast_Group table. For both symbols, only names within
the flow’s logical datapath may be used.
The regX symbols are 32-bit integers. The xxregX symbols
are 128-bit integers, which overlay four of the 32-bit
registers: xxreg0 overlays reg0 through reg3, with reg0
supplying the most-significant bits of xxreg0 and reg3 the
least-significant. xxreg1 similarly overlays reg4 through
reg7.
• reg0...reg9
• xxreg0 xxreg1
• inport outport
• flags.loopback
• pkt.mark
• eth.src eth.dst eth.type
• vlan.tci vlan.vid vlan.pcp vlan.present
• ip.proto ip.dscp ip.ecn ip.ttl ip.frag
• ip4.src ip4.dst
• ip6.src ip6.dst ip6.label
• arp.op arp.spa arp.tpa arp.sha arp.tha
• rarp.op rarp.spa rarp.tpa rarp.sha rarp.tha
• tcp.src tcp.dst tcp.flags
• udp.src udp.dst
• sctp.src sctp.dst
• icmp4.type icmp4.code
• icmp6.type icmp6.code
• nd.target nd.sll nd.tll
• ct_mark ct_label
• ct_state, which has several Boolean subfields. The
ct_next action initializes the following subfields:
• ct.trk: Always set to true by ct_next to
indicate that connection tracking has taken
place. All other ct subfields have ct.trk as
a prerequisite.
• ct.new: True for a new flow
• ct.est: True for an established flow
• ct.rel: True for a related flow
• ct.rpl: True for a reply flow
• ct.inv: True for a connection entry in a bad
state
The ct_dnat, ct_snat, and ct_lb actions initialize
the following subfields:
• ct.dnat: True for a packet whose destination
IP address has been changed.
• ct.snat: True for a packet whose source IP
address has been changed.
The following predicates are supported:
• eth.bcast expands to eth.dst == ff:ff:ff:ff:ff:ff
• eth.mcast expands to eth.dst[40]
• vlan.present expands to vlan.tci[12]
• ip4 expands to eth.type == 0x800
• ip4.src_mcast expands to ip4.src[28..31] == 0xe
• ip4.mcast expands to ip4.dst[28..31] == 0xe
• ip6 expands to eth.type == 0x86dd
• ip expands to ip4 || ip6
• icmp4 expands to ip4 && ip.proto == 1
• icmp6 expands to ip6 && ip.proto == 58
• icmp expands to icmp4 || icmp6
• ip.is_frag expands to ip.frag[0]
• ip.later_frag expands to ip.frag[1]
• ip.first_frag expands to ip.is_frag &&
!ip.later_frag
• arp expands to eth.type == 0x806
• rarp expands to eth.type == 0x8035
• nd expands to icmp6.type == {135, 136} &&
icmp6.code == 0 && ip.ttl == 255
• nd_ns expands to icmp6.type == 135 && icmp6.code ==
0 && ip.ttl == 255
• nd_na expands to icmp6.type == 136 && icmp6.code ==
0 && ip.ttl == 255
• nd_rs expands to icmp6.type == 133 && icmp6.code ==
0 && ip.ttl == 255
• nd_ra expands to icmp6.type == 134 && icmp6.code ==
0 && ip.ttl == 255
• tcp expands to ip.proto == 6
• udp expands to ip.proto == 17
• sctp expands to ip.proto == 132
actions: string
Logical datapath actions, to be executed when the logical
flow represented by this row is the highest-priority
match.
Actions share lexical syntax with the match column. An
empty set of actions (or one that contains just white
space or comments), or a set of actions that consists of
just drop;, causes the matched packets to be dropped.
Otherwise, the column should contain a sequence of
actions, each terminated by a semicolon.
The following actions are defined:
output;
In the ingress pipeline, this action executes the
egress pipeline as a subroutine. If outport names a
logical port, the egress pipeline executes once; if
it is a multicast group, the egress pipeline runs
once for each logical port in the group.
In the egress pipeline, this action performs the
actual output to the outport logical port. (In the
egress pipeline, outport never names a multicast
group.)
By default, output to the input port is implicitly
dropped, that is, output becomes a no-op if outport
== inport. Occasionally it may be useful to
override this behavior, e.g. to send an ARP reply
to an ARP request; to do so, use flags.loopback = 1
to allow the packet to "hair-pin" back to the input
port.
next;
next(table);
next(pipeline=pipeline, table=table);
Executes the given logical datapath table in pipeline
as a subroutine. The default table is just after the
current one. If pipeline is specified, it may be
ingress or egress; the default pipeline is the one
currently executing. Actions in the both ingress and
egress pipeline can use next to jump across the other
pipeline. Actions in the ingress pipeline should use
next to jump into the specific table of egress
pipeline only if it is certain that the packets are
local and not tunnelled and wants to skip certain
stages in the packet processing.
field = constant;
Sets data or metadata field field to constant value
constant, e.g. outport = "vif0"; to set the logical
output port. To set only a subset of bits in a field,
specify a subfield for field or a masked constant,
e.g. one may use vlan.pcp[2] = 1; or vlan.pcp = 4/4;
to set the most significant bit of the VLAN PCP.
Assigning to a field with prerequisites implicitly
adds those prerequisites to match; thus, for example,
a flow that sets tcp.dst applies only to TCP flows,
regardless of whether its match mentions any TCP
field.
Not all fields are modifiable (e.g. eth.type and
ip.proto are read-only), and not all modifiable
fields may be partially modified (e.g. ip.ttl must
assigned as a whole). The outport field is modifiable
in the ingress pipeline but not in the egress
pipeline.
ovn_field = constant;
Sets OVN field ovn_field to constant value constant.
OVN supports setting the values of certain fields
which are not yet supported in OpenFlow to set or
modify them.
Below are the supported OVN fields:
• icmp4.frag_mtu icmp6.frag_mtu
This field sets the low-order 16 bits of the
ICMP{4,6} header field that is labelled
"unused" in the ICMP specification as defined
in the RFC 1191 with the value specified in
constant.
Eg. icmp4.frag_mtu = 1500;
field1 = field2;
Sets data or metadata field field1 to the value of
data or metadata field field2, e.g. reg0 = ip4.src;
copies ip4.src into reg0. To modify only a subset of
a field’s bits, specify a subfield for field1 or
field2 or both, e.g. vlan.pcp = reg0[0..2]; copies
the least-significant bits of reg0 into the VLAN PCP.
field1 and field2 must be the same type, either both
string or both integer fields. If they are both
integer fields, they must have the same width.
If field1 or field2 has prerequisites, they are added
implicitly to match. It is possible to write an
assignment with contradictory prerequisites, such as
ip4.src = ip6.src[0..31];, but the contradiction
means that a logical flow with such an assignment
will never be matched.
field1 <-> field2;
Similar to field1 = field2; except that the two
values are exchanged instead of copied. Both field1
and field2 must modifiable.
push(field);
Push the value of field to the stack top.
pop(field);
Pop the stack top and store the value to field, which
must be modifiable.
ip.ttl--;
Decrements the IPv4 or IPv6 TTL. If this would make
the TTL zero or negative, then processing of the
packet halts; no further actions are processed. (To
properly handle such cases, a higher-priority flow
should match on ip.ttl == {0, 1};.)
Prerequisite: ip
ct_next;
Apply connection tracking to the flow, initializing
ct_state for matching in later tables. Automatically
moves on to the next table, as if followed by next.
As a side effect, IP fragments will be reassembled
for matching. If a fragmented packet is output, then
it will be sent with any overlapping fragments
squashed. The connection tracking state is scoped by
the logical port when the action is used in a flow
for a logical switch, so overlapping addresses may be
used. To allow traffic related to the matched flow,
execute ct_commit . Connection tracking state is
scoped by the logical topology when the action is
used in a flow for a router.
It is possible to have actions follow ct_next, but
they will not have access to any of its side-effects
and is not generally useful.
ct_commit { };
ct_commit { ct_mark=value[/mask]; };
ct_commit { ct_label=value[/mask]; };
ct_commit { ct_mark=value[/mask]; ct_label=value[/mask];
};
Commit the flow to the connection tracking entry
associated with it by a previous call to ct_next.
When ct_mark=value[/mask] and/or
ct_label=value[/mask] are supplied, ct_mark and/or
ct_label will be set to the values indicated by
value[/mask] on the connection tracking entry.
ct_mark is a 32-bit field. ct_label is a 128-bit
field. The value[/mask] should be specified in hex
string if more than 64bits are to be used. Registers
and other named fields can be used for value. ct_mark
and ct_label may be sub-addressed in order to have
specific bits set.
Note that if you want processing to continue in the
next table, you must execute the next action after
ct_commit. You may also leave out next which will
commit connection tracking state, and then drop the
packet. This could be useful for setting ct_mark on a
connection tracking entry before dropping a packet,
for example.
ct_commit_to_zone(dnat);
ct_commit_to_zone(snat);
Commit the flow to the specific zone in the
connection tracker. The packet is then automatically
sent to the next tables as if followed by next;
action. The next tables will see the changes in the
packet caused by the connection tracker.
Note that this action is meaningful only in the
Logical Router Datapath as the Logical Switch
Datapath does not use separate connection tracking
zones. Using this action in Logical Switch Datapath
falls back to committing the flow into the logical
port’s conntrack zone.
ct_dnat;
ct_dnat(IP);
ct_dnat sends the packet through the DNAT zone in
connection tracking table to unDNAT any packet that
was DNATed in the opposite direction. The packet is
then automatically sent to the next tables as if
followed by next; action. The next tables will see
the changes in the packet caused by the connection
tracker.
ct_dnat(IP) sends the packet through the DNAT zone to
change the destination IP address of the packet to
the one provided inside the parentheses and commits
the connection. The packet is then automatically sent
to the next tables as if followed by next; action.
The next tables will see the changes in the packet
caused by the connection tracker.
ct_snat;
ct_snat(IP);
ct_snat sends the packet through the SNAT zone to
unSNAT any packet that was SNATed in the opposite
direction. The packet is automatically sent to the
next tables as if followed by the next; action. The
next tables will see the changes in the packet caused
by the connection tracker.
ct_snat(IP) sends the packet through the SNAT zone to
change the source IP address of the packet to the one
provided inside the parenthesis and commits the
connection. The packet is then automatically sent to
the next tables as if followed by next; action. The
next tables will see the changes in the packet caused
by the connection tracker.
ct_dnat_in_czone;
ct_dnat_in_czone(IP);
ct_dnat_in_czone sends the packet through the common
NAT zone (used for both DNAT and SNAT) in connection
tracking table to unDNAT any packet that was DNATed
in the opposite direction. The packet is then
automatically sent to the next tables as if followed
by next; action. The next tables will see the changes
in the packet caused by the connection tracker.
ct_dnat_in_czone(IP) sends the packet through the
common NAT zone to change the destination IP address
of the packet to the one provided inside the
parentheses and commits the connection. The packet is
then automatically sent to the next tables as if
followed by next; action. The next tables will see
the changes in the packet caused by the connection
tracker.
ct_snat_in_czone;
ct_snat_in_czone(IP);
ct_snat_in_czone sends the packet through the common
NAT zone to unSNAT any packet that was SNATed in the
opposite direction. The packet is automatically sent
to the next tables as if followed by the next;
action. The next tables will see the changes in the
packet caused by the connection tracker.
ct_snat_in_czone(IP) sends the packet\ through the
common NAT zone to change the source IP address of
the packet to the one provided inside the parenthesis
and commits the connection. The packet is then
automatically sent to the next tables as if followed
by next; action. The next tables will see the changes
in the packet caused by the connection tracker.
ct_clear;
Clears connection tracking state.
ct_commit_nat;
Applies NAT and commits the connection to the CT.
Automatically moves on to the next table, as if
followed by next. This is very useful for connections
that are in related state for already existing
connections and allows the NAT to be applied to them
as well.
clone { action; ... };
Makes a copy of the packet being processed and
executes each action on the copy. Actions following
the clone action, if any, apply to the original,
unmodified packet. This can be used as a way to
``save and restore’’ the packet around a set of
actions that may modify it and should not persist.
arp { action; ... };
Temporarily replaces the IPv4 packet being processed
by an ARP packet and executes each nested action on
the ARP packet. Actions following the arp action, if
any, apply to the original, unmodified packet.
The ARP packet that this action operates on is
initialized based on the IPv4 packet being processed,
as follows. These are default values that the nested
actions will probably want to change:
• eth.src unchanged
• eth.dst unchanged
• eth.type = 0x0806
• arp.op = 1 (ARP request)
• arp.sha copied from eth.src
• arp.spa copied from ip4.src
• arp.tha = 00:00:00:00:00:00
• arp.tpa copied from ip4.dst
The ARP packet has the same VLAN header, if any, as
the IP packet it replaces.
Prerequisite: ip4
get_arp(P, A);
Parameters: logical port string field P, 32-bit IP
address field A.
Looks up A in P’s mac binding table. If an entry is
found, stores its Ethernet address in eth.dst,
otherwise stores 00:00:00:00:00:00 in eth.dst.
Example: get_arp(outport, ip4.dst);
put_arp(P, A, E);
Parameters: logical port string field P, 32-bit IP
address field A, 48-bit Ethernet address field E.
Adds or updates the entry for IP address A in logical
port P’s mac binding table, setting its Ethernet
address to E.
Example: put_arp(inport, arp.spa, arp.sha);
R = lookup_arp(P, A, M);
Parameters: logical port string field P, 32-bit IP
address field A, 48-bit MAC address field M.
Result: stored to a 1-bit subfield R.
Looks up A and M in P’s mac binding table. If an
entry is found, stores 1 in the 1-bit subfield R,
else 0.
Example: reg0[0] = lookup_arp(inport, arp.spa,
arp.sha);
R = lookup_arp_ip(P, A);
Parameters: logical port string field P, 32-bit IP
address field A.
Result: stored to a 1-bit subfield R.
Looks up A in P’s mac binding table. If an entry is
found, stores 1 in the 1-bit subfield R, else 0.
Example: reg0[0] = lookup_arp_ip(inport, arp.spa);
P = get_fdb(A);
Parameters:48-bit MAC address field A.
Looks up A in fdb table. If an entry is found, stores
the logical port key to the out parameter P.
Example: outport = get_fdb(eth.src);
put_fdb(P, A);
Parameters: logical port string field P, 48-bit MAC
address field A.
Adds or updates the entry for Ethernet address A in
fdb table, setting its logical port key to P.
Example: put_fdb(inport, arp.spa);
R = lookup_fdb(P, A);
Parameters: 48-bit MAC address field M, logical port
string field P.
Result: stored to a 1-bit subfield R.
Looks up A in fdb table. If an entry is found and the
logical port key is P, P, stores 1 in the 1-bit
subfield R, else 0. If flags.localnet is set then 1
is stored if an entry is found and the logical port
key is P or if an entry is found and the entry port
type is VIF.
Example: reg0[0] = lookup_fdb(inport, eth.src);
nd_ns { action; ... };
Temporarily replaces the IPv6 packet being processed
by an IPv6 Neighbor Solicitation packet and executes
each nested action on the IPv6 NS packet. Actions
following the nd_ns action, if any, apply to the
original, unmodified packet.
The IPv6 NS packet that this action operates on is
initialized based on the IPv6 packet being processed,
as follows. These are default values that the nested
actions will probably want to change:
• eth.src unchanged
• eth.dst set to IPv6 multicast MAC address
• eth.type = 0x86dd
• ip6.src copied from ip6.src
• ip6.dst set to IPv6 Solicited-Node multicast
address
• icmp6.type = 135 (Neighbor Solicitation)
• nd.target copied from ip6.dst
The IPv6 NS packet has the same VLAN header, if any,
as the IP packet it replaces.
Prerequisite: ip6
nd_na { action; ... };
Temporarily replaces the IPv6 neighbor solicitation
packet being processed by an IPv6 neighbor
advertisement (NA) packet and executes each nested
action on the NA packet. Actions following the nd_na
action, if any, apply to the original, unmodified
packet.
The NA packet that this action operates on is
initialized based on the IPv6 packet being processed,
as follows. These are default values that the nested
actions will probably want to change:
• eth.dst exchanged with eth.src
• eth.type = 0x86dd
• ip6.dst copied from ip6.src
• ip6.src copied from nd.target
• icmp6.type = 136 (Neighbor Advertisement)
• nd.target unchanged
• nd.sll = 00:00:00:00:00:00
• nd.tll copied from eth.dst
The ND packet has the same VLAN header, if any, as
the IPv6 packet it replaces.
Prerequisite: nd_ns
nd_na_router { action; ... };
Temporarily replaces the IPv6 neighbor solicitation
packet being processed by an IPv6 neighbor
advertisement (NA) packet, sets ND_NSO_ROUTER in the
RSO flags and executes each nested action on the NA
packet. Actions following the nd_na_router action, if
any, apply to the original, unmodified packet.
The NA packet that this action operates on is
initialized based on the IPv6 packet being processed,
as follows. These are default values that the nested
actions will probably want to change:
• eth.dst exchanged with eth.src
• eth.type = 0x86dd
• ip6.dst copied from ip6.src
• ip6.src copied from nd.target
• icmp6.type = 136 (Neighbor Advertisement)
• nd.target unchanged
• nd.sll = 00:00:00:00:00:00
• nd.tll copied from eth.dst
The ND packet has the same VLAN header, if any, as
the IPv6 packet it replaces.
Prerequisite: nd_ns
get_nd(P, A);
Parameters: logical port string field P, 128-bit IPv6
address field A.
Looks up A in P’s mac binding table. If an entry is
found, stores its Ethernet address in eth.dst,
otherwise stores 00:00:00:00:00:00 in eth.dst.
Example: get_nd(outport, ip6.dst);
put_nd(P, A, E);
Parameters: logical port string field P, 128-bit IPv6
address field A, 48-bit Ethernet address field E.
Adds or updates the entry for IPv6 address A in
logical port P’s mac binding table, setting its
Ethernet address to E.
Example: put_nd(inport, nd.target, nd.tll);
R = lookup_nd(P, A, M);
Parameters: logical port string field P, 128-bit IP
address field A, 48-bit MAC address field M.
Result: stored to a 1-bit subfield R.
Looks up A and M in P’s mac binding table. If an
entry is found, stores 1 in the 1-bit subfield R,
else 0.
Example: reg0[0] = lookup_nd(inport, ip6.src,
eth.src);
R = lookup_nd_ip(P, A);
Parameters: logical port string field P, 128-bit IP
address field A.
Result: stored to a 1-bit subfield R.
Looks up A in P’s mac binding table. If an entry is
found, stores 1 in the 1-bit subfield R, else 0.
Example: reg0[0] = lookup_nd_ip(inport, ip6.src);
R = put_dhcp_opts(D1 = V1, D2 = V2, ..., Dn = Vn);
Parameters: one or more DHCP option/value pairs,
which must include an offerip option (with code 0).
Result: stored to a 1-bit subfield R.
Valid only in the ingress pipeline.
When this action is applied to a DHCP request packet
(DHCPDISCOVER or DHCPREQUEST), it changes the packet
into a DHCP reply (DHCPOFFER or DHCPACK,
respectively), replaces the options by those
specified as parameters, and stores 1 in R.
When this action is applied to a non-DHCP packet or a
DHCP packet that is not DHCPDISCOVER or DHCPREQUEST,
it leaves the packet unchanged and stores 0 in R.
The contents of the DHCP_Option table control the
DHCP option names and values that this action
supports.
Example: reg0[0] = put_dhcp_opts(offerip = 10.0.0.2,
router = 10.0.0.1, netmask = 255.255.255.0,
dns_server = {8.8.8.8, 7.7.7.7});
R = put_dhcpv6_opts(D1 = V1, D2 = V2, ..., Dn = Vn);
Parameters: one or more DHCPv6 option/value pairs.
Result: stored to a 1-bit subfield R.
Valid only in the ingress pipeline.
When this action is applied to a DHCPv6 request
packet, it changes the packet into a DHCPv6 reply,
replaces the options by those specified as
parameters, and stores 1 in R.
When this action is applied to a non-DHCPv6 packet or
an invalid DHCPv6 request packet , it leaves the
packet unchanged and stores 0 in R.
The contents of the DHCPv6_Options table control the
DHCPv6 option names and values that this action
supports.
Example: reg0[3] = put_dhcpv6_opts(ia_addr = aef0::4,
server_id = 00:00:00:00:10:02,
dns_server={ae70::1,ae70::2});
set_queue(queue_number);
Parameters: Queue number queue_number, in the range 0
to 61440.
This is a logical equivalent of the OpenFlow
set_queue action. It affects packets that egress a
hypervisor through a physical interface. For nonzero
queue_number, it configures packet queuing to match
the settings configured for the Port_Binding with
options:qdisc_queue_id matching queue_number. When
queue_number is zero, it resets queuing to the
default strategy.
Example: set_queue(10);
ct_lb;
ct_lb(backends=ip[:port][,...][;
hash_fields=field1,field2,...][; ct_flag]);
With arguments, ct_lb commits the packet to the
connection tracking table and DNATs the packet’s
destination IP address (and port) to the IP address
or addresses (and optional ports) specified in the
backends. If multiple comma-separated IP addresses
are specified, each is given equal weight for picking
the DNAT address. By default, dp_hash is used as the
OpenFlow group selection method, but if hash_fields
is specified, hash is used as the selection method,
and the fields listed are used as the hash fields.
The ct_flag field represents one of supported flag:
skip_snat or force_snat, this flag will be stored in
ct_label register.
Without arguments, ct_lb sends the packet to the
connection tracking table to NAT the packets. If the
packet is part of an established connection that was
previously committed to the connection tracker via
ct_lb(...), it will automatically get DNATed to the
same IP address as the first packet in that
connection.
Processing automatically moves on to the next table,
as if next; were specified, and later tables act on
the packet as modified by the connection tracker.
Connection tracking state is scoped by the logical
port when the action is used in a flow for a logical
switch, so overlapping addresses may be used.
Connection tracking state is scoped by the logical
topology when the action is used in a flow for a
router.
ct_lb_mark;
ct_lb_mark(backends=ip[:port][,...][;
hash_fields=field1,field2,...][; ct_flag]);
Same as ct_lb, except that it internally uses ct_mark
to store the NAT flag, while ct_lb uses ct_label for
the same purpose.
R = dns_lookup();
Parameters: No parameters.
Result: stored to a 1-bit subfield R.
Valid only in the ingress pipeline.
When this action is applied to a valid DNS request (a
UDP packet typically directed to port 53), it
attempts to resolve the query using the contents of
the DNS table. If it is successful, it changes the
packet into a DNS reply and stores 1 in R. If the
action is applied to a non-DNS packet, an invalid DNS
request packet, or a valid DNS request for which the
DNS table does not supply an answer, it leaves the
packet unchanged and stores 0 in R.
Regardless of success, the action does not make any
of the changes to the flow that are necessary to
direct the packet back to the requester. The logical
pipeline can implement this behavior with matches and
actions in later tables.
Example: reg0[3] = dns_lookup();
Prerequisite: udp
R = put_nd_ra_opts(D1 = V1, D2 = V2, ..., Dn = Vn);
Parameters: The following IPv6 ND Router
Advertisement option/value pairs as defined in RFC
4861.
• addr_mode
Mandatory parameter which specifies the
address mode flag to be set in the RA flag
options field. The value of this option is a
string and the following values can be defined
- "slaac", "dhcpv6_stateful" and
"dhcpv6_stateless".
• slla
Mandatory parameter which specifies the link-
layer address of the interface from which the
Router Advertisement is sent.
• mtu
Optional parameter which specifies the MTU.
• prefix
Optional parameter which should be specified
if the addr_mode is "slaac" or
"dhcpv6_stateless". The value should be an
IPv6 prefix which will be used for stateless
IPv6 address configuration. This option can be
defined multiple times.
Result: stored to a 1-bit subfield R.
Valid only in the ingress pipeline.
When this action is applied to an IPv6 Router
solicitation request packet, it changes the packet
into an IPv6 Router Advertisement reply and adds the
options specified in the parameters, and stores 1 in
R.
When this action is applied to a non-IPv6 Router
solicitation packet or an invalid IPv6 request packet
, it leaves the packet unchanged and stores 0 in R.
Example: reg0[3] = put_nd_ra_opts(addr_mode =
"slaac", slla = 00:00:00:00:10:02, prefix =
aef0::/64, mtu = 1450);
set_meter(rate);
set_meter(rate, burst);
Parameters: rate limit int field rate in kbps, burst
rate limits int field burst in kbps.
This action sets the rate limit for a flow.
Example: set_meter(100, 1000);
R = check_pkt_larger(L)
Parameters: packet length L to check for in bytes.
Result: stored to a 1-bit subfield R.
This is a logical equivalent of the OpenFlow
check_pkt_larger action. If the packet is larger than
the length specified in L, it stores 1 in the
subfield R.
Example: reg0[6] = check_pkt_larger(1000);
log(key=value, ...);
Causes ovn-controller to log the packet on the
chassis that processes it. Packet logging currently
uses the same logging mechanism as other Open
vSwitch and OVN messages, which means that whether
and where log messages appear depends on the local
logging configuration that can be configured with
ovs-appctl, etc.
The log action takes zero or more of the following
key-value pair arguments that control what is
logged:
name=string
An optional name for the ACL. The string is
currently limited to 64 bytes.
severity=level
Indicates the severity of the event. The
level is one of following (from more to less
serious): alert, warning, notice, info, or
debug. If a severity is not provided, the
default is info.
verdict=value
The verdict for packets matching the flow.
The value must be one of allow, deny, or
reject.
meter=string
An optional rate-limiting meter to be
applied to the logs. The string should
reference a name entry from the Meter table.
The only meter action that is appropriate is
drop.
fwd_group(liveness=bool, childports=port, ...);
Parameters: optional liveness, either true or
false, defaulting to false; childports, a comma-
delimited list of strings denoting logical ports to
load balance across.
Load balance traffic to one or more child ports in
a logical switch. ovn-controller translates the
fwd_group into an OpenFlow group with one bucket
for each child port. If liveness=true is specified,
it also integrates the bucket selection with BFD
status on the tunnel interface corresponding to
child port.
Example: fwd_group(liveness=true, childports="p1",
"p2");
icmp4 { action; ... };
icmp4_error { action; ... };
Temporarily replaces the IPv4 packet being processed
by an ICMPv4 packet and executes each nested action
on the ICMPv4 packet. Actions following these
actions, if any, apply to the original, unmodified
packet.
The ICMPv4 packet that these actions operates on is
initialized based on the IPv4 packet being processed,
as follows. These are default values that the nested
actions will probably want to change. Ethernet and
IPv4 fields not listed here are not changed:
• ip.proto = 1 (ICMPv4)
• ip.frag = 0 (not a fragment)
• ip.ttl = 255
• icmp4.type = 3 (destination unreachable)
• icmp4.code = 1 (host unreachable)
icmp4_error action is expected to be used to generate
an ICMPv4 packet in response to an error in original
IP packet. When this action generates the ICMPv4
packet, it also copies the original IP datagram
following the ICMPv4 header as per RFC 1122: 3.2.2.
Prerequisite: ip4
icmp6 { action; ... };
icmp6_error { action; ... };
Temporarily replaces the IPv6 packet being processed
by an ICMPv6 packet and executes each nested action
on the ICMPv6 packet. Actions following the icmp6
action, if any, apply to the original, unmodified
packet.
The ICMPv6 packet that this action operates on is
initialized based on the IPv6 packet being processed,
as follows. These are default values that the nested
actions will probably want to change. Ethernet and
IPv6 fields not listed here are not changed:
• ip.proto = 58 (ICMPv6)
• ip.ttl = 255
• icmp6.type = 1 (destination unreachable)
• icmp6.code = 1 (administratively prohibited)
icmp6_error action is expected to be used to generate
an ICMPv6 packet in response to an error in original
IPv6 packet.
Prerequisite: ip6
tcp_reset;
This action transforms the current TCP packet
according to the following pseudocode:
if (tcp.ack) {
tcp.seq = tcp.ack;
} else {
tcp.ack = tcp.seq + length(tcp.payload);
tcp.seq = 0;
}
tcp.flags = RST;
Then, the action drops all TCP options and payload
data, and updates the TCP checksum. IP ttl is set to
255.
Prerequisite: tcp
reject { action; ... };
If the original packet is IPv4 or IPv6 TCP packet, it
replaces it with IPv4 or IPv6 TCP RST packet and
executes the inner actions. Otherwise it replaces it
with an ICMPv4 or ICMPv6 packet and executes the
inner actions.
The inner actions should not attempt to swap eth
source with eth destination and IP source with IP
destination as this action implicitly does that.
trigger_event;
This action is used to allow ovs-vswitchd to report
CMS related events writing them in Controller_Event
table. It is possible to associate a meter to a each
event in order to not overload pinctrl thread under
heavy load; each meter is identified though a defined
naming convention. Supported events:
• empty_lb_backends. This event is raised if a
received packet is destined for a load
balancer VIP that has no configured backend
destinations. For this event, the event info
includes the load balancer VIP, the load
balancer UUID, and the transport protocol.
Associated meter: event-elb
igmp;
This action sends the packet to ovn-controller for
multicast snooping.
Prerequisite: igmp
bind_vport(V, P);
Parameters: logical port string field V of type
virtual, logical port string field P.
Binds the virtual logical port V and sets the chassis
column and virtual_parent of the table Port_Binding.
virtual_parent is set to P.
handle_svc_check(P);
Parameters: logical port string field P.
Handles the service monitor reply received from the
VIF of the logical port P. ovn-controller
periodically sends out the service monitor packets
for the services configured in the Service_Monitor
table and this action updates the status of those
services.
Example: handle_svc_check(inport);
handle_dhcpv6_reply;
Handle DHCPv6 prefix delegation
advertisements/replies from a IPv6 delegation server.
ovn-controller will add an entry ipv6_ra_pd_list in
the options table for each prefix received from the
delegation server
R = select(N1[=W1], N2[=W2], ...);
Parameters: Integer N1, N2..., with optional weight
W1, W2, ...
Result: stored to a logical field or subfield R.
Select from a list of integers N1, N2..., each within
the range 0 ~ 65535, and store the selected one in
the field R. There must be 2 or more integers listed,
each with an optional weight, which is an integer
within the range 1 ~ 65535. If weight is not
specified, it defaults to 100. The selection method
is based on the 5-tuple hash of packet header.
Processing automatically moves on to the next table,
as if next; were specified. The select action must be
put as the last action of the logical flow when there
are multiple actions (actions put after select will
not take effect).
Example: reg8[16..31] = select(1=20, 2=30, 3=50);
handle_dhcpv6_reply;
This action is used to parse DHCPv6 replies from IPv6
Delegation Router and managed IPv6 Prefix delegation
state machine
R = chk_lb_hairpin();
This action checks if the packet under consideration
was destined to a load balancer VIP and it is
hairpinned, i.e., after load balancing the
destination IP matches the source IP. If it is so,
then the 1-bit destination register R is set to 1.
R = chk_lb_hairpin_reply();
This action checks if the packet under consideration
is from one of the backend IP of a load balancer VIP
and the destination IP is the load balancer VIP. If
it is so, then the 1-bit destination register R is
set to 1.
R = ct_snat_to_vip;
This action sends the packet through the SNAT zone to
change the source IP address of the packet to the
load balancer VIP if the original destination IP was
load balancer VIP and commits the connection. This
action applies successfully only for the hairpinned
traffic i.e if the action chk_lb_hairpin returned
success. This action doesn’t take any arguments and
it determines the SNAT IP internally. The packet is
not automatically sent to the next table. The caller
has to execute the next; action explicitly after this
action to advance the packet to the next stage.
R = check_in_port_sec();
This action checks if the packet under consideration
passes the inport port security checks. If the packet
fails the port security checks, then 1 is stored in
the destination register R. Else 0 is stored. The
port security values to check are retrieved from the
the inport logical port.
This action should be used in the ingress logical
switch pipeline.
Example: reg8[0..7] = check_in_port_sec();
R = check_out_port_sec();
This action checks if the packet under consideration
passes the outport port security checks. If the
packet fails the port security checks, then 1 is
stored in the destination register R. Else 0 is
stored. The port security values to check are
retrieved from the the outport logical port.
This action should be used in the egress logical
switch pipeline.
Example: reg8[0..7] = check_out_port_sec();
commit_ecmp_nh(ipv6);
Parameters: IPv4/IPv6 traffic.
This action translates to an openflow "learn" action
that inserts two new flows in tables 76 and 77.
• Match on the the 5-tuple and the expected
next-hop mac address in table 76: nw_src=ip0,
nw_dst=ip1, ip_proto,tp_src=l4_port0,
tp_dst=l4_port1,dl_src=ethaddr and set
reg9[5].
• Match on the 5-tuple in table 77: nw_src=ip1,
nw_dst=ip0, ip_proto, tp_src=l4_port1,
tp_dst=l4_port0 and set reg9[5] to 1
This action is applied if the packet arrives via ECMP
route or if it is routed via an ECMP route
R = check_ecmp_nh_mac();
This action checks if the packet under consideration
matches any flow in table 76. If it is so, then the
1-bit destination register R is set to 1.
R = check_ecmp_nh();
This action checks if the packet under consideration
matches the any flow in table 77. If it is so, then
the 1-bit destination register R is set to 1.
commit_lb_aff(vip, backend, proto, timeout);
Parameters: load-balancer virtual ip:port vip, load-
balancer backend ip:port backend, load-balancer
protocol proto, affinity timeout timeout.
This action translates to an openflow "learn" action
that inserts a new flow in table 78.
• Match on the 4-tuple in table 78: nw_src=ip
client, nw_dst=vip ip, ip_proto, tp_dst=vip
port and set reg9[6] to 1, reg4 and reg8 to
backend ip and port respectively. For IPv6
register xxreg1 is used to store the backend
ip.
This action is applied for new connections received
by a specific load-balacer with affinity timeout
configured.
R = chk_lb_aff();
This action checks if the packet under consideration
matches any flow in table 78. If it is so, then the
1-bit destination register R is set to 1.
sample(probability=packets, ...)
This action causes the matched traffic to be sampled
using IPFIX protocol. More information about how per-
flow IPFIX sampling works in OVS can be found in
ovs-actions(7) and ovs-vswitchd.conf.db(5).
In order to reliably identify each sampled packet
when it is received by the IPFIX collector, this
action sets the content of the ObservationDomainID
and ObservationPointID IPFIX fields (see argument
description below).
The following key-value arguments are supported:
probability=packets
The number of sampled packets out of 65535. It
must be greater or equal to 1.
collector_set=id
The unsigned 32-bit integer identifier of the
sample collector to send sampled packets to.
It must match the value configured in the
Flow_Sample_Collector_Set Table in OVS.
Defaults to 0.
obs_domain=id
An unsigned 8-bit integer that identifies the
sampling application. It will be placed in the
8 most significant bits of the
ObservationDomainID field of IPFIX samples.
The 24 less significant bits will be
automatically filled in with the datapath key.
Defaults to 0.
obs_point=id
An unsigned 32-bit integer to be used as
ObsservationPointID or the string @cookie to
indicate that the first 32 bits of the
Logical_Flow’s UUID shall be used instead.
mac_cache_use;
This action resubmits to corresponding table which
updates the use statistics of MAC cache.
R = dhcp_relay_req_chk(relay-ip,
server-ip); Parameters: Logical Router Port IP relay-
ip, DHCP Server IP server-ip.
Result: stored to a 1-bit subfield R.
This action executes on the source node on which the
DHCP request (DHCPDISCOVER or DHCPREQUEST)
originated.
When this action applied successfully on the DHCP
request packet, it updates GIADDR in the DHCP packet
with relay-ip and stores 1 in R.
When this action failed to apply on the packet, it
leaves the packet unchanged and stores 0 in R.
R = dhcp_relay_resp_chk(relay-ip,
server-ip); Parameters: Logical Router Port IP relay-
ip, DHCP Server IP server-ip.
Result: stored to a 1-bit subfield R.
This action executes on the first node (Redirect
Chassis node) which processes the DHCP
response(DHCPOFFER, DHCPACK) from the DHCP server.
When this action applied successfully on the DHCP
response packet, it updates the destination MAC and
destination IP in the packet and stores 1 in R.
relay-ip and server-ip are used to validate GIADDR
and SERVER-ID in the DHCP response packet.
When this action failed to apply on the packet, it
leaves the packet unchanged and stores 0 in R.
tags: map of string-string pairs
Key-value pairs that provide additional information to
help ovn-controller processing the logical flow. Below are
the tags used by ovn-controller.
in_out_port
In the logical flow’s "match" column, if a logical
port P is compared with "inport" and the logical
flow is on a logical switch ingress pipeline, or if
P is compared with "outport" and the logical flow
is on a logical switch egress pipeline, and the
expression is combined with other expressions (if
any) using the operator &&, then the port P should
be added as the value in this tag. If there are
multiple logical ports meeting this criteria, one
of them can be added. ovn-controller uses this
information to skip parsing flows that are not
needed on the chassis. Failing to add the tag will
affect efficiency, while adding wrong value will
affect correctness.
controller_meter: optional string
The name of the meter in table Meter to be used for all
packets that the logical flow might send to
ovn-controller.
external_ids : stage-name: optional string
Human-readable name for this flow’s stage in the pipeline.
external_ids : stage-hint: optional string, containing an uuid
UUID of a OVN_Northbound record that caused this logical
flow to be created. Currently used only for attribute of
logical flows to northbound ACL records.
external_ids : source: optional string
Source file and line number of the code that added this
flow to the pipeline.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
Each row in this table represents a group of logical datapaths
referenced by the logical_dp_group column in the Logical_Flow
table.
Summary:
datapaths set of weak reference to
Datapath_Bindings
Details:
datapaths: set of weak reference to Datapath_Bindings
List of Datapath_Binding entries.
The rows in this table define multicast groups of logical ports.
Multicast groups allow a single packet transmitted over a tunnel
to a hypervisor to be delivered to multiple VMs on that
hypervisor, which uses bandwidth more efficiently.
Each row in this table defines a logical multicast group numbered
tunnel_key within datapath, whose logical ports are listed in the
ports column.
Summary:
datapath Datapath_Binding
tunnel_key integer, in range 32,768 to 65,535
name string
ports set of weak reference to
Port_Bindings
Details:
datapath: Datapath_Binding
The logical datapath in which the multicast group resides.
tunnel_key: integer, in range 32,768 to 65,535
The value used to designate this logical egress port in
tunnel encapsulations. An index forces the key to be
unique within the datapath. The unusual range ensures that
multicast group IDs do not overlap with logical port IDs.
name: string
The logical multicast group’s name. An index forces the
name to be unique within the datapath. Logical flows in
the ingress pipeline may output to the group just as for
individual logical ports, by assigning the group’s name to
outport and executing an output action.
Multicast group names and logical port names share a
single namespace and thus should not overlap (but the
database schema cannot enforce this). To try to avoid
conflicts, ovn-northd uses names that begin with _MC_.
ports: set of weak reference to Port_Bindings
The logical ports included in the multicast group. All of
these ports must be in the datapath logical datapath (but
the database schema cannot enforce this).
Each row in this table represents a mirror that can be used for
port mirroring. These mirrors are referenced by the mirror_rules
column in the Port_Binding table.
Summary:
name string (must be unique within
table)
filter string, one of both, from-lport, or
to-lport
sink string
type string, one of erspan, gre, or
local
index integer
external_ids map of string-string pairs
Details:
name: string (must be unique within table)
Represents the name of the mirror.
filter: string, one of both, from-lport, or to-lport
The value of this field represents selection criteria of
the mirror. to-lport mirrors the packets coming into
logical port. from-lport mirrors the packets going out of
logical port. both mirrors for both directions.
sink: string
The value of this field represents the destination/sink of
the mirror. If the type is gre or erspan, the value
indicates the tunnel remote IP (either IPv4 or IPv6). For
a type of local, this field defines a local interface on
the OVS integration bridge to be used as the mirror
destination. The interface must possess external-
ids:mirror-id that matches this string.
type: string, one of erspan, gre, or local
The value of this field specifies the mirror type - gre,
erspan or local.
index: integer
The value of this field represents the tunnel ID. If the
configured tunnel type is gre, this field represents the
GRE key value and if the configured tunnel type is erspan
it represents the erspan_idx value. It is ignored if the
type is local.
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Each row in this table represents a meter that can be used for
QoS or rate-limiting.
Summary:
name string (must be unique within
table)
unit string, either kbps or pktps
bands set of 1 or more Meter_Bands
Details:
name: string (must be unique within table)
A name for this meter.
Names that begin with "__" (two underscores) are reserved
for OVN internal use and should not be added manually.
unit: string, either kbps or pktps
The unit for rate and burst_rate parameters in the bands
entry. kbps specifies kilobits per second, and pktps
specifies packets per second.
bands: set of 1 or more Meter_Bands
The bands associated with this meter. Each band specifies
a rate above which the band is to take the action action.
If multiple bands’ rates are exceeded, then the band with
the highest rate among the exceeded bands is selected.
Each row in this table represents a meter band which specifies
the rate above which the configured action should be applied.
These bands are referenced by the bands column in the Meter
table.
Summary:
action string, must be drop
rate integer, in range 1 to
4,294,967,295
burst_size integer, in range 0 to
4,294,967,295
Details:
action: string, must be drop
The action to execute when this band matches. The only
supported action is drop.
rate: integer, in range 1 to 4,294,967,295
The rate limit for this band, in kilobits per second or
bits per second, depending on whether the parent Meter
entry’s unit column specified kbps or pktps.
burst_size: integer, in range 0 to 4,294,967,295
The maximum burst allowed for the band in kilobits or
packets, depending on whether kbps or pktps was selected
in the parent Meter entry’s unit column. If the size is
zero, the switch is free to select some reasonable value
depending on its configuration.
Each row in this table represents a logical datapath, which
implements a logical pipeline among the ports in the Port_Binding
table associated with it. In practice, the pipeline in a given
logical datapath implements either a logical switch or a logical
router.
The main purpose of a row in this table is provide a physical
binding for a logical datapath. A logical datapath does not have
a physical location, so its physical binding information is
limited: just tunnel_key. The rest of the data in this table does
not affect packet forwarding.
Summary:
tunnel_key integer, in range 1 to 16,777,215
(must be unique within table)
load_balancers set of uuids
OVN_Northbound Relationship:
external_ids : logical-switch
optional string, containing an uuid
external_ids : logical-router
optional string, containing an uuid
external_ids : interconn-ts
optional string
Naming:
external_ids : name optional string
external_ids : name2 optional string
Common Columns:
external_ids map of string-string pairs
Details:
tunnel_key: integer, in range 1 to 16,777,215 (must be unique
within table)
The tunnel key value to which the logical datapath is
bound. The Tunnel Encapsulation section in
ovn-architecture(7) describes how tunnel keys are
constructed for each supported encapsulation.
load_balancers: set of uuids
Not used anymore; kept for backwards compatibility of the
schema.
OVN_Northbound Relationship:
Each row in Datapath_Binding is associated with some logical
datapath. ovn-northd uses these keys to track the association of
a logical datapath with concepts in the OVN_Northbound database.
external_ids : logical-switch: optional string, containing an
uuid
For a logical datapath that represents a logical switch,
ovn-northd stores in this key the UUID of the
corresponding Logical_Switch row in the OVN_Northbound
database.
external_ids : logical-router: optional string, containing an
uuid
For a logical datapath that represents a logical router,
ovn-northd stores in this key the UUID of the
corresponding Logical_Router row in the OVN_Northbound
database.
external_ids : interconn-ts: optional string
For a logical datapath that represents a logical switch
that represents a transit switch for interconnection,
ovn-northd stores in this key the value of the same
interconn-ts key of the external_ids column of the
corresponding Logical_Switch row in the OVN_Northbound
database.
Naming:
ovn-northd copies these from the name fields in the
OVN_Northbound database, either from name and
external_ids:neutron:router_name in the Logical_Router table or
from name and external_ids:neutron:network_name in the
Logical_Switch table.
external_ids : name: optional string
A name for the logical datapath.
external_ids : name2: optional string
Another name for the logical datapath.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
Each row in this table binds a logical port to a realization. For
most logical ports, this means binding to some physical location,
for example by binding a logical port to a VIF that belongs to a
VM running on a particular hypervisor. Other logical ports, such
as logical patch ports, can be realized without a specific
physical location, but their bindings are still expressed through
rows in this table.
For every Logical_Switch_Port record in OVN_Northbound database,
ovn-northd creates a record in this table. ovn-northd populates
and maintains every column except the chassis and virtual_parent
columns, which it leaves empty in new records.
ovn-controller/ovn-controller-vtep populates the chassis column
for the records that identify the logical ports that are located
on its hypervisor/gateway, which
ovn-controller/ovn-controller-vtep in turn finds out by
monitoring the local hypervisor’s Open_vSwitch database, which
identifies logical ports via the conventions described in
IntegrationGuide.rst. (The exceptions are for Port_Binding
records with type of l3gateway, whose locations are identified by
ovn-northd via the options:l3gateway-chassis column in this
table. ovn-controller is still responsible to populate the
chassis column.)
ovn-controller also populates the virtual_parent column of
records whose type is virtual.
When a chassis shuts down gracefully, it should clean up the
chassis column that it previously had populated. (This is not
critical because resources hosted on the chassis are equally
unreachable regardless of whether their rows are present.) To
handle the case where a VM is shut down abruptly on one chassis,
then brought up again on a different one,
ovn-controller/ovn-controller-vtep must overwrite the chassis
column with new information.
Summary:
Core Features:
datapath Datapath_Binding
logical_port string (must be unique within
table)
encap optional weak reference to Encap
additional_encap set of weak reference to Encaps
chassis optional weak reference to Chassis
additional_chassis set of weak reference to Chassis
gateway_chassis set of Gateway_Chassises
ha_chassis_group optional HA_Chassis_Group
up optional boolean
tunnel_key integer, in range 1 to 32,767
mac set of strings
port_security set of strings
type string
requested_chassis optional weak reference to Chassis
requested_additional_chassis
set of weak reference to Chassis
mirror_rules set of weak reference to Mirrors
Patch Options:
options : peer optional string
nat_addresses set of strings
L3 Gateway Options:
options : peer optional string
options : l3gateway-chassis
optional string
nat_addresses set of strings
Localnet Options:
options : network_name optional string
tag optional integer, in range 1 to
4,095
L2 Gateway Options:
options : network_name optional string
options : l2gateway-chassis
optional string
tag optional integer, in range 1 to
4,095
VTEP Options:
options : vtep-physical-switch
optional string
options : vtep-logical-switch
optional string
VMI (or VIF) Options:
options : requested-chassis
optional string
options : activation-strategy
optional string
options : additional-chassis-activated
optional string
options : iface-id-ver optional string
options : qos_min_rate optional string
options : qos_max_rate optional string
options : qos_burst optional string
options : qos_physical_network
optional string
options : qdisc_queue_id optional string, containing an
integer, in range 1 to 61,440
Distributed Gateway Port Options:
options : chassis-redirect-port
optional string
Chassis Redirect Options:
options : distributed-port optional string
options : redirect-type optional string
options : always-redirect optional string
Nested Containers:
parent_port optional string
tag optional integer, in range 1 to
4,095
Virtual ports:
virtual_parent optional string
Naming:
external_ids : name optional string
Common Columns:
external_ids map of string-string pairs
Details:
Core Features:
datapath: Datapath_Binding
The logical datapath to which the logical port belongs.
logical_port: string (must be unique within table)
A logical port. For a logical switch port, this is taken
from name in the OVN_Northbound database’s
Logical_Switch_Port table. For a logical router port, this
is taken from name in the OVN_Northbound database’s
Logical_Router_port table. (This means that logical switch
ports and router port names must not share names in an OVN
deployment.) OVN does not prescribe a particular format
for the logical port ID.
encap: optional weak reference to Encap
Points to preferred encapsulation configuration to
transmit logical dataplane packets to this chassis. The
entry is reference to a Encap record.
additional_encap: set of weak reference to Encaps
Points to preferred encapsulation configuration to
transmit logical dataplane packets to this additional
chassis. The entry is reference to a Encap record. See
also additional_chassis.
chassis: optional weak reference to Chassis
The meaning of this column depends on the value of the
type column. This is the meaning for each type
(empty string)
The physical location of the logical port. To
successfully identify a chassis, this column must
be a Chassis record. This is populated by
ovn-controller.
vtep The physical location of the hardware_vtep gateway.
To successfully identify a chassis, this column
must be a Chassis record. This is populated by
ovn-controller-vtep.
localnet
Always empty. A localnet port is realized on every
chassis that has connectivity to the corresponding
physical network.
localport
Always empty. A localport port is present on every
chassis.
l3gateway
The physical location of the L3 gateway. To
successfully identify a chassis, this column must
be a Chassis record. This is populated by
ovn-controller based on the value of the
options:l3gateway-chassis column in this table.
l2gateway
The physical location of this L2 gateway. To
successfully identify a chassis, this column must
be a Chassis record. This is populated by
ovn-controller based on the value of the
options:l2gateway-chassis column in this table.
additional_chassis: set of weak reference to Chassis
The meaning of this column is the same as for the chassis.
The column is used to track an additional physical
location of the logical port. Used with regular (empty
type) port bindings.
gateway_chassis: set of Gateway_Chassises
A list of Gateway_Chassis.
This should only be populated for ports with type set to
chassisredirect. This column defines the list of chassis
used as gateways where traffic will be redirected through.
ha_chassis_group: optional HA_Chassis_Group
This should only be populated for ports with type set to
chassisredirect. This column defines the HA chassis group
with a list of HA chassis used as gateways where traffic
will be redirected through.
up: optional boolean
This is set to true whenever all OVS flows required by
this Port_Binding have been installed. This is populated
by ovn-controller.
tunnel_key: integer, in range 1 to 32,767
A number that represents the logical port in the key (e.g.
STT key or Geneve TLV) field carried within tunnel
protocol packets.
The tunnel ID must be unique within the scope of a logical
datapath.
mac: set of strings
This column is a misnomer as it may contain MAC addresses
and IP addresses. It is copied from the addresses column
in the Logical_Switch_Port table in the Northbound
database. It follows the same format as that column.
port_security: set of strings
This column controls the addresses from which the host
attached to the logical port (``the host’’) is allowed to
send packets and to which it is allowed to receive
packets. If this column is empty, all addresses are
permitted.
It is copied from the port_security column in the
Logical_Switch_Port table in the Northbound database. It
follows the same format as that column.
type: string
A type for this logical port. Logical ports can be used to
model other types of connectivity into an OVN logical
switch. The following types are defined:
(empty string)
VM (or VIF) interface.
patch One of a pair of logical ports that act as if
connected by a patch cable. Useful for connecting
two logical datapaths, e.g. to connect a logical
router to a logical switch or to another logical
router.
l3gateway
One of a pair of logical ports that act as if
connected by a patch cable across multiple chassis.
Useful for connecting a logical switch with a
Gateway router (which is only resident on a
particular chassis).
localnet
A connection to a locally accessible network from
ovn-controller instances that have a corresponding
bridge mapping. A logical switch can have multiple
localnet ports attached. This type is used to model
direct connectivity to existing networks. In this
case, each chassis should have a mapping for one of
the physical networks only. Note: nothing said
above implies that a chassis cannot be plugged to
multiple physical networks as long as they belong
to different switches.
localport
A connection to a local VIF. Traffic that arrives
on a localport is never forwarded over a tunnel to
another chassis. These ports are present on every
chassis and have the same address in all of them.
This is used to model connectivity to local
services that run on every hypervisor.
l2gateway
An L2 connection to a physical network. The chassis
this Port_Binding is bound to will serve as an L2
gateway to the network named by
options:network_name.
vtep A port to a logical switch on a VTEP gateway
chassis. In order to get this port correctly
recognized by the OVN controller, the
options:vtep-physical-switch and
options:vtep-logical-switch must also be defined.
chassisredirect
A logical port that represents a particular
instance, bound to a specific chassis, of an
otherwise distributed parent port (e.g. of type
patch). A chassisredirect port should never be used
as an inport. When an ingress pipeline sets the
outport, it may set the value to a logical port of
type chassisredirect. This will cause the packet to
be directed to a specific chassis to carry out the
egress pipeline. At the beginning of the egress
pipeline, the outport will be reset to the value of
the distributed port.
virtual
Represents a logical port with an virtual ip. This
virtual ip can be configured on a logical port
(which is referred as virtual parent).
requested_chassis: optional weak reference to Chassis
This column exists so that the ovn-controller can
effectively monitor all Port_Binding records destined for
it, and is a supplement to the options:requested-chassis
option. The option is still required so that the ovn-
controller can check the CMS intent when the chassis
pointed to does not currently exist, which for example
occurs when the ovn-controller is stopped without passing
the -restart argument. This column must be a Chassis
record. This is populated by ovn-northd when the
options:requested-chassis is defined and contains a string
matching the name or hostname of an existing chassis. See
also requested_additional_chassis.
requested_additional_chassis: set of weak reference to Chassis
This column exists so that the ovn-controller can
effectively monitor all Port_Binding records destined for
it, and is a supplement to the options:requested-chassis
option when multiple chassis are listed. This column must
be a list of Chassis records. This is populated by
ovn-northd when the options:requested-chassis is defined
as a list of chassis names or hostnames. See also
requested_chassis.
mirror_rules: set of weak reference to Mirrors
Mirror rules that apply to the port binding. Please see
the Mirror table.
Patch Options:
These options apply to logical ports with type of patch.
options : peer: optional string
The logical_port in the Port_Binding record for the other
side of the patch. The named logical_port must specify
this logical_port in its own peer option. That is, the two
patch logical ports must have reversed logical_port and
peer values.
nat_addresses: set of strings
MAC address followed by a list of SNAT and DNAT external
IP addresses, followed by is_chassis_resident("lport"),
where lport is the name of a logical port on the same
chassis where the corresponding NAT rules are applied.
This is used to send gratuitous ARPs for SNAT and DNAT
external IP addresses via localnet, from the chassis where
lport resides. Example: 80:fa:5b:06:72:b7 158.36.44.22
158.36.44.24 is_chassis_resident("foo1"). This would
result in generation of gratuitous ARPs for IP addresses
158.36.44.22 and 158.36.44.24 with a MAC address of
80:fa:5b:06:72:b7 from the chassis where the logical port
"foo1" resides.
L3 Gateway Options:
These options apply to logical ports with type of l3gateway.
options : peer: optional string
The logical_port in the Port_Binding record for the other
side of the ’l3gateway’ port. The named logical_port must
specify this logical_port in its own peer option. That is,
the two ’l3gateway’ logical ports must have reversed
logical_port and peer values.
options : l3gateway-chassis: optional string
The chassis in which the port resides.
nat_addresses: set of strings
MAC address of the l3gateway port followed by a list of
SNAT and DNAT external IP addresses. This is used to send
gratuitous ARPs for SNAT and DNAT external IP addresses
via localnet. Example: 80:fa:5b:06:72:b7 158.36.44.22
158.36.44.24. This would result in generation of
gratuitous ARPs for IP addresses 158.36.44.22 and
158.36.44.24 with a MAC address of 80:fa:5b:06:72:b7. This
is used in OVS version 2.8 and later versions.
Localnet Options:
These options apply to logical ports with type of localnet.
options : network_name: optional string
Required. ovn-controller uses the configuration entry
ovn-bridge-mappings to determine how to connect to this
network. ovn-bridge-mappings is a list of network names
mapped to a local OVS bridge that provides access to that
network. An example of configuring ovn-bridge-mappings
would be: .IP
$ ovs-vsctl set open . external-ids:ovn-bridge-mappings=physnet1:br-eth0,physnet2:br-eth1
When a logical switch has a localnet port attached, every
chassis that may have a local vif attached to that logical
switch must have a bridge mapping configured to reach that
localnet. Traffic that arrives on a localnet port is never
forwarded over a tunnel to another chassis. If there are
multiple localnet ports in a logical switch, each chassis
should only have a single bridge mapping for one of the
physical networks. Note: In case of multiple localnet
ports, to provide interconnectivity between all VIFs
located on different chassis with different fabric
connectivity, the fabric should implement some form of
routing between the segments.
tag: optional integer, in range 1 to 4,095
If set, indicates that the port represents a connection to
a specific VLAN on a locally accessible network. The VLAN
ID is used to match incoming traffic and is also added to
outgoing traffic.
L2 Gateway Options:
These options apply to logical ports with type of l2gateway.
options : network_name: optional string
Required. ovn-controller uses the configuration entry
ovn-bridge-mappings to determine how to connect to this
network. ovn-bridge-mappings is a list of network names
mapped to a local OVS bridge that provides access to that
network. An example of configuring ovn-bridge-mappings
would be: .IP
$ ovs-vsctl set open . external-ids:ovn-bridge-mappings=physnet1:br-eth0,physnet2:br-eth1
When a logical switch has a l2gateway port attached, the
chassis that the l2gateway port is bound to must have a
bridge mapping configured to reach the network identified
by network_name.
options : l2gateway-chassis: optional string
Required. The chassis in which the port resides.
tag: optional integer, in range 1 to 4,095
If set, indicates that the gateway is connected to a
specific VLAN on the physical network. The VLAN ID is used
to match incoming traffic and is also added to outgoing
traffic.
VTEP Options:
These options apply to logical ports with type of vtep.
options : vtep-physical-switch: optional string
Required. The name of the VTEP gateway.
options : vtep-logical-switch: optional string
Required. A logical switch name connected by the VTEP
gateway. Must be set when type is vtep.
VMI (or VIF) Options:
These options apply to logical ports with type having (empty
string)
options : requested-chassis: optional string
If set, identifies a specific chassis (by name or
hostname) that is allowed to bind this port. Using this
option will prevent thrashing between two chassis trying
to bind the same port during a live migration. It can also
prevent similar thrashing due to a mis-configuration, if a
port is accidentally created on more than one chassis.
If set to a comma separated list, the first entry
identifies the main chassis and the rest are one or more
additional chassis that are allowed to bind the same port.
When multiple chassis are set for the port, and the
logical switch is connected to an external network through
a localnet port, tunneling is enforced for the port to
guarantee delivery of packets directed to the port to all
its locations. This has MTU implications because the
network used for tunneling must have MTU larger than
localnet for stable connectivity.
options : activation-strategy: optional string
If used with multiple chassis set in requested-chassis,
specifies an activation strategy for all additional
chassis. By default, no activation strategy is used,
meaning additional port locations are immediately
available for use. When set to "rarp", the port is blocked
for ingress and egress communication until a RARP packet
is sent from a new location. The "rarp" strategy is useful
in live migration scenarios for virtual machines.
options : additional-chassis-activated: optional string
When activation-strategy is set, this option indicates
that the port was activated using the strategy specified.
options : iface-id-ver: optional string
If set, this port will be bound by ovn-controller only if
this same key and value is configured in the external_ids
column in the Open_vSwitch database’s Interface table.
options : qos_min_rate: optional string
If set, indicates the minimum guaranteed rate available
for data sent from this interface, in bit/s.
options : qos_max_rate: optional string
If set, indicates the maximum rate for data sent from this
interface, in bit/s. The traffic will be shaped according
to this limit.
options : qos_burst: optional string
If set, indicates the maximum burst size for data sent
from this interface, in bits.
options : qos_physical_network: optional string
If set, indicates the name of the egress network name
where traffic shaping will be applied.
options : qdisc_queue_id: optional string, containing an integer,
in range 1 to 61,440
Indicates the queue number on the physical device. This is
same as the queue_id used in OpenFlow in struct
ofp_action_enqueue.
Distributed Gateway Port Options:
These options apply to the distributed parent ports of logical
ports with type of chasssisredirect.
options : chassis-redirect-port: optional string
The name of the chassis redirect port derived from this
port if this port is a distributed parent of a chassis
redirect port.
Chassis Redirect Options:
These options apply to logical ports with type of
chassisredirect.
options : distributed-port: optional string
The name of the distributed port for which this
chassisredirect port represents a particular instance.
options : redirect-type: optional string
The value is copied from the column options in the
OVN_Northbound database’s Logical_Router_Port table for
the distributed parent of this port.
options : always-redirect: optional string
A boolean option that is set to true if the distributed
parent of this chassis redirect port does not need
distributed processing.
Nested Containers:
These columns support containers nested within a VM.
Specifically, they are used when type is empty and logical_port
identifies the interface of a container spawned inside a VM. They
are empty for containers or VMs that run directly on a
hypervisor.
parent_port: optional string
This is taken from parent_name in the OVN_Northbound
database’s Logical_Switch_Port table.
tag: optional integer, in range 1 to 4,095
Identifies the VLAN tag in the network traffic associated
with that container’s network interface.
This column is used for a different purpose when type is
localnet (see Localnet Options, above) or l2gateway (see
L2 Gateway Options, above).
Virtual ports:
virtual_parent: optional string
This column is set by ovn-controller with one of the value
from the options:virtual-parents in the OVN_Northbound
database’s Logical_Switch_Port table when the OVN action
bind_vport is executed. ovn-controller also sets the
chassis column when it executes this action with its
chassis id.
ovn-controller sets this column only if the type is
"virtual".
Naming:
external_ids : name: optional string
For a logical switch port, ovn-northd copies this from
external_ids:neutron:port_name in the Logical_Switch_Port
table in the OVN_Northbound database, if it is a nonempty
string.
For a logical switch port, ovn-northd does not currently
set this key.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
The ovn-northd program populates this column with all
entries into the external_ids column of the
Logical_Switch_Port and Logical_Router_Port tables of the
OVN_Northbound database.
Each row in this table specifies a binding from an IP address to
an Ethernet address that has been discovered through ARP (for
IPv4) or neighbor discovery (for IPv6). This table is primarily
used to discover bindings on physical networks, because IP-to-MAC
bindings for virtual machines are usually populated statically
into the Port_Binding table.
This table expresses a functional relationship:
MAC_Binding(logical_port, ip) = mac.
In outline, the lifetime of a logical router’s MAC binding looks
like this:
1. On hypervisor 1, a logical router determines that a
packet should be forwarded to IP address A on one of
its router ports. It uses its logical flow table to
determine that A lacks a static IP-to-MAC binding and
the get_arp action to determine that it lacks a
dynamic IP-to-MAC binding.
2. Using an OVN logical arp action, the logical router
generates and sends a broadcast ARP request to the
router port. It drops the IP packet.
3. The logical switch attached to the router port
delivers the ARP request to all of its ports. (It
might make sense to deliver it only to ports that have
no static IP-to-MAC bindings, but this could also be
surprising behavior.)
4. A host or VM on hypervisor 2 (which might be the same
as hypervisor 1) attached to the logical switch owns
the IP address in question. It composes an ARP reply
and unicasts it to the logical router port’s Ethernet
address.
5. The logical switch delivers the ARP reply to the
logical router port.
6. The logical router flow table executes a put_arp
action. To record the IP-to-MAC binding,
ovn-controller adds a row to the MAC_Binding table.
7. On hypervisor 1, ovn-controller receives the updated
MAC_Binding table from the OVN southbound database.
The next packet destined to A through the logical
router is sent directly to the bound Ethernet address.
Summary:
logical_port string
ip string
mac string
timestamp integer
datapath Datapath_Binding
Details:
logical_port: string
The logical port on which the binding was discovered.
ip: string
The bound IP address.
mac: string
The Ethernet address to which the IP is bound.
timestamp: integer
The timestamp in msec when the MAC binding was added or
updated. Records that existed before this column will have
0.
datapath: Datapath_Binding
The logical datapath to which the logical port belongs.
Each row in this table stores the DHCP Options supported by
native OVN DHCP. ovn-northd populates this table with the
supported DHCP options. ovn-controller looks up this table to get
the DHCP codes of the DHCP options defined in the "put_dhcp_opts"
action. Please refer to the RFC 2132
"https://tools.ietf.org/html/rfc2132" for the possible list of
DHCP options that can be defined here.
Summary:
name string
code integer, in range 0 to 254
type string, one of bool, domains,
host_id, ipv4, static_routes, str,
uint16, uint32, or uint8
Details:
name: string
Name of the DHCP option.
Example. name="router"
code: integer, in range 0 to 254
DHCP option code for the DHCP option as defined in the RFC
2132.
Example. code=3
type: string, one of bool, domains, host_id, ipv4, static_routes,
str, uint16, uint32, or uint8
Data type of the DHCP option code.
value: bool
This indicates that the value of the DHCP option is
a bool.
Example. "name=ip_forward_enable", "code=19",
"type=bool".
put_dhcp_opts(..., ip_forward_enable = 1,...)
value: uint8
This indicates that the value of the DHCP option is
an unsigned int8 (8 bits)
Example. "name=default_ttl", "code=23",
"type=uint8".
put_dhcp_opts(..., default_ttl = 50,...)
value: uint16
This indicates that the value of the DHCP option is
an unsigned int16 (16 bits).
Example. "name=mtu", "code=26", "type=uint16".
put_dhcp_opts(..., mtu = 1450,...)
value: uint32
This indicates that the value of the DHCP option is
an unsigned int32 (32 bits).
Example. "name=lease_time", "code=51",
"type=uint32".
put_dhcp_opts(..., lease_time = 86400,...)
value: ipv4
This indicates that the value of the DHCP option is
an IPv4 address or addresses.
Example. "name=router", "code=3", "type=ipv4".
put_dhcp_opts(..., router = 10.0.0.1,...)
Example. "name=dns_server", "code=6", "type=ipv4".
put_dhcp_opts(..., dns_server = {8.8.8.8
7.7.7.7},...)
value: static_routes
This indicates that the value of the DHCP option
contains a pair of IPv4 route and next hop
addresses.
Example. "name=classless_static_route", "code=121",
"type=static_routes".
put_dhcp_opts(..., classless_static_route =
{30.0.0.0/24,10.0.0.4,0.0.0.0/0,10.0.0.1}...)
value: str
This indicates that the value of the DHCP option is
a string.
Example. "name=host_name", "code=12", "type=str".
value: host_id
This indicates that the value of the DHCP option is
a host_id. It can either be a host_name or an IP
address.
Example. "name=tftp_server", "code=66",
"type=host_id".
value: domains
This indicates that the value of the DHCP option is
a domain name or a comma separated list of domain
names.
Example. "name=domain_search_list", "code=119",
"type=domains".
Each row in this table stores the DHCPv6 Options supported by
native OVN DHCPv6. ovn-northd populates this table with the
supported DHCPv6 options. ovn-controller looks up this table to
get the DHCPv6 codes of the DHCPv6 options defined in the
put_dhcpv6_opts action. Please refer to RFC 3315 and RFC 3646 for
the list of DHCPv6 options that can be defined here.
Summary:
name string
code integer, in range 0 to 254
type string, one of domain, ipv6, mac,
or str
Details:
name: string
Name of the DHCPv6 option.
Example. name="ia_addr"
code: integer, in range 0 to 254
DHCPv6 option code for the DHCPv6 option as defined in the
appropriate RFC.
Example. code=3
type: string, one of domain, ipv6, mac, or str
Data type of the DHCPv6 option code.
value: ipv6
This indicates that the value of the DHCPv6 option
is an IPv6 address(es).
Example. "name=ia_addr", "code=5", "type=ipv6".
put_dhcpv6_opts(..., ia_addr = ae70::4,...)
value: str
This indicates that the value of the DHCPv6 option
is a string.
Example. "name=domain_search", "code=24",
"type=str".
put_dhcpv6_opts(..., domain_search =
ovn.domain,...)
value: mac
This indicates that the value of the DHCPv6 option
is a MAC address.
Example. "name=server_id", "code=2", "type=mac".
put_dhcpv6_opts(..., server_id =
01:02:03:04L05:06,...)
Configuration for a database connection to an Open vSwitch
database (OVSDB) client.
This table primarily configures the Open vSwitch database server
(ovsdb-server).
The Open vSwitch database server can initiate and maintain active
connections to remote clients. It can also listen for database
connections.
Summary:
Core Features:
target string (must be unique within
table)
read_only boolean
role string
Client Failure Detection and Handling:
max_backoff optional integer, at least 1,000
inactivity_probe optional integer
Status:
is_connected boolean
status : last_error optional string
status : state optional string, one of ACTIVE,
BACKOFF, CONNECTING, IDLE, or VOID
status : sec_since_connect optional string, containing an
integer, at least 0
status : sec_since_disconnect
optional string, containing an
integer, at least 0
status : locks_held optional string
status : locks_waiting optional string
status : locks_lost optional string
status : n_connections optional string, containing an
integer, at least 2
status : bound_port optional string, containing an
integer
Common Columns:
external_ids map of string-string pairs
other_config map of string-string pairs
Details:
Core Features:
target: string (must be unique within table)
Connection methods for clients.
The following connection methods are currently supported:
ssl:host[:port]
The specified SSL port on the given host, which can
either be a DNS name (if built with unbound
library) or an IP address. A valid SSL
configuration must be provided when this form is
used, this configuration can be specified via
command-line options or the SSL table.
If port is not specified, it defaults to 6640.
SSL support is an optional feature that is not
always built as part of Open vSwitch.
tcp:host[:port]
The specified TCP port on the given host, which can
either be a DNS name (if built with unbound
library) or an IP address (IPv4 or IPv6). If host
is an IPv6 address, wrap it in square brackets,
e.g. tcp:[::1]:6640.
If port is not specified, it defaults to 6640.
pssl:[port][:host]
Listens for SSL connections on the specified TCP
port. Specify 0 for port to have the kernel
automatically choose an available port. If host,
which can either be a DNS name (if built with
unbound library) or an IP address, is specified,
then connections are restricted to the resolved or
specified local IP address (either IPv4 or IPv6
address). If host is an IPv6 address, wrap in
square brackets, e.g. pssl:6640:[::1]. If host is
not specified then it listens only on IPv4 (but not
IPv6) addresses. A valid SSL configuration must be
provided when this form is used, this can be
specified either via command-line options or the
SSL table.
If port is not specified, it defaults to 6640.
SSL support is an optional feature that is not
always built as part of Open vSwitch.
ptcp:[port][:host]
Listens for connections on the specified TCP port.
Specify 0 for port to have the kernel automatically
choose an available port. If host, which can either
be a DNS name (if built with unbound library) or an
IP address, is specified, then connections are
restricted to the resolved or specified local IP
address (either IPv4 or IPv6 address). If host is
an IPv6 address, wrap it in square brackets, e.g.
ptcp:6640:[::1]. If host is not specified then it
listens only on IPv4 addresses.
If port is not specified, it defaults to 6640.
When multiple clients are configured, the target values
must be unique. Duplicate target values yield unspecified
results.
read_only: boolean
true to restrict these connections to read-only
transactions, false to allow them to modify the database.
role: string
String containing role name for this connection entry.
Client Failure Detection and Handling:
max_backoff: optional integer, at least 1,000
Maximum number of milliseconds to wait between connection
attempts. Default is implementation-specific.
inactivity_probe: optional integer
Maximum number of milliseconds of idle time on connection
to the client before sending an inactivity probe message.
If Open vSwitch does not communicate with the client for
the specified number of seconds, it will send a probe. If
a response is not received for the same additional amount
of time, Open vSwitch assumes the connection has been
broken and attempts to reconnect. Default is
implementation-specific. A value of 0 disables inactivity
probes.
Status:
Key-value pair of is_connected is always updated. Other key-value
pairs in the status columns may be updated depends on the target
type.
When target specifies a connection method that listens for
inbound connections (e.g. ptcp: or punix:), both n_connections
and is_connected may also be updated while the remaining key-
value pairs are omitted.
On the other hand, when target specifies an outbound connection,
all key-value pairs may be updated, except the above-mentioned
two key-value pairs associated with inbound connection targets.
They are omitted.
is_connected: boolean
true if currently connected to this client, false
otherwise.
status : last_error: optional string
A human-readable description of the last error on the
connection to the manager; i.e. strerror(errno). This key
will exist only if an error has occurred.
status : state: optional string, one of ACTIVE, BACKOFF,
CONNECTING, IDLE, or VOID
The state of the connection to the manager:
VOID Connection is disabled.
BACKOFF
Attempting to reconnect at an increasing period.
CONNECTING
Attempting to connect.
ACTIVE Connected, remote host responsive.
IDLE Connection is idle. Waiting for response to keep-
alive.
These values may change in the future. They are provided
only for human consumption.
status : sec_since_connect: optional string, containing an
integer, at least 0
The amount of time since this client last successfully
connected to the database (in seconds). Value is empty if
client has never successfully been connected.
status : sec_since_disconnect: optional string, containing an
integer, at least 0
The amount of time since this client last disconnected
from the database (in seconds). Value is empty if client
has never disconnected.
status : locks_held: optional string
Space-separated list of the names of OVSDB locks that the
connection holds. Omitted if the connection does not hold
any locks.
status : locks_waiting: optional string
Space-separated list of the names of OVSDB locks that the
connection is currently waiting to acquire. Omitted if the
connection is not waiting for any locks.
status : locks_lost: optional string
Space-separated list of the names of OVSDB locks that the
connection has had stolen by another OVSDB client. Omitted
if no locks have been stolen from this connection.
status : n_connections: optional string, containing an integer,
at least 2
When target specifies a connection method that listens for
inbound connections (e.g. ptcp: or pssl:) and more than
one connection is actually active, the value is the number
of active connections. Otherwise, this key-value pair is
omitted.
status : bound_port: optional string, containing an integer
When target is ptcp: or pssl:, this is the TCP port on
which the OVSDB server is listening. (This is particularly
useful when target specifies a port of 0, allowing the
kernel to choose any available port.)
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
other_config: map of string-string pairs
SSL configuration for ovn-sb database access.
Summary:
private_key string
certificate string
ca_cert string
bootstrap_ca_cert boolean
ssl_protocols string
ssl_ciphers string
Common Columns:
external_ids map of string-string pairs
Details:
private_key: string
Name of a PEM file containing the private key used as the
switch’s identity for SSL connections to the controller.
certificate: string
Name of a PEM file containing a certificate, signed by the
certificate authority (CA) used by the controller and
manager, that certifies the switch’s private key,
identifying a trustworthy switch.
ca_cert: string
Name of a PEM file containing the CA certificate used to
verify that the switch is connected to a trustworthy
controller.
bootstrap_ca_cert: boolean
If set to true, then Open vSwitch will attempt to obtain
the CA certificate from the controller on its first SSL
connection and save it to the named PEM file. If it is
successful, it will immediately drop the connection and
reconnect, and from then on all SSL connections must be
authenticated by a certificate signed by the CA
certificate thus obtained. This option exposes the SSL
connection to a man-in-the-middle attack obtaining the
initial CA certificate. It may still be useful for
bootstrapping.
ssl_protocols: string
List of SSL protocols to be enabled for SSL connections.
The default when this option is omitted is
TLSv1,TLSv1.1,TLSv1.2.
ssl_ciphers: string
List of ciphers (in OpenSSL cipher string format) to be
supported for SSL connections. The default when this
option is omitted is HIGH:!aNULL:!MD5.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
Each row in this table stores the DNS records. The OVN action
dns_lookup uses this table for DNS resolution.
Summary:
records map of string-string pairs
datapaths set of 1 or more Datapath_Bindings
options : ovn-owned optional string
Common Columns:
external_ids map of string-string pairs
Details:
records: map of string-string pairs
Key-value pair of DNS records with DNS query name as the
key and a string of IP address(es) separated by comma or
space as the value. ovn-northd stores the DNS query name
in all lowercase in order to facilitate case-insensitive
lookups.
Example: "vm1.ovn.org" = "10.0.0.4 aef0::4"
datapaths: set of 1 or more Datapath_Bindings
The DNS records defined in the column records will be
applied only to the DNS queries originating from the
datapaths defined in this column.
options : ovn-owned: optional string
This column indicates that all the Domains in this table
are owned by OVN, and all DNS queries for those domains
will be answered locally by either an IP address or DNS
rejection.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Role table for role-based access controls.
Summary:
name string
permissions map of string-weak reference to
RBAC_Permission pairs
Details:
name: string
The role name, corresponding to the role column in the
Connection table.
permissions: map of string-weak reference to RBAC_Permission
pairs
A mapping of table names to rows in the RBAC_Permission
table.
Permissions table for role-based access controls.
Summary:
table string
authorization set of strings
insert_delete boolean
update set of strings
Details:
table: string
Name of table to which this row applies.
authorization: set of strings
Set of strings identifying columns and column:key pairs to
be compared with client ID. At least one match is required
in order to be authorized. A zero-length string is treated
as a special value indicating all clients should be
considered authorized.
insert_delete: boolean
When "true", row insertions and authorized row deletions
are permitted.
update: set of strings
Set of strings identifying columns and column:key pairs
that authorized clients are allowed to modify.
Association of Port_Binding rows of type chassisredirect to a
Chassis. The traffic going out through a specific chassisredirect
port will be redirected to a chassis, or a set of them in high
availability configurations.
Summary:
name string (must be unique within
table)
chassis optional weak reference to Chassis
priority integer, in range 0 to 32,767
options map of string-string pairs
Common Columns:
external_ids map of string-string pairs
Details:
name: string (must be unique within table)
Name of the Gateway_Chassis.
A suggested, but not required naming convention is
${port_name}_${chassis_name}.
chassis: optional weak reference to Chassis
The Chassis to which we send the traffic.
priority: integer, in range 0 to 32,767
This is the priority the specific Chassis among all
Gateway_Chassis belonging to the same Port_Binding.
options: map of string-string pairs
Reserved for future use.
Common Columns:
The overall purpose of these columns is described under Common
Columns at the beginning of this document.
external_ids: map of string-string pairs
Summary:
chassis optional weak reference to Chassis
priority integer, in range 0 to 32,767
Common Columns:
external_ids map of string-string pairs
Details:
chassis: optional weak reference to Chassis
The Chassis which provides the HA functionality.
priority: integer, in range 0 to 32,767
Priority of the HA chassis. Chassis with highest priority
will be the active chassis in the HA chassis group.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Table representing a group of chassis which can provide High
availability services. Each chassis in the group is represented
by the table HA_Chassis. The HA chassis with highest priority
will be the active chassis of this group. If the active chassis
failover is detected, the HA chassis with the next higher
priority takes over the responsibility of providing the HA. If
ha_chassis_group column of the table Port_Binding references this
table, then this HA chassis group provides the gateway
functionality and redirects the gateway traffic to the active
chassis of this group.
Summary:
name string (must be unique within
table)
ha_chassis set of HA_Chassises
ref_chassis set of weak reference to Chassis
Common Columns:
external_ids map of string-string pairs
Details:
name: string (must be unique within table)
Name of the HA_Chassis_Group. Name should be unique.
ha_chassis: set of HA_Chassises
A list of HA_Chassis which belongs to this group.
ref_chassis: set of weak reference to Chassis
The set of Chassis that reference this HA chassis group.
To determine the correct Chassis, find the chassisredirect
type Port_Binding that references this HA_Chassis_Group.
This Port_Binding is derived from some particular logical
router. Starting from that LR, find the set of all logical
switches and routers connected to it, directly or
indirectly, across router ports that link one LRP to
another or to a LSP. For each LSP in these logical
switches, find the corresponding Port_Binding and add its
bound Chassis (if any) to ref_chassis.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Database table used by ovn-controller to report CMS related
events. Please note there is no guarantee a given event is
written exactly once in the db. It is CMS responsibility to
squash duplicated lines or to filter out duplicated events
Summary:
event_type string, must be empty_lb_backends
event_info map of string-string pairs
chassis optional weak reference to Chassis
seq_num integer
Details:
event_type: string, must be empty_lb_backends
Event type occurred
event_info: map of string-string pairs
Key-value pairs used to specify event info to the CMS.
Possible values are:
• vip: VIP reported for the empty_lb_backends event
• protocol: Transport protocol reported for the
empty_lb_backends event
• load_balancer: UUID of the load balancer reported
for the empty_lb_backends event
chassis: optional weak reference to Chassis
This column is a Chassis record to identify the chassis
that has managed a given event.
seq_num: integer
Event sequence number. Global counter for controller
generated events. It can be used by the CMS to detect
possible duplication of the same event.
IP Multicast configuration options. For now only applicable to
IGMP.
Summary:
datapath weak reference to Datapath_Binding
(must be unique within table)
enabled optional boolean
querier optional boolean
table_size optional integer
idle_timeout optional integer
query_interval optional integer
seq_no integer
Querier configuration options:
eth_src string
ip4_src string
ip6_src string
query_max_resp optional integer
Details:
datapath: weak reference to Datapath_Binding (must be unique
within table)
Datapath_Binding entry for which these configuration
options are defined.
enabled: optional boolean
Enables/disables multicast snooping. Default: disabled.
querier: optional boolean
Enables/disables multicast querying. If enabled then
multicast querying is enabled by default.
table_size: optional integer
Limits the number of multicast groups that can be learned.
Default: 2048 groups per datapath.
idle_timeout: optional integer
Configures the idle timeout (in seconds) for IP multicast
groups if multicast snooping is enabled. Default: 300
seconds.
query_interval: optional integer
Configures the interval (in seconds) for sending multicast
queries if snooping and querier are enabled. Default:
idle_timeout/2 seconds.
seq_no: integer
ovn-controller reads this value and flushes all learned
multicast groups when it detects that seq_no was changed.
Querier configuration options:
The ovn-controller process that runs on OVN hypervisor nodes uses
the following columns to determine field values in IGMP/MLD
queries that it originates:
eth_src: string
Source Ethernet address.
ip4_src: string
Source IPv4 address.
ip6_src: string
Source IPv6 address.
query_max_resp: optional integer
Value (in seconds) to be used as "max-response" field in
multicast queries. Default: 1 second.
Contains learned IGMP groups indexed by address/datapath/chassis.
Summary:
address string
protocol string
datapath optional weak reference to
Datapath_Binding
chassis optional weak reference to Chassis
ports set of weak reference to
Port_Bindings
chassis_name string
Details:
address: string
Destination IPv4 address for the IGMP group.
protocol: string
Group protocol version either IGMPv1,v2,v3 or MLDv1,v2.
datapath: optional weak reference to Datapath_Binding
Datapath to which this IGMP group belongs.
chassis: optional weak reference to Chassis
Chassis to which this IGMP group belongs.
ports: set of weak reference to Port_Bindings
The destination port bindings for this IGMP group.
chassis_name: string
The chassis that inserted this record. This column is used
for RBAC purposes only.
Each row in this table configures monitoring a service for its
liveness. The service can be an IPv4 TCP or UDP service.
ovn-controller periodically sends out service monitor packets and
updates the status of the service.
ovn-northd uses this feature to implement the load balancer
health check feature offered to the CMS through the northbound
database.
Summary:
Configuration:
ip string
protocol optional string, either tcp or udp
port integer, in range 0 to 65,535
logical_port string
src_mac string
src_ip string
chassis_name string
options : interval optional string, containing an
integer
options : timeout optional string, containing an
integer
options : success_count optional string, containing an
integer
options : failure_count optional string, containing an
integer
Status Reporting:
status optional string, one of error,
offline, or online
Common Columns:
external_ids map of string-string pairs
Details:
Configuration:
ovn-northd sets these columns and values to configure the service
monitor.
ip: string
IP of the service to be monitored. Only IPv4 is supported.
protocol: optional string, either tcp or udp
The protocol of the service.
port: integer, in range 0 to 65,535
The TCP or UDP port of the service.
logical_port: string
The VIF of the logical port on which the service is
running. The ovn-controller that binds this logical_port
monitors the service by sending periodic monitor packets.
src_mac: string
Source Ethernet address to use in the service monitor
packet.
src_ip: string
Source IPv4 or IPv6 address to use in the service monitor
packet.
chassis_name: string
The name of the chassis where the logical port is bound.
options : interval: optional string, containing an integer
The interval, in seconds, between service monitor checks.
options : timeout: optional string, containing an integer
The time, in seconds, after which the service monitor
check times out.
options : success_count: optional string, containing an integer
The number of successful checks after which the service is
considered online.
options : failure_count: optional string, containing an integer
The number of failure checks after which the service is
considered offline.
Status Reporting:
The ovn-controller on the chassis that hosts the logical_port
updates this column to report the service’s status.
status: optional string, one of error, offline, or online
For TCP service, ovn-controller sends a SYN to the service
and expects an ACK response to consider the service to be
online.
For UDP service, ovn-controller sends a UDP packet to the
service and doesn’t expect any reply. If it receives an
ICMP reply, then it considers the service to be offline.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Each row represents a load balancer.
Summary:
name string
vips map of string-string pairs
protocol optional string, one of sctp, tcp,
or udp
datapaths set of Datapath_Bindings
datapath_group optional Logical_DP_Group
ls_datapath_group optional Logical_DP_Group
lr_datapath_group optional Logical_DP_Group
Load_Balancer options:
options : hairpin_snat_ip optional string
options : hairpin_orig_tuple
optional string, either true or
false
Common Columns:
external_ids map of string-string pairs
Details:
name: string
A name for the load balancer. This name has no special
meaning or purpose other than to provide convenience for
human interaction with the ovn-nb database.
vips: map of string-string pairs
A map of virtual IP addresses (and an optional port number
with : as a separator) associated with this load balancer
and their corresponding endpoint IP addresses (and
optional port numbers with : as separators) separated by
commas.
protocol: optional string, one of sctp, tcp, or udp
Valid protocols are tcp, udp, or sctp. This column is
useful when a port number is provided as part of the vips
column. If this column is empty and a port number is
provided as part of vips column, OVN assumes the protocol
to be tcp.
datapaths: set of Datapath_Bindings
Datapaths to which this load balancer applies to.
datapath_group: optional Logical_DP_Group
Deprecated. The group of datapaths to which this load
balancer applies to. This means that the same load
balancer applies to all datapaths in a group.
ls_datapath_group: optional Logical_DP_Group
The group of datapaths to which this load balancer applies
to. This means that the same load balancer applies to all
datapaths in a group.
lr_datapath_group: optional Logical_DP_Group
The group of logical router datapaths to which this load
balancer applies to. This means that the same load
balancer applies to all datapaths in a group.
Load_Balancer options:
options : hairpin_snat_ip: optional string
IP to be used as source IP for packets that have been
hair-pinned after load balancing. This value is
automatically populated by ovn-northd.
options : hairpin_orig_tuple: optional string, either true or
false
This value is automatically set to true by ovn-northd when
original destination IP and transport port of the load
balanced packets are stored in registers reg1, reg2,
xxreg1.
Common Columns:
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Contains BFD parameter for ovn-controller bfd configuration.
Summary:
Configuration:
src_port integer, in range 49,152 to 65,535
disc integer
logical_port string
dst_ip string
min_tx integer
min_rx integer
detect_mult integer
chassis_name string
options map of string-string pairs
external_ids map of string-string pairs
Status Reporting:
status string, one of admin_down, down,
init, or up
Details:
Configuration:
src_port: integer, in range 49,152 to 65,535
udp source port used in bfd control packets. The source
port MUST be in the range 49152 through 65535 (RFC5881
section 4).
disc: integer
A unique, nonzero discriminator value generated by the
transmitting system, used to demultiplex multiple BFD
sessions between the same pair of systems.
logical_port: string
OVN logical port when BFD engine is running.
dst_ip: string
BFD peer IP address.
min_tx: integer
This is the minimum interval, in milliseconds, that the
local system would like to use when transmitting BFD
Control packets, less any jitter applied. The value zero
is reserved.
min_rx: integer
This is the minimum interval, in milliseconds, between
received BFD Control packets that this system is capable
of supporting, less any jitter applied by the sender. If
this value is zero, the transmitting system does not want
the remote system to send any periodic BFD Control
packets.
detect_mult: integer
Detection time multiplier. The negotiated transmit
interval, multiplied by this value, provides the Detection
Time for the receiving system in Asynchronous mode.
chassis_name: string
The name of the chassis where the logical port is bound.
options: map of string-string pairs
Reserved for future use.
external_ids: map of string-string pairs
See External IDs at the beginning of this document.
Status Reporting:
status: string, one of admin_down, down, init, or up
BFD port logical states. Possible values are:
• admin_down
• down
• init
• up
This table is primarily used to learn the MACs observed on a VIF
(or a localnet port with ’localnet_learn_fdb’ enabled) which
belongs to a Logical_Switch_Port record in OVN_Northbound whose
port security is disabled and ’unknown’ address set. If port
security is disabled on a Logical_Switch_Port record, OVN should
allow traffic with any source mac from the VIF. This table will
be used to deliver a packet to the VIF, If a packet’s eth.dst is
learnt.
Summary:
mac string
dp_key integer, in range 1 to 16,777,215
port_key integer, in range 1 to 16,777,215
timestamp integer
Details:
mac: string
The learnt mac address.
dp_key: integer, in range 1 to 16,777,215
The key of the datapath on which this FDB was learnt.
port_key: integer, in range 1 to 16,777,215
The key of the port binding on which this FDB was learnt.
timestamp: integer
The timestamp in msec when the FDB was added or updated.
Records that existed before this column will have 0.
Each record represents a Static_MAC_Binding entry for a logical
router.
Summary:
logical_port string
ip string
mac string
override_dynamic_mac boolean
datapath Datapath_Binding
Details:
logical_port: string
The logical router port for the binding.
ip: string
The bound IP address.
mac: string
The Ethernet address to which the IP is bound.
override_dynamic_mac: boolean
Override dynamically learnt MACs.
datapath: Datapath_Binding
The logical datapath to which the logical router port
belongs.
Each record represents the set of template variable
instantiations for a given chassis and is populated by ovn-northd
from the contents of the OVN_Northbound.Chassis_Template_Var
table.
Summary:
chassis string (must be unique within
table)
variables map of string-string pairs
Details:
chassis: string (must be unique within table)
The chassis this set of variable values applies to.
variables: map of string-string pairs
The set of variable values for a given chassis.
This page is part of the Open Virtual Network (Daemons for Open
vSwitch that translate virtual network configurations into
OpenFlow) project. Information about the project can be found at
⟨https://www.ovn.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/ovn-org/ovn⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-12.) 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 24.03.90 DB Schema 20.34.0 ovn-sb(5)
Pages that refer to this page: ovn-sim(1), ovn-architecture(7), ovsdb(7), ovn-controller(8), ovn-controller-vtep(8), ovn-northd(8), ovn-sbctl(8), ovn-trace(8)
|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|