1 <?xml version="1.0" encoding="utf-8"?>
2 <database title="Open vSwitch Configuration Database">
4 A database with this schema holds the configuration for one Open
5 vSwitch daemon. The top-level configuration for the daemon is the
6 <ref table="Open_vSwitch"/> table, which must have exactly one
7 record. Records in other tables are significant only when they
8 can be reached directly or indirectly from the <ref
9 table="Open_vSwitch"/> table. Records that are not reachable from
10 the <ref table="Open_vSwitch"/> table are automatically deleted
11 from the database, except for records in a few distinguished
12 ``root set'' tables noted below.
15 <table name="Open_vSwitch" title="Open vSwitch configuration.">
16 Configuration for an Open vSwitch daemon. There must be exactly
17 one record in the <ref table="Open_vSwitch"/> table.
19 <group title="Configuration">
20 <column name="bridges">
21 Set of bridges managed by the daemon.
25 SSL used globally by the daemon.
28 <column name="other_config">
29 Key-value pairs for configuring rarely used Open vSwitch features. The
30 currently defined key-value pairs are:
32 <dt><code>enable-statistics</code></dt>
34 Set to <code>true</code> to enable populating the <ref
35 column="statistics"/> column or <code>false</code> (the default)
36 disable populating it.
41 <column name="external_ids">
42 Key-value pairs for use by external frameworks that integrate
43 with Open vSwitch, rather than by Open vSwitch itself. System
44 integrators should either use the Open vSwitch development
45 mailing list to coordinate on common key-value definitions, or
46 choose key names that are likely to be unique. The currently
47 defined common key-value pairs are:
49 <dt><code>system-id</code></dt>
50 <dd>A unique identifier for the Open vSwitch's physical host.
51 The form of the identifier depends on the type of the host.
52 On a Citrix XenServer, this will likely be the same as
53 <ref column="external_ids" key="xs-system-uuid"/>.</dd>
54 <dt><code>xs-system-uuid</code></dt>
55 <dd>The Citrix XenServer universally unique identifier for the
56 physical host as displayed by <code>xe host-list</code>.</dd>
61 <group title="Status">
62 <column name="next_cfg">
63 Sequence number for client to increment. When a client modifies
64 any part of the database configuration and wishes to wait for
65 Open vSwitch to finish applying the changes, it may increment
69 <column name="cur_cfg">
70 Sequence number that Open vSwitch sets to the current value of
71 <ref column="next_cfg"/> after it finishes applying a set of
72 configuration changes.
75 <column name="capabilities">
76 Describes functionality supported by the hardware and software platform
77 on which this Open vSwitch is based. Clients should not modify this
78 column. See the <ref table="Capability"/> description for defined
79 capability categories and the meaning of associated
80 <ref table="Capability"/> records.
83 <column name="statistics">
85 Key-value pairs that report statistics about a system running an Open
86 vSwitch. These are updated periodically (currently, every 5
87 seconds). Key-value pairs that cannot be determined or that do not
88 apply to a platform are omitted.
92 Statistics are disabled unless <ref column="other-config"
93 key="enable-statistics"/> is set to <code>true</code>.
97 <dt><code>cpu</code></dt>
100 Number of CPU processors, threads, or cores currently online and
101 available to the operating system on which Open vSwitch is
102 running, as an integer. This may be less than the number
103 installed, if some are not online or if they are not available to
104 the operating system.
107 Open vSwitch userspace processes are not multithreaded, but the
108 Linux kernel-based datapath is.
112 <dt><code>load_average</code></dt>
115 A comma-separated list of three floating-point numbers,
116 representing the system load average over the last 1, 5, and 15
117 minutes, respectively.
121 <dt><code>memory</code></dt>
124 A comma-separated list of integers, each of which represents a
125 quantity of memory in kilobytes that describes the operating
126 system on which Open vSwitch is running. In respective order,
131 <li>Total amount of RAM allocated to the OS.</li>
132 <li>RAM allocated to the OS that is in use.</li>
133 <li>RAM that can be flushed out to disk or otherwise discarded
134 if that space is needed for another purpose. This number is
135 necessarily less than or equal to the previous value.</li>
136 <li>Total disk space allocated for swap.</li>
137 <li>Swap space currently in use.</li>
141 On Linux, all five values can be determined and are included. On
142 other operating systems, only the first two values can be
143 determined, so the list will only have two values.
147 <dt><code>process_</code><var>name</var></dt>
150 One such key-value pair will exist for each running Open vSwitch
151 daemon process, with <var>name</var> replaced by the daemon's
152 name (e.g. <code>process_ovs-vswitchd</code>). The value is a
153 comma-separated list of integers. The integers represent the
154 following, with memory measured in kilobytes and durations in
159 <li>The process's virtual memory size.</li>
160 <li>The process's resident set size.</li>
161 <li>The amount of user and system CPU time consumed by the
163 <li>The number of times that the process has crashed and been
164 automatically restarted by the monitor.</li>
165 <li>The duration since the process was started.</li>
166 <li>The duration for which the process has been running.</li>
170 The interpretation of some of these values depends on whether the
171 process was started with the <option>--monitor</option>. If it
172 was not, then the crash count will always be 0 and the two
173 durations will always be the same. If <option>--monitor</option>
174 was given, then the crash count may be positive; if it is, the
175 latter duration is the amount of time since the most recent crash
180 There will be one key-value pair for each file in Open vSwitch's
181 ``run directory'' (usually <code>/var/run/openvswitch</code>)
182 whose name ends in <code>.pid</code>, whose contents are a
183 process ID, and which is locked by a running process. The
184 <var>name</var> is taken from the pidfile's name.
188 Currently Open vSwitch is only able to obtain all of the above
189 detail on Linux systems. On other systems, the same key-value
190 pairs will be present but the values will always be the empty
195 <dt><code>file_systems</code></dt>
198 A space-separated list of information on local, writable file
199 systems. Each item in the list describes one file system and
200 consists in turn of a comma-separated list of the following:
204 <li>Mount point, e.g. <code>/</code> or <code>/var/log</code>.
205 Any spaces or commas in the mount point are replaced by
207 <li>Total size, in kilobytes, as an integer.</li>
208 <li>Amount of storage in use, in kilobytes, as an integer.</li>
212 This key-value pair is omitted if there are no local, writable
213 file systems or if Open vSwitch cannot obtain the needed
221 <group title="Version Reporting">
223 These columns report the types and versions of the hardware and
224 software running Open vSwitch. We recommend in general that software
225 should test whether specific features are supported instead of relying
226 on version number checks. These values are primarily intended for
227 reporting to human administrators.
230 <column name="ovs_version">
231 The Open vSwitch version number, e.g. <code>1.1.0</code>.
232 If Open vSwitch was configured with a build number, then it is
233 also included, e.g. <code>1.1.0+build6579</code>.
236 <column name="db_version">
238 The database schema version number in the form
239 <code><var>major</var>.<var>minor</var>.<var>tweak</var></code>,
240 e.g. <code>1.2.3</code>. Whenever the database schema is changed in
241 a non-backward compatible way (e.g. deleting a column or a table),
242 <var>major</var> is incremented. When the database schema is changed
243 in a backward compatible way (e.g. adding a new column),
244 <var>minor</var> is incremented. When the database schema is changed
245 cosmetically (e.g. reindenting its syntax), <var>tweak</var> is
250 The schema version is part of the database schema, so it can also be
251 retrieved by fetching the schema using the Open vSwitch database
256 <column name="system_type">
258 An identifier for the type of system on top of which Open vSwitch
259 runs, e.g. <code>XenServer</code> or <code>KVM</code>.
262 System integrators are responsible for choosing and setting an
263 appropriate value for this column.
267 <column name="system_version">
269 The version of the system identified by <ref column="system_type"/>,
270 e.g. <code>5.6.100-39265p</code> on XenServer 5.6.100 build 39265.
273 System integrators are responsible for choosing and setting an
274 appropriate value for this column.
280 <group title="Database Configuration">
282 These columns primarily configure the Open vSwitch database
283 (<code>ovsdb-server</code>), not the Open vSwitch switch
284 (<code>ovs-vswitchd</code>). The OVSDB database also uses the <ref
285 column="ssl"/> settings.
289 The Open vSwitch switch does read the database configuration to
290 determine remote IP addresses to which in-band control should apply.
293 <column name="manager_options">
294 Database clients to which the Open vSwitch database server should
295 connect or to which it should listen, along with options for how these
296 connection should be configured. See the <ref table="Manager"/> table
297 for more information.
302 <table name="Bridge">
304 Configuration for a bridge within an
305 <ref table="Open_vSwitch"/>.
308 A <ref table="Bridge"/> record represents an Ethernet switch with one or
309 more ``ports,'' which are the <ref table="Port"/> records pointed to by
310 the <ref table="Bridge"/>'s <ref column="ports"/> column.
313 <group title="Core Features">
315 Bridge identifier. Should be alphanumeric and no more than about 8
316 bytes long. Must be unique among the names of ports, interfaces, and
320 <column name="ports">
321 Ports included in the bridge.
324 <column name="mirrors">
325 Port mirroring configuration.
328 <column name="netflow">
329 NetFlow configuration.
332 <column name="sflow">
336 <column name="flood_vlans">
337 VLAN IDs of VLANs on which MAC address learning should be disabled, so
338 that packets are flooded instead of being sent to specific ports that
339 are believed to contain packets' destination MACs. This should
340 ordinarily be used to disable MAC learning on VLANs used for mirroring
341 (RSPAN VLANs). It may also be useful for debugging.
345 <group title="OpenFlow Configuration">
346 <column name="controller">
347 OpenFlow controller set. If unset, then no OpenFlow controllers
351 <column name="fail_mode">
352 <p>When a controller is configured, it is, ordinarily, responsible
353 for setting up all flows on the switch. Thus, if the connection to
354 the controller fails, no new network connections can be set up.
355 If the connection to the controller stays down long enough,
356 no packets can pass through the switch at all. This setting
357 determines the switch's response to such a situation. It may be set
358 to one of the following:
360 <dt><code>standalone</code></dt>
361 <dd>If no message is received from the controller for three
362 times the inactivity probe interval
363 (see <ref column="inactivity_probe"/>), then Open vSwitch
364 will take over responsibility for setting up flows. In
365 this mode, Open vSwitch causes the bridge to act like an
366 ordinary MAC-learning switch. Open vSwitch will continue
367 to retry connecting to the controller in the background
368 and, when the connection succeeds, it will discontinue its
369 standalone behavior.</dd>
370 <dt><code>secure</code></dt>
371 <dd>Open vSwitch will not set up flows on its own when the
372 controller connection fails or when no controllers are
373 defined. The bridge will continue to retry connecting to
374 any defined controllers forever.</dd>
377 <p>If this value is unset, the default is implementation-specific.</p>
378 <p>When more than one controller is configured,
379 <ref column="fail_mode"/> is considered only when none of the
380 configured controllers can be contacted.</p>
383 <column name="datapath_id">
384 Reports the OpenFlow datapath ID in use. Exactly 16 hex digits.
385 (Setting this column has no useful effect. Set <ref
386 column="other-config" key="datapath-id"/> instead.)
390 <group title="Other Features">
391 <column name="datapath_type">
392 Name of datapath provider. The kernel datapath has
393 type <code>system</code>. The userspace datapath has
394 type <code>netdev</code>.
397 <column name="external_ids">
398 Key-value pairs for use by external frameworks that integrate
399 with Open vSwitch, rather than by Open vSwitch itself. System
400 integrators should either use the Open vSwitch development
401 mailing list to coordinate on common key-value definitions, or
402 choose key names that are likely to be unique. The currently
403 defined key-value pairs are:
405 <dt><code>bridge-id</code></dt>
406 <dd>A unique identifier of the bridge. On Citrix XenServer this will
407 commonly be the same as
408 <ref column="external_ids" key="xs-network-uuids"/>.</dd>
409 <dt><code>xs-network-uuids</code></dt>
410 <dd>Semicolon-delimited set of universally unique identifier(s) for
411 the network with which this bridge is associated on a Citrix
412 XenServer host. The network identifiers are RFC 4122 UUIDs as
413 displayed by, e.g., <code>xe network-list</code>.</dd>
417 <column name="other_config">
418 Key-value pairs for configuring rarely used bridge
419 features. The currently defined key-value pairs are:
421 <dt><code>datapath-id</code></dt>
423 digits to set the OpenFlow datapath ID to a specific
424 value. May not be all-zero.</dd>
425 <dt><code>disable-in-band</code></dt>
426 <dd>If set to <code>true</code>, disable in-band control on
427 the bridge regardless of controller and manager settings.</dd>
428 <dt><code>hwaddr</code></dt>
429 <dd>An Ethernet address in the form
430 <var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>
431 to set the hardware address of the local port and influence the
433 <dt><code>in-band-queue</code></dt>
435 A queue ID as a nonnegative integer. This sets the OpenFlow queue
436 ID that will be used by flows set up by in-band control on this
437 bridge. If unset, or if the port used by an in-band control flow
438 does not have QoS configured, or if the port does not have a queue
439 with the specified ID, the default queue is used instead.
441 <dt><code>flow-eviction-threshold</code></dt>
443 A number of flows as a nonnegative integer. This sets number
444 of flows at which eviction from the kernel flow table will
446 If there are a large number of flows then increasing this
447 value to around the number of flows present
448 can result in reduced CPU usage and packet loss.
454 Values below 100 will be rounded up to 100.
461 <table name="Port" table="Port or bond configuration.">
462 <p>A port within a <ref table="Bridge"/>.</p>
463 <p>Most commonly, a port has exactly one ``interface,'' pointed to by its
464 <ref column="interfaces"/> column. Such a port logically
465 corresponds to a port on a physical Ethernet switch. A port
466 with more than one interface is a ``bonded port'' (see
467 <ref group="Bonding Configuration"/>).</p>
468 <p>Some properties that one might think as belonging to a port are actually
469 part of the port's <ref table="Interface"/> members.</p>
472 Port name. Should be alphanumeric and no more than about 8
473 bytes long. May be the same as the interface name, for
474 non-bonded ports. Must otherwise be unique among the names of
475 ports, interfaces, and bridges on a host.
478 <column name="interfaces">
479 The port's interfaces. If there is more than one, this is a
483 <group title="VLAN Configuration">
484 <p>A bridge port must be configured for VLANs in one of two
485 mutually exclusive ways:
487 <li>A ``trunk port'' has an empty value for <ref
488 column="tag"/>. Its <ref column="trunks"/> value may be
489 empty or non-empty.</li>
490 <li>An ``implicitly tagged VLAN port'' or ``access port''
491 has an nonempty value for <ref column="tag"/>. Its
492 <ref column="trunks"/> value must be empty.</li>
494 If <ref column="trunks"/> and <ref column="tag"/> are both
495 nonempty, the configuration is ill-formed.
500 If this is an access port (see above), the port's implicitly
501 tagged VLAN. Must be empty if this is a trunk port.
504 Frames arriving on trunk ports will be forwarded to this
505 port only if they are tagged with the given VLAN (or, if
506 <ref column="tag"/> is 0, then if they lack a VLAN header).
507 Frames arriving on other access ports will be forwarded to
508 this port only if they have the same <ref column="tag"/>
509 value. Frames forwarded to this port will not have an
513 When a frame with a 802.1Q header that indicates a nonzero
514 VLAN is received on an access port, it is discarded.
518 <column name="trunks">
520 If this is a trunk port (see above), the 802.1Q VLAN(s) that
521 this port trunks; if it is empty, then the port trunks all
522 VLANs. Must be empty if this is an access port.
525 Frames arriving on trunk ports are dropped if they are not
526 in one of the specified VLANs. For this purpose, packets
527 that have no VLAN header are treated as part of VLAN 0.
532 <group title="Bonding Configuration">
533 <p>A port that has more than one interface is a ``bonded port.'' Bonding
534 allows for load balancing and fail-over. Some kinds of bonding will
535 work with any kind of upstream switch:</p>
538 <dt><code>balance-slb</code></dt>
540 Balances flows among slaves based on source MAC address and output
541 VLAN, with periodic rebalancing as traffic patterns change.
544 <dt><code>active-backup</code></dt>
546 Assigns all flows to one slave, failing over to a backup slave when
547 the active slave is disabled.
552 The following modes require the upstream switch to support 802.3ad with
553 successful LACP negotiation. If LACP negotiation fails then
554 <code>balance-slb</code> style flow hashing is used as a fallback:
558 <dt><code>balance-tcp</code></dt>
560 Balances flows among slaves based on L2, L3, and L4 protocol
561 information such as destination MAC address, IP address, and TCP
567 <dt><code>stable</code></dt>
569 <p>Attempts to always assign a given flow to the same slave
570 consistently. In an effort to maintain stability, no load
571 balancing is done. Uses a similar hashing strategy to
572 <code>balance-tcp</code>, always taking into account L3 and L4
573 fields even if LACP negotiations are unsuccessful. </p>
574 <p>Slave selection decisions are made based on <ref table="Interface"
575 column="other_config" key="bond-stable-id"/> if set. Otherwise,
576 OpenFlow port number is used. Decisions are consistent across all
577 <code>ovs-vswitchd</code> instances with equivalent
578 <ref table="Interface" column="other_config" key="bond-stable-id"/>
583 <p>These columns apply only to bonded ports. Their values are
584 otherwise ignored.</p>
586 <column name="bond_mode">
587 <p>The type of bonding used for a bonded port. Defaults to
588 <code>balance-slb</code> if unset.
592 <column name="bond_updelay">
593 <p>For a bonded port, the number of milliseconds for which carrier must
594 stay up on an interface before the interface is considered to be up.
595 Specify <code>0</code> to enable the interface immediately.</p>
596 <p>This setting is honored only when at least one bonded interface is
597 already enabled. When no interfaces are enabled, then the first bond
598 interface to come up is enabled immediately.</p>
601 <column name="bond_downdelay">
602 For a bonded port, the number of milliseconds for which carrier must
603 stay down on an interface before the interface is considered to be
604 down. Specify <code>0</code> to disable the interface immediately.
607 <column name="bond_fake_iface">
608 For a bonded port, whether to create a fake internal interface with the
609 name of the port. Use only for compatibility with legacy software that
614 <p>Configures LACP on this port. LACP allows directly connected
615 switches to negotiate which links may be bonded. LACP may be enabled
616 on non-bonded ports for the benefit of any switches they may be
617 connected to. <code>active</code> ports are allowed to initiate LACP
618 negotiations. <code>passive</code> ports are allowed to participate
619 in LACP negotiations initiated by a remote switch, but not allowed to
620 initiate such negotiations themselves. If unset Open vSwitch will
621 choose a reasonable default. </p>
626 <group title="Other Features">
628 Quality of Service configuration for this port.
632 The MAC address to use for this port for the purpose of choosing the
633 bridge's MAC address. This column does not necessarily reflect the
634 port's actual MAC address, nor will setting it change the port's actual
638 <column name="fake_bridge">
639 Does this port represent a sub-bridge for its tagged VLAN within the
640 Bridge? See ovs-vsctl(8) for more information.
643 <column name="external_ids">
645 Key-value pairs for use by external frameworks that integrate with
646 Open vSwitch, rather than by Open vSwitch itself. System integrators
647 should either use the Open vSwitch development mailing list to
648 coordinate on common key-value definitions, or choose key names that
649 are likely to be unique.
652 No key-value pairs native to <ref table="Port"/> are currently
653 defined. For fake bridges (see the <ref column="fake_bridge"/>
654 column), external IDs for the fake bridge are defined here by
655 prefixing a <ref table="Bridge"/> <ref table="Bridge"
656 column="external_ids"/> key with <code>fake-bridge-</code>,
657 e.g. <code>fake-bridge-xs-network-uuids</code>.
661 <column name="other_config">
662 Key-value pairs for configuring rarely used port features. The
663 currently defined key-value pairs are:
665 <dt><code>hwaddr</code></dt>
666 <dd>An Ethernet address in the form
667 <code><var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var></code>.</dd>
668 <dt><code>bond-rebalance-interval</code></dt>
669 <dd>For an SLB bonded port, the number of milliseconds between
670 successive attempts to rebalance the bond, that is, to
671 move source MACs and their flows from one interface on
672 the bond to another in an attempt to keep usage of each
673 interface roughly equal. The default is 10000 (10
674 seconds), and the minimum is 1000 (1 second).</dd>
675 <dt><code>bond-detect-mode</code></dt>
676 <dd> Sets the method used to detect link failures in a bonded port.
677 Options are <code>carrier</code> and <code>miimon</code>. Defaults
678 to <code>carrier</code> which uses each interface's carrier to detect
679 failures. When set to <code>miimon</code>, will check for failures
680 by polling each interface's MII. </dd>
681 <dt><code>bond-miimon-interval</code></dt>
682 <dd> The number of milliseconds between successive attempts to
683 poll each interface's MII. Only relevant on ports which use
684 <code>miimon</code> to detect failures. </dd>
685 <dt><code>bond-hash-basis</code></dt>
686 <dd> An integer hashed along with flows when choosing output slaves.
687 When changed, all flows will be assigned different hash values
688 possibly causing slave selection decisions to change.</dd>
689 <dt><code>lacp-system-id</code></dt>
690 <dd> The LACP system ID of this <ref table="Port"/>. The system ID
691 of a LACP bond is used to identify itself to its partners. Must
692 be a nonzero MAC address.</dd>
693 <dt><code>lacp-system-priority</code></dt>
694 <dd> The LACP system priority of this <ref table="Port"/>. In
695 LACP negotiations, link status decisions are made by the system
696 with the numerically lower priority. Must be a number between 1
698 <dt><code>lacp-time</code></dt>
700 <p>The LACP timing which should be used on this
701 <ref table="Port"/>. Possible values are <code>fast</code>,
702 <code>slow</code> and a positive number of milliseconds. By
703 default <code>slow</code> is used. When configured to be
704 <code>fast</code> LACP heartbeats are requested at a rate of once
705 per second causing connectivity problems to be detected more
706 quickly. In <code>slow</code> mode, heartbeats are requested at
707 a rate of once every 30 seconds.</p>
709 <p>Users may manually set a heartbeat transmission rate to increase
710 the fault detection speed further. When manually set, OVS
711 expects the partner switch to be configured with the same
712 transmission rate. Manually setting <code>lacp-time</code> to
713 something other than <code>fast</code> or <code>slow</code> is
714 not supported by the LACP specification.</p>
716 <dt><code>lacp-heartbeat</code></dt>
717 <dd> Treats LACP like a simple heartbeat protocol for link state
718 monitoring. Most features of the LACP protocol are disabled when
719 this mode is in use.</dd>
725 <table name="Interface" title="One physical network device in a Port.">
726 An interface within a <ref table="Port"/>.
728 <group title="Core Features">
730 Interface name. Should be alphanumeric and no more than about 8 bytes
731 long. May be the same as the port name, for non-bonded ports. Must
732 otherwise be unique among the names of ports, interfaces, and bridges
737 <p>Ethernet address to set for this interface. If unset then the
738 default MAC address is used:</p>
740 <li>For the local interface, the default is the lowest-numbered MAC
741 address among the other bridge ports, either the value of the
742 <ref table="Port" column="mac"/> in its <ref table="Port"/> record,
743 if set, or its actual MAC (for bonded ports, the MAC of its slave
744 whose name is first in alphabetical order). Internal ports and
745 bridge ports that are used as port mirroring destinations (see the
746 <ref table="Mirror"/> table) are ignored.</li>
747 <li>For other internal interfaces, the default MAC is randomly
749 <li>External interfaces typically have a MAC address associated with
752 <p>Some interfaces may not have a software-controllable MAC
756 <column name="ofport">
757 <p>OpenFlow port number for this interface. Unlike most columns, this
758 column's value should be set only by Open vSwitch itself. Other
759 clients should set this column to an empty set (the default) when
760 creating an <ref table="Interface"/>.</p>
761 <p>Open vSwitch populates this column when the port number becomes
762 known. If the interface is successfully added,
763 <ref column="ofport"/> will be set to a number between 1 and 65535
764 (generally either in the range 1 to 65279, inclusive, or 65534, the
765 port number for the OpenFlow ``local port''). If the interface
766 cannot be added then Open vSwitch sets this column
771 <group title="System-Specific Details">
773 The interface type, one of:
775 <dt><code>system</code></dt>
776 <dd>An ordinary network device, e.g. <code>eth0</code> on Linux.
777 Sometimes referred to as ``external interfaces'' since they are
778 generally connected to hardware external to that on which the Open
779 vSwitch is running. The empty string is a synonym for
780 <code>system</code>.</dd>
781 <dt><code>internal</code></dt>
782 <dd>A simulated network device that sends and receives traffic. An
783 internal interface whose <ref column="name"/> is the same as its
784 bridge's <ref table="Open_vSwitch" column="name"/> is called the
785 ``local interface.'' It does not make sense to bond an internal
786 interface, so the terms ``port'' and ``interface'' are often used
787 imprecisely for internal interfaces.</dd>
788 <dt><code>tap</code></dt>
789 <dd>A TUN/TAP device managed by Open vSwitch.</dd>
790 <dt><code>gre</code></dt>
791 <dd>An Ethernet over RFC 2890 Generic Routing Encapsulation over IPv4
792 tunnel. Each tunnel must be uniquely identified by the
793 combination of <ref column="options" key="remote_ip"/>,
794 <ref column="options" key="local_ip"/>, and
795 <ref column="options" key="in_key"/>. Note that if two ports
796 are defined that are the same except one has an optional
797 identifier and the other does not, the more specific one is
798 matched first. <ref column="options" key="in_key"/> is considered
799 more specific than <ref column="options" key="local_ip"/> if a port
800 defines one and another port defines the other. The following
801 options may be specified in the <ref column="options"/> column:
803 <dt><code>remote_ip</code></dt>
804 <dd>Required. The tunnel endpoint.</dd>
807 <dt><code>local_ip</code></dt>
808 <dd>Optional. The destination IP that received packets must
809 match. Default is to match all addresses.</dd>
812 <dt><code>in_key</code></dt>
813 <dd>Optional. The GRE key that received packets must contain.
814 It may either be a 32-bit number (no key and a key of 0 are
815 treated as equivalent) or the word <code>flow</code>. If
816 <code>flow</code> is specified then any key will be accepted
817 and the key will be placed in the <code>tun_id</code> field
818 for matching in the flow table. The ovs-ofctl manual page
819 contains additional information about matching fields in
820 OpenFlow flows. Default is no key.</dd>
823 <dt><code>out_key</code></dt>
824 <dd>Optional. The GRE key to be set on outgoing packets. It may
825 either be a 32-bit number or the word <code>flow</code>. If
826 <code>flow</code> is specified then the key may be set using
827 the <code>set_tunnel</code> Nicira OpenFlow vendor extension (0
828 is used in the absence of an action). The ovs-ofctl manual
829 page contains additional information about the Nicira OpenFlow
830 vendor extensions. Default is no key.</dd>
833 <dt><code>key</code></dt>
834 <dd>Optional. Shorthand to set <code>in_key</code> and
835 <code>out_key</code> at the same time.</dd>
838 <dt><code>tos</code></dt>
839 <dd>Optional. The value of the ToS bits to be set on the
840 encapsulating packet. It may also be the word
841 <code>inherit</code>, in which case the ToS will be copied from
842 the inner packet if it is IPv4 or IPv6 (otherwise it will be
843 0). Note that the ECN fields are always inherited. Default is
847 <dt><code>ttl</code></dt>
848 <dd>Optional. The TTL to be set on the encapsulating packet.
849 It may also be the word <code>inherit</code>, in which case the
850 TTL will be copied from the inner packet if it is IPv4 or IPv6
851 (otherwise it will be the system default, typically 64).
852 Default is the system default TTL.</dd>
855 <dt><code>csum</code></dt>
856 <dd>Optional. Compute GRE checksums on outgoing packets.
857 Checksums present on incoming packets will be validated
858 regardless of this setting. Note that GRE checksums
859 impose a significant performance penalty as they cover the
860 entire packet. As the contents of the packet is typically
861 covered by L3 and L4 checksums, this additional checksum only
862 adds value for the GRE and encapsulated Ethernet headers.
863 Default is disabled, set to <code>true</code> to enable.</dd>
866 <dt><code>df_inherit</code></dt>
867 <dd>Optional. If enabled, the Don't Fragment bit will be copied
868 from the inner IP headers (those of the encapsulated traffic)
869 to the outer (tunnel) headers. Default is disabled; set to
870 <code>true</code> to enable.</dd>
873 <dt><code>df_default</code></dt>
874 <dd>Optional. If enabled, the Don't Fragment bit will be set by
875 default on tunnel headers if the <code>df_inherit</code> option
876 is not set, or if the encapsulated packet is not IP. Default
877 is enabled; set to <code>false</code> to disable.</dd>
880 <dt><code>pmtud</code></dt>
881 <dd>Optional. Enable tunnel path MTU discovery. If enabled
882 ``ICMP Destination Unreachable - Fragmentation Needed''
883 messages will be generated for IPv4 packets with the DF bit set
884 and IPv6 packets above the minimum MTU if the packet size
885 exceeds the path MTU minus the size of the tunnel headers.
886 Note that this option causes behavior that is typically
887 reserved for routers and therefore is not entirely in
888 compliance with the IEEE 802.1D specification for bridges.
889 Default is enabled; set to <code>false</code> to disable.</dd>
892 <dt><code>header_cache</code></dt>
893 <dd>Optional. Enable caching of tunnel headers and the output
894 path. This can lead to a significant performance increase
895 without changing behavior. In general it should not be
896 necessary to adjust this setting. However, the caching can
897 bypass certain components of the IP stack (such as IP tables)
898 and it may be useful to disable it if these features are
899 required or as a debugging measure. Default is enabled, set to
900 <code>false</code> to disable.</dd>
903 <dt><code>ipsec_gre</code></dt>
904 <dd>An Ethernet over RFC 2890 Generic Routing Encapsulation
905 over IPv4 IPsec tunnel. Each tunnel (including those of type
906 <code>gre</code>) must be uniquely identified by the
907 combination of <ref column="options" key="remote_ip"/> and
908 <ref column="options" key="local_ip"/>. Note that if two ports are
909 defined that are the same except one has an optional identifier and
910 the other does not, the more specific one is matched first.
911 An authentication method of <ref column="options" key="peer_cert"/>
912 or <ref column="options" key="psk"/> must be defined. The
913 following options may be specified in the <ref column="options"/>
916 <dt><code>remote_ip</code></dt>
917 <dd>Required. The tunnel endpoint.</dd>
920 <dt><code>local_ip</code></dt>
921 <dd>Optional. The destination IP that received packets must
922 match. Default is to match all addresses.</dd>
925 <dt><code>peer_cert</code></dt>
926 <dd>Required for certificate authentication. A string
927 containing the peer's certificate in PEM format.
928 Additionally the host's certificate must be specified
929 with the <code>certificate</code> option.</dd>
932 <dt><code>certificate</code></dt>
933 <dd>Required for certificate authentication. The name of a
934 PEM file containing a certificate that will be presented
935 to the peer during authentication.</dd>
938 <dt><code>private_key</code></dt>
939 <dd>Optional for certificate authentication. The name of
940 a PEM file containing the private key associated with
941 <code>certificate</code>. If <code>certificate</code>
942 contains the private key, this option may be omitted.</dd>
945 <dt><code>psk</code></dt>
946 <dd>Required for pre-shared key authentication. Specifies a
947 pre-shared key for authentication that must be identical on
948 both sides of the tunnel.</dd>
951 <dt><code>in_key</code></dt>
952 <dd>Optional. The GRE key that received packets must contain.
953 It may either be a 32-bit number (no key and a key of 0 are
954 treated as equivalent) or the word <code>flow</code>. If
955 <code>flow</code> is specified then any key will be accepted
956 and the key will be placed in the <code>tun_id</code> field
957 for matching in the flow table. The ovs-ofctl manual page
958 contains additional information about matching fields in
959 OpenFlow flows. Default is no key.</dd>
962 <dt><code>out_key</code></dt>
963 <dd>Optional. The GRE key to be set on outgoing packets. It may
964 either be a 32-bit number or the word <code>flow</code>. If
965 <code>flow</code> is specified then the key may be set using
966 the <code>set_tunnel</code> Nicira OpenFlow vendor extension (0
967 is used in the absence of an action). The ovs-ofctl manual
968 page contains additional information about the Nicira OpenFlow
969 vendor extensions. Default is no key.</dd>
972 <dt><code>key</code></dt>
973 <dd>Optional. Shorthand to set <code>in_key</code> and
974 <code>out_key</code> at the same time.</dd>
977 <dt><code>tos</code></dt>
978 <dd>Optional. The value of the ToS bits to be set on the
979 encapsulating packet. It may also be the word
980 <code>inherit</code>, in which case the ToS will be copied from
981 the inner packet if it is IPv4 or IPv6 (otherwise it will be
982 0). Note that the ECN fields are always inherited. Default is
986 <dt><code>ttl</code></dt>
987 <dd>Optional. The TTL to be set on the encapsulating packet.
988 It may also be the word <code>inherit</code>, in which case the
989 TTL will be copied from the inner packet if it is IPv4 or IPv6
990 (otherwise it will be the system default, typically 64).
991 Default is the system default TTL.</dd>
994 <dt><code>csum</code></dt>
995 <dd>Optional. Compute GRE checksums on outgoing packets.
996 Checksums present on incoming packets will be validated
997 regardless of this setting. Note that GRE checksums
998 impose a significant performance penalty as they cover the
999 entire packet. As the contents of the packet is typically
1000 covered by L3 and L4 checksums, this additional checksum only
1001 adds value for the GRE and encapsulated Ethernet headers.
1002 Default is disabled, set to <code>true</code> to enable.</dd>
1005 <dt><code>df_inherit</code></dt>
1006 <dd>Optional. If enabled, the Don't Fragment bit will be copied
1007 from the inner IP headers (those of the encapsulated traffic)
1008 to the outer (tunnel) headers. Default is disabled; set to
1009 <code>true</code> to enable.</dd>
1012 <dt><code>df_default</code></dt>
1013 <dd>Optional. If enabled, the Don't Fragment bit will be set by
1014 default on tunnel headers if the <code>df_inherit</code> option
1015 is not set, or if the encapsulated packet is not IP. Default
1016 is enabled; set to <code>false</code> to disable.</dd>
1019 <dt><code>pmtud</code></dt>
1020 <dd>Optional. Enable tunnel path MTU discovery. If enabled
1021 ``ICMP Destination Unreachable - Fragmentation Needed''
1022 messages will be generated for IPv4 packets with the DF bit set
1023 and IPv6 packets above the minimum MTU if the packet size
1024 exceeds the path MTU minus the size of the tunnel headers.
1025 Note that this option causes behavior that is typically
1026 reserved for routers and therefore is not entirely in
1027 compliance with the IEEE 802.1D specification for bridges.
1028 Default is enabled; set to <code>false</code> to disable.</dd>
1031 <dt><code>capwap</code></dt>
1032 <dd>Ethernet tunneling over the UDP transport portion of CAPWAP
1033 (RFC 5415). This allows interoperability with certain switches
1034 where GRE is not available. Note that only the tunneling component
1035 of the protocol is implemented. Due to the non-standard use of
1036 CAPWAP, UDP ports 58881 and 58882 are used as the source and
1037 destination ports respectively. Each tunnel must be uniquely
1038 identified by the combination of
1039 <ref column="options" key="remote_ip"/> and
1040 <ref column="options" key="local_ip"/>. If two ports are defined
1041 that are the same except one includes
1042 <ref column="options" key="local_ip"/> and the other does not, the
1043 more specific one is matched first. CAPWAP support is not
1044 available on all platforms. Currently it is only supported in the
1045 Linux kernel module with kernel versions >= 2.6.25. The following
1046 options may be specified in the <ref column="options"/> column:
1048 <dt><code>remote_ip</code></dt>
1049 <dd>Required. The tunnel endpoint.</dd>
1052 <dt><code>local_ip</code></dt>
1053 <dd>Optional. The destination IP that received packets must
1054 match. Default is to match all addresses.</dd>
1057 <dt><code>tos</code></dt>
1058 <dd>Optional. The value of the ToS bits to be set on the
1059 encapsulating packet. It may also be the word
1060 <code>inherit</code>, in which case the ToS will be copied from
1061 the inner packet if it is IPv4 or IPv6 (otherwise it will be
1062 0). Note that the ECN fields are always inherited. Default is
1066 <dt><code>ttl</code></dt>
1067 <dd>Optional. The TTL to be set on the encapsulating packet.
1068 It may also be the word <code>inherit</code>, in which case the
1069 TTL will be copied from the inner packet if it is IPv4 or IPv6
1070 (otherwise it will be the system default, typically 64).
1071 Default is the system default TTL.</dd>
1074 <dt><code>df_inherit</code></dt>
1075 <dd>Optional. If enabled, the Don't Fragment bit will be copied
1076 from the inner IP headers (those of the encapsulated traffic)
1077 to the outer (tunnel) headers. Default is disabled; set to
1078 <code>true</code> to enable.</dd>
1081 <dt><code>df_default</code></dt>
1082 <dd>Optional. If enabled, the Don't Fragment bit will be set by
1083 default on tunnel headers if the <code>df_inherit</code> option
1084 is not set, or if the encapsulated packet is not IP. Default
1085 is enabled; set to <code>false</code> to disable.</dd>
1088 <dt><code>pmtud</code></dt>
1089 <dd>Optional. Enable tunnel path MTU discovery. If enabled
1090 ``ICMP Destination Unreachable - Fragmentation Needed''
1091 messages will be generated for IPv4 packets with the DF bit set
1092 and IPv6 packets above the minimum MTU if the packet size
1093 exceeds the path MTU minus the size of the tunnel headers.
1094 Note that this option causes behavior that is typically
1095 reserved for routers and therefore is not entirely in
1096 compliance with the IEEE 802.1D specification for bridges.
1097 Default is enabled; set to <code>false</code> to disable.</dd>
1100 <dt><code>header_cache</code></dt>
1101 <dd>Optional. Enable caching of tunnel headers and the output
1102 path. This can lead to a significant performance increase
1103 without changing behavior. In general it should not be
1104 necessary to adjust this setting. However, the caching can
1105 bypass certain components of the IP stack (such as IP tables)
1106 and it may be useful to disable it if these features are
1107 required or as a debugging measure. Default is enabled, set to
1108 <code>false</code> to disable.</dd>
1111 <dt><code>patch</code></dt>
1114 A pair of virtual devices that act as a patch cable. The <ref
1115 column="options"/> column must have the following key-value pair:
1118 <dt><code>peer</code></dt>
1120 The <ref column="name"/> of the <ref table="Interface"/> for
1121 the other side of the patch. The named <ref
1122 table="Interface"/>'s own <code>peer</code> option must specify
1123 this <ref table="Interface"/>'s name. That is, the two patch
1124 interfaces must have reversed <ref column="name"/> and
1125 <code>peer</code> values.
1129 <dt><code>null</code></dt>
1130 <dd>An ignored interface.</dd>
1134 <column name="options">
1135 Configuration options whose interpretation varies based on
1136 <ref column="type"/>.
1140 <group title="Interface Status">
1142 Status information about interfaces attached to bridges, updated every
1143 5 seconds. Not all interfaces have all of these properties; virtual
1144 interfaces don't have a link speed, for example. Non-applicable
1145 columns will have empty values.
1147 <column name="admin_state">
1149 The administrative state of the physical network link.
1153 <column name="link_state">
1155 The observed state of the physical network link. This is ordinarily
1156 the link's carrier status. If the interface's <ref table="Port"/> is
1157 a bond configured for miimon monitoring, it is instead the network
1158 link's miimon status.
1162 <column name="link_speed">
1164 The negotiated speed of the physical network link.
1165 Valid values are positive integers greater than 0.
1169 <column name="duplex">
1171 The duplex mode of the physical network link.
1177 The MTU (maximum transmission unit); i.e. the largest
1178 amount of data that can fit into a single Ethernet frame.
1179 The standard Ethernet MTU is 1500 bytes. Some physical media
1180 and many kinds of virtual interfaces can be configured with
1184 This column will be empty for an interface that does not
1185 have an MTU as, for example, some kinds of tunnels do not.
1189 <column name="status">
1191 Key-value pairs that report port status. Supported status values are
1192 <ref column="type"/>-dependent; some interfaces may not have a valid
1193 <ref column="status" key="driver_name"/>, for example.
1195 <p>The currently defined key-value pairs are:</p>
1197 <dt><code>driver_name</code></dt>
1198 <dd>The name of the device driver controlling the network
1202 <dt><code>driver_version</code></dt>
1203 <dd>The version string of the device driver controlling the
1204 network adapter.</dd>
1207 <dt><code>firmware_version</code></dt>
1208 <dd>The version string of the network adapter's firmware, if
1212 <dt><code>source_ip</code></dt>
1213 <dd>The source IP address used for an IPv4 tunnel end-point,
1214 such as <code>gre</code> or <code>capwap</code>.</dd>
1217 <dt><code>tunnel_egress_iface</code></dt>
1218 <dd>Egress interface for tunnels. Currently only relevant for GRE
1219 and CAPWAP tunnels. On Linux systems, this column will show
1220 the name of the interface which is responsible for routing
1221 traffic destined for the configured
1222 <ref column="options" key="remote_ip"/>. This could be an
1223 internal interface such as a bridge port.</dd>
1226 <dt><code>tunnel_egress_iface_carrier</code></dt>
1227 <dd>Whether a carrier is detected on
1228 <ref column="status" key="tunnel_egress_iface"/>. Valid values
1229 are <code>down</code> and <code>up</code>.</dd>
1234 <group title="Ingress Policing">
1236 These settings control ingress policing for packets received on this
1237 interface. On a physical interface, this limits the rate at which
1238 traffic is allowed into the system from the outside; on a virtual
1239 interface (one connected to a virtual machine), this limits the rate at
1240 which the VM is able to transmit.
1243 Policing is a simple form of quality-of-service that simply drops
1244 packets received in excess of the configured rate. Due to its
1245 simplicity, policing is usually less accurate and less effective than
1246 egress QoS (which is configured using the <ref table="QoS"/> and <ref
1247 table="Queue"/> tables).
1250 Policing is currently implemented only on Linux. The Linux
1251 implementation uses a simple ``token bucket'' approach:
1255 The size of the bucket corresponds to <ref
1256 column="ingress_policing_burst"/>. Initially the bucket is full.
1259 Whenever a packet is received, its size (converted to tokens) is
1260 compared to the number of tokens currently in the bucket. If the
1261 required number of tokens are available, they are removed and the
1262 packet is forwarded. Otherwise, the packet is dropped.
1265 Whenever it is not full, the bucket is refilled with tokens at the
1266 rate specified by <ref column="ingress_policing_rate"/>.
1270 Policing interacts badly with some network protocols, and especially
1271 with fragmented IP packets. Suppose that there is enough network
1272 activity to keep the bucket nearly empty all the time. Then this token
1273 bucket algorithm will forward a single packet every so often, with the
1274 period depending on packet size and on the configured rate. All of the
1275 fragments of an IP packets are normally transmitted back-to-back, as a
1276 group. In such a situation, therefore, only one of these fragments
1277 will be forwarded and the rest will be dropped. IP does not provide
1278 any way for the intended recipient to ask for only the remaining
1279 fragments. In such a case there are two likely possibilities for what
1280 will happen next: either all of the fragments will eventually be
1281 retransmitted (as TCP will do), in which case the same problem will
1282 recur, or the sender will not realize that its packet has been dropped
1283 and data will simply be lost (as some UDP-based protocols will do).
1284 Either way, it is possible that no forward progress will ever occur.
1286 <column name="ingress_policing_rate">
1288 Maximum rate for data received on this interface, in kbps. Data
1289 received faster than this rate is dropped. Set to <code>0</code>
1290 (the default) to disable policing.
1294 <column name="ingress_policing_burst">
1295 <p>Maximum burst size for data received on this interface, in kb. The
1296 default burst size if set to <code>0</code> is 1000 kb. This value
1297 has no effect if <ref column="ingress_policing_rate"/>
1298 is <code>0</code>.</p>
1300 Specifying a larger burst size lets the algorithm be more forgiving,
1301 which is important for protocols like TCP that react severely to
1302 dropped packets. The burst size should be at least the size of the
1303 interface's MTU. Specifying a value that is numerically at least as
1304 large as 10% of <ref column="ingress_policing_rate"/> helps TCP come
1305 closer to achieving the full rate.
1310 <group title="Connectivity Fault Management">
1312 802.1ag Connectivity Fault Management (CFM) allows a group of
1313 Maintenance Points (MPs) called a Maintenance Association (MA) to
1314 detect connectivity problems with each other. MPs within a MA should
1315 have complete and exclusive interconnectivity. This is verified by
1316 occasionally broadcasting Continuity Check Messages (CCMs) at a
1317 configurable transmission interval.
1320 <column name="cfm_mpid">
1321 A Maintenance Point ID (MPID) uniquely identifies each endpoint within
1322 a Maintenance Association. The MPID is used to identify this endpoint
1323 to other Maintenance Points in the MA. Each end of a link being
1324 monitored should have a different MPID. Must be configured to enable
1325 CFM on this <ref table="Interface"/>.
1328 <column name="cfm_remote_mpid">
1329 The MPID of the remote endpoint being monitored. If this
1330 <ref table="Interface"/> does not have connectivity to an endpoint
1331 advertising the configured MPID, a fault is signalled. Must be
1332 configured to enable CFM on this <ref table="Interface"/>
1335 <column name="cfm_fault">
1336 Indicates a connectivity fault triggered by an inability to receive
1337 heartbeats from the remote endpoint. When a fault is triggered on
1338 <ref table="Interface"/>s participating in bonds, they will be
1343 <group title="Other Features">
1345 <column name="lacp_current">
1346 Boolean value indicating LACP status for this interface. If true, this
1347 interface has current LACP information about its LACP partner. This
1348 information may be used to monitor the health of interfaces in a LACP
1349 enabled port. This column will be empty if LACP is not enabled.
1352 <column name="external_ids">
1353 Key-value pairs for use by external frameworks that integrate
1354 with Open vSwitch, rather than by Open vSwitch itself. System
1355 integrators should either use the Open vSwitch development
1356 mailing list to coordinate on common key-value definitions, or
1357 choose key names that are likely to be unique. The currently
1358 defined common key-value pairs are:
1360 <dt><code>attached-mac</code></dt>
1362 The MAC address programmed into the ``virtual hardware'' for this
1363 interface, in the form
1364 <var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>.
1365 For Citrix XenServer, this is the value of the <code>MAC</code>
1366 field in the VIF record for this interface.</dd>
1367 <dt><code>iface-id</code></dt>
1368 <dd>A system-unique identifier for the interface. On XenServer,
1369 this will commonly be the same as
1370 <ref column="external_ids" key="xs-vif-uuid"/>.</dd>
1373 Additionally the following key-value pairs specifically
1374 apply to an interface that represents a virtual Ethernet interface
1375 connected to a virtual machine. These key-value pairs should not be
1376 present for other types of interfaces. Keys whose names end
1377 in <code>-uuid</code> have values that uniquely identify the entity
1378 in question. For a Citrix XenServer hypervisor, these values are
1379 UUIDs in RFC 4122 format. Other hypervisors may use other
1382 <p>The currently defined key-value pairs for XenServer are:</p>
1384 <dt><code>xs-vif-uuid</code></dt>
1385 <dd>The virtual interface associated with this interface.</dd>
1386 <dt><code>xs-network-uuid</code></dt>
1387 <dd>The virtual network to which this interface is attached.</dd>
1388 <dt><code>xs-vm-uuid</code></dt>
1389 <dd>The VM to which this interface belongs.</dd>
1393 <column name="other_config">
1394 Key-value pairs for rarely used interface features.
1396 <dt><code>cfm_interval</code></dt>
1397 <dd> The transmission interval of CFM heartbeats in milliseconds.
1398 Three missed heartbeat receptions indicate a connectivity fault.
1399 Defaults to 1000ms. </dd>
1400 <dt><code>bond-stable-id</code></dt>
1401 <dd> A positive integer using in <code>stable</code> bond mode to
1402 make slave selection decisions. Allocating
1403 <ref column="other_config" key="bond-stable-id"/> values
1404 consistently across interfaces participating in a bond will
1405 guarantee consistent slave selection decisions across
1406 <code>ovs-vswitchd</code> instances when using <code>stable</code>
1408 <dt><code>lacp-port-id</code></dt>
1409 <dd> The LACP port ID of this <ref table="Interface"/>. Port IDs are
1410 used in LACP negotiations to identify individual ports
1411 participating in a bond. Must be a number between 1 and
1413 <dt><code>lacp-port-priority</code></dt>
1414 <dd> The LACP port priority of this <ref table="Interface"/>. In
1415 LACP negotiations <ref table="Interface"/>s with numerically lower
1416 priorities are preferred for aggregation. Must be a number between
1418 <dt><code>lacp-aggregation-key</code></dt>
1419 <dd> The LACP aggregation key of this <ref table="Interface"/>.
1420 <ref table="Interface"/>s with different aggregation keys may not
1421 be active within a given <ref table="Port"/> at the same time. Must
1422 be a number between 1 and 65535.</dd>
1426 <column name="statistics">
1428 Key-value pairs that report interface statistics. The current
1429 implementation updates these counters periodically. In the future,
1430 we plan to, instead, update them when an interface is created, when
1431 they are queried (e.g. using an OVSDB <code>select</code> operation),
1432 and just before an interface is deleted due to virtual interface
1433 hot-unplug or VM shutdown, and perhaps at other times, but not on any
1434 regular periodic basis.</p>
1436 The currently defined key-value pairs are listed below. These are
1437 the same statistics reported by OpenFlow in its <code>struct
1438 ofp_port_stats</code> structure. If an interface does not support a
1439 given statistic, then that pair is omitted.</p>
1442 Successful transmit and receive counters:
1444 <dt><code>rx_packets</code></dt>
1445 <dd>Number of received packets.</dd>
1446 <dt><code>rx_bytes</code></dt>
1447 <dd>Number of received bytes.</dd>
1448 <dt><code>tx_packets</code></dt>
1449 <dd>Number of transmitted packets.</dd>
1450 <dt><code>tx_bytes</code></dt>
1451 <dd>Number of transmitted bytes.</dd>
1457 <dt><code>rx_dropped</code></dt>
1458 <dd>Number of packets dropped by RX.</dd>
1459 <dt><code>rx_frame_err</code></dt>
1460 <dd>Number of frame alignment errors.</dd>
1461 <dt><code>rx_over_err</code></dt>
1462 <dd>Number of packets with RX overrun.</dd>
1463 <dt><code>rx_crc_err</code></dt>
1464 <dd>Number of CRC errors.</dd>
1465 <dt><code>rx_errors</code></dt>
1467 Total number of receive errors, greater than or equal
1468 to the sum of the above.
1475 <dt><code>tx_dropped</code></dt>
1476 <dd>Number of packets dropped by TX.</dd>
1477 <dt><code>collisions</code></dt>
1478 <dd>Number of collisions.</dd>
1479 <dt><code>tx_errors</code></dt>
1481 Total number of transmit errors, greater
1482 than or equal to the sum of the above.
1491 <table name="QoS" title="Quality of Service configuration">
1492 <p>Quality of Service (QoS) configuration for each Port that
1495 <column name="type">
1496 <p>The type of QoS to implement. The <ref table="Open_vSwitch"
1497 column="capabilities"/> column in the <ref table="Open_vSwitch"/> table
1498 identifies the types that a switch actually supports. The currently
1499 defined types are listed below:</p>
1501 <dt><code>linux-htb</code></dt>
1503 Linux ``hierarchy token bucket'' classifier. See tc-htb(8) (also at
1504 <code>http://linux.die.net/man/8/tc-htb</code>) and the HTB manual
1505 (<code>http://luxik.cdi.cz/~devik/qos/htb/manual/userg.htm</code>)
1506 for information on how this classifier works and how to configure it.
1510 <dt><code>linux-hfsc</code></dt>
1512 Linux "Hierarchical Fair Service Curve" classifier.
1513 See <code>http://linux-ip.net/articles/hfsc.en/</code> for
1514 information on how this classifier works.
1519 <column name="queues">
1520 <p>A map from queue numbers to <ref table="Queue"/> records. The
1521 supported range of queue numbers depend on <ref column="type"/>. The
1522 queue numbers are the same as the <code>queue_id</code> used in
1523 OpenFlow in <code>struct ofp_action_enqueue</code> and other
1524 structures. Queue 0 is used by OpenFlow output actions that do not
1525 specify a specific queue.</p>
1528 <column name="other_config">
1529 <p>Key-value pairs for configuring QoS features that depend on
1530 <ref column="type"/>.</p>
1531 <p>The <code>linux-htb</code> and <code>linux-hfsc</code> classes support
1532 the following key-value pairs:</p>
1534 <dt><code>max-rate</code></dt>
1535 <dd>Maximum rate shared by all queued traffic, in bit/s.
1536 Optional. If not specified, for physical interfaces, the
1537 default is the link rate. For other interfaces or if the
1538 link rate cannot be determined, the default is currently 100
1543 <column name="external_ids">
1544 Key-value pairs for use by external frameworks that integrate with Open
1545 vSwitch, rather than by Open vSwitch itself. System integrators should
1546 either use the Open vSwitch development mailing list to coordinate on
1547 common key-value definitions, or choose key names that are likely to be
1548 unique. No common key-value pairs are currently defined.
1552 <table name="Queue" title="QoS output queue.">
1553 <p>A configuration for a port output queue, used in configuring Quality of
1554 Service (QoS) features. May be referenced by <ref column="queues"
1555 table="QoS"/> column in <ref table="QoS"/> table.</p>
1557 <column name="other_config">
1558 <p>Key-value pairs for configuring the output queue. The supported
1559 key-value pairs and their meanings depend on the <ref column="type"/>
1560 of the <ref column="QoS"/> records that reference this row.</p>
1561 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1562 column="type"/> of <code>min-rate</code> are:</p>
1564 <dt><code>min-rate</code></dt>
1565 <dd>Minimum guaranteed bandwidth, in bit/s. Required. The
1566 floor value is 1500 bytes/s (12,000 bit/s).</dd>
1568 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1569 column="type"/> of <code>linux-htb</code> are:</p>
1571 <dt><code>min-rate</code></dt>
1572 <dd>Minimum guaranteed bandwidth, in bit/s.</dd>
1573 <dt><code>max-rate</code></dt>
1574 <dd>Maximum allowed bandwidth, in bit/s. Optional. If specified, the
1575 queue's rate will not be allowed to exceed the specified value, even
1576 if excess bandwidth is available. If unspecified, defaults to no
1578 <dt><code>burst</code></dt>
1579 <dd>Burst size, in bits. This is the maximum amount of ``credits''
1580 that a queue can accumulate while it is idle. Optional. Details of
1581 the <code>linux-htb</code> implementation require a minimum burst
1582 size, so a too-small <code>burst</code> will be silently
1584 <dt><code>priority</code></dt>
1585 <dd>A nonnegative 32-bit integer. Defaults to 0 if
1586 unspecified. A queue with a smaller <code>priority</code>
1587 will receive all the excess bandwidth that it can use before
1588 a queue with a larger value receives any. Specific priority
1589 values are unimportant; only relative ordering matters.</dd>
1591 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1592 column="type"/> of <code>linux-hfsc</code> are:</p>
1594 <dt><code>min-rate</code></dt>
1595 <dd>Minimum guaranteed bandwidth, in bit/s.</dd>
1596 <dt><code>max-rate</code></dt>
1597 <dd>Maximum allowed bandwidth, in bit/s. Optional. If specified, the
1598 queue's rate will not be allowed to exceed the specified value, even
1599 if excess bandwidth is available. If unspecified, defaults to no
1604 <column name="external_ids">
1605 Key-value pairs for use by external frameworks that integrate with Open
1606 vSwitch, rather than by Open vSwitch itself. System integrators should
1607 either use the Open vSwitch development mailing list to coordinate on
1608 common key-value definitions, or choose key names that are likely to be
1609 unique. No common key-value pairs are currently defined.
1613 <table name="Mirror" title="Port mirroring (SPAN/RSPAN).">
1614 <p>A port mirror within a <ref table="Bridge"/>.</p>
1615 <p>A port mirror configures a bridge to send selected frames to special
1616 ``mirrored'' ports, in addition to their normal destinations. Mirroring
1617 traffic may also be referred to as SPAN or RSPAN, depending on the
1618 mechanism used for delivery.</p>
1620 <column name="name">
1621 Arbitrary identifier for the <ref table="Mirror"/>.
1624 <group title="Selecting Packets for Mirroring">
1626 To be selected for mirroring, a given packet must enter or leave the
1627 bridge through a selected port and it must also be in one of the
1631 <column name="select_all">
1632 If true, every packet arriving or departing on any port is
1633 selected for mirroring.
1636 <column name="select_dst_port">
1637 Ports on which departing packets are selected for mirroring.
1640 <column name="select_src_port">
1641 Ports on which arriving packets are selected for mirroring.
1644 <column name="select_vlan">
1645 VLANs on which packets are selected for mirroring. An empty set
1646 selects packets on all VLANs.
1650 <group title="Mirroring Destination Configuration">
1652 These columns are mutually exclusive. Exactly one of them must be
1656 <column name="output_port">
1657 <p>Output port for selected packets, if nonempty.</p>
1658 <p>Specifying a port for mirror output reserves that port exclusively
1659 for mirroring. No frames other than those selected for mirroring
1660 will be forwarded to the port, and any frames received on the port
1661 will be discarded.</p>
1662 <p>This type of mirroring is sometimes called SPAN.</p>
1665 <column name="output_vlan">
1666 <p>Output VLAN for selected packets, if nonempty.</p>
1667 <p>The frames will be sent out all ports that trunk
1668 <ref column="output_vlan"/>, as well as any ports with implicit VLAN
1669 <ref column="output_vlan"/>. When a mirrored frame is sent out a
1670 trunk port, the frame's VLAN tag will be set to
1671 <ref column="output_vlan"/>, replacing any existing tag; when it is
1672 sent out an implicit VLAN port, the frame will not be tagged. This
1673 type of mirroring is sometimes called RSPAN.</p>
1675 The following destination MAC addresses will not be mirrored to a
1676 VLAN to avoid confusing switches that interpret the protocols that
1680 <dt><code>01:80:c2:00:00:00</code></dt>
1681 <dd>IEEE 802.1D Spanning Tree Protocol (STP).</dd>
1683 <dt><code>01:80:c2:00:00:01</code></dt>
1684 <dd>IEEE Pause frame.</dd>
1686 <dt><code>01:80:c2:00:00:0<var>x</var></code></dt>
1687 <dd>Other reserved protocols.</dd>
1689 <dt><code>01:00:0c:cc:cc:cc</code></dt>
1691 Cisco Discovery Protocol (CDP), VLAN Trunking Protocol (VTP),
1692 Dynamic Trunking Protocol (DTP), Port Aggregation Protocol (PAgP),
1696 <dt><code>01:00:0c:cc:cc:cd</code></dt>
1697 <dd>Cisco Shared Spanning Tree Protocol PVSTP+.</dd>
1699 <dt><code>01:00:0c:cd:cd:cd</code></dt>
1700 <dd>Cisco STP Uplink Fast.</dd>
1702 <dt><code>01:00:0c:00:00:00</code></dt>
1703 <dd>Cisco Inter Switch Link.</dd>
1705 <p><em>Please note:</em> Mirroring to a VLAN can disrupt a network that
1706 contains unmanaged switches. Consider an unmanaged physical switch
1707 with two ports: port 1, connected to an end host, and port 2,
1708 connected to an Open vSwitch configured to mirror received packets
1709 into VLAN 123 on port 2. Suppose that the end host sends a packet on
1710 port 1 that the physical switch forwards to port 2. The Open vSwitch
1711 forwards this packet to its destination and then reflects it back on
1712 port 2 in VLAN 123. This reflected packet causes the unmanaged
1713 physical switch to replace the MAC learning table entry, which
1714 correctly pointed to port 1, with one that incorrectly points to port
1715 2. Afterward, the physical switch will direct packets destined for
1716 the end host to the Open vSwitch on port 2, instead of to the end
1717 host on port 1, disrupting connectivity. If mirroring to a VLAN is
1718 desired in this scenario, then the physical switch must be replaced
1719 by one that learns Ethernet addresses on a per-VLAN basis. In
1720 addition, learning should be disabled on the VLAN containing mirrored
1721 traffic. If this is not done then intermediate switches will learn
1722 the MAC address of each end host from the mirrored traffic. If
1723 packets being sent to that end host are also mirrored, then they will
1724 be dropped since the switch will attempt to send them out the input
1725 port. Disabling learning for the VLAN will cause the switch to
1726 correctly send the packet out all ports configured for that VLAN. If
1727 Open vSwitch is being used as an intermediate switch, learning can be
1728 disabled by adding the mirrored VLAN to <ref column="flood_vlans"/>
1729 in the appropriate <ref table="Bridge"/> table or tables.</p>
1733 <group title="Other Features">
1734 <column name="external_ids">
1735 Key-value pairs for use by external frameworks that integrate with Open
1736 vSwitch, rather than by Open vSwitch itself. System integrators should
1737 either use the Open vSwitch development mailing list to coordinate on
1738 common key-value definitions, or choose key names that are likely to be
1739 unique. No common key-value pairs are currently defined.
1744 <table name="Controller" title="OpenFlow controller configuration.">
1745 <p>An OpenFlow controller.</p>
1748 Open vSwitch supports two kinds of OpenFlow controllers:
1752 <dt>Primary controllers</dt>
1755 This is the kind of controller envisioned by the OpenFlow 1.0
1756 specification. Usually, a primary controller implements a network
1757 policy by taking charge of the switch's flow table.
1761 Open vSwitch initiates and maintains persistent connections to
1762 primary controllers, retrying the connection each time it fails or
1763 drops. The <ref table="Bridge" column="fail_mode"/> column in the
1764 <ref table="Bridge"/> table applies to primary controllers.
1768 Open vSwitch permits a bridge to have any number of primary
1769 controllers. When multiple controllers are configured, Open
1770 vSwitch connects to all of them simultaneously. Because
1771 OpenFlow 1.0 does not specify how multiple controllers
1772 coordinate in interacting with a single switch, more than
1773 one primary controller should be specified only if the
1774 controllers are themselves designed to coordinate with each
1775 other. (The Nicira-defined <code>NXT_ROLE</code> OpenFlow
1776 vendor extension may be useful for this.)
1779 <dt>Service controllers</dt>
1782 These kinds of OpenFlow controller connections are intended for
1783 occasional support and maintenance use, e.g. with
1784 <code>ovs-ofctl</code>. Usually a service controller connects only
1785 briefly to inspect or modify some of a switch's state.
1789 Open vSwitch listens for incoming connections from service
1790 controllers. The service controllers initiate and, if necessary,
1791 maintain the connections from their end. The <ref table="Bridge"
1792 column="fail_mode"/> column in the <ref table="Bridge"/> table does
1793 not apply to service controllers.
1797 Open vSwitch supports configuring any number of service controllers.
1803 The <ref column="target"/> determines the type of controller.
1806 <group title="Core Features">
1807 <column name="target">
1808 <p>Connection method for controller.</p>
1810 The following connection methods are currently supported for primary
1814 <dt><code>ssl:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1816 <p>The specified SSL <var>port</var> (default: 6633) on the host at
1817 the given <var>ip</var>, which must be expressed as an IP address
1818 (not a DNS name). The <ref table="Open_vSwitch" column="ssl"/>
1819 column in the <ref table="Open_vSwitch"/> table must point to a
1820 valid SSL configuration when this form is used.</p>
1821 <p>SSL support is an optional feature that is not always built as
1822 part of Open vSwitch.</p>
1824 <dt><code>tcp:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1825 <dd>The specified TCP <var>port</var> (default: 6633) on the host at
1826 the given <var>ip</var>, which must be expressed as an IP address
1827 (not a DNS name).</dd>
1830 The following connection methods are currently supported for service
1834 <dt><code>pssl:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1837 Listens for SSL connections on the specified TCP <var>port</var>
1838 (default: 6633). If <var>ip</var>, which must be expressed as an
1839 IP address (not a DNS name), is specified, then connections are
1840 restricted to the specified local IP address.
1843 The <ref table="Open_vSwitch" column="ssl"/> column in the <ref
1844 table="Open_vSwitch"/> table must point to a valid SSL
1845 configuration when this form is used.
1847 <p>SSL support is an optional feature that is not always built as
1848 part of Open vSwitch.</p>
1850 <dt><code>ptcp:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1852 Listens for connections on the specified TCP <var>port</var>
1853 (default: 6633). If <var>ip</var>, which must be expressed as an
1854 IP address (not a DNS name), is specified, then connections are
1855 restricted to the specified local IP address.
1858 <p>When multiple controllers are configured for a single bridge, the
1859 <ref column="target"/> values must be unique. Duplicate
1860 <ref column="target"/> values yield unspecified results.</p>
1863 <column name="connection_mode">
1864 <p>If it is specified, this setting must be one of the following
1865 strings that describes how Open vSwitch contacts this OpenFlow
1866 controller over the network:</p>
1869 <dt><code>in-band</code></dt>
1870 <dd>In this mode, this controller's OpenFlow traffic travels over the
1871 bridge associated with the controller. With this setting, Open
1872 vSwitch allows traffic to and from the controller regardless of the
1873 contents of the OpenFlow flow table. (Otherwise, Open vSwitch
1874 would never be able to connect to the controller, because it did
1875 not have a flow to enable it.) This is the most common connection
1876 mode because it is not necessary to maintain two independent
1878 <dt><code>out-of-band</code></dt>
1879 <dd>In this mode, OpenFlow traffic uses a control network separate
1880 from the bridge associated with this controller, that is, the
1881 bridge does not use any of its own network devices to communicate
1882 with the controller. The control network must be configured
1883 separately, before or after <code>ovs-vswitchd</code> is started.
1887 <p>If not specified, the default is implementation-specific.</p>
1891 <group title="Controller Failure Detection and Handling">
1892 <column name="max_backoff">
1893 Maximum number of milliseconds to wait between connection attempts.
1894 Default is implementation-specific.
1897 <column name="inactivity_probe">
1898 Maximum number of milliseconds of idle time on connection to
1899 controller before sending an inactivity probe message. If Open
1900 vSwitch does not communicate with the controller for the specified
1901 number of seconds, it will send a probe. If a response is not
1902 received for the same additional amount of time, Open vSwitch
1903 assumes the connection has been broken and attempts to reconnect.
1904 Default is implementation-specific. A value of 0 disables
1909 <group title="OpenFlow Rate Limiting">
1910 <column name="controller_rate_limit">
1911 <p>The maximum rate at which packets in unknown flows will be
1912 forwarded to the OpenFlow controller, in packets per second. This
1913 feature prevents a single bridge from overwhelming the controller.
1914 If not specified, the default is implementation-specific.</p>
1915 <p>In addition, when a high rate triggers rate-limiting, Open
1916 vSwitch queues controller packets for each port and transmits
1917 them to the controller at the configured rate. The number of
1918 queued packets is limited by
1919 the <ref column="controller_burst_limit"/> value. The packet
1920 queue is shared fairly among the ports on a bridge.</p><p>Open
1921 vSwitch maintains two such packet rate-limiters per bridge.
1922 One of these applies to packets sent up to the controller
1923 because they do not correspond to any flow. The other applies
1924 to packets sent up to the controller by request through flow
1925 actions. When both rate-limiters are filled with packets, the
1926 actual rate that packets are sent to the controller is up to
1927 twice the specified rate.</p>
1930 <column name="controller_burst_limit">
1931 In conjunction with <ref column="controller_rate_limit"/>,
1932 the maximum number of unused packet credits that the bridge will
1933 allow to accumulate, in packets. If not specified, the default
1934 is implementation-specific.
1938 <group title="Additional In-Band Configuration">
1939 <p>These values are considered only in in-band control mode (see
1940 <ref column="connection_mode"/>).</p>
1942 <p>When multiple controllers are configured on a single bridge, there
1943 should be only one set of unique values in these columns. If different
1944 values are set for these columns in different controllers, the effect
1947 <column name="local_ip">
1948 The IP address to configure on the local port,
1949 e.g. <code>192.168.0.123</code>. If this value is unset, then
1950 <ref column="local_netmask"/> and <ref column="local_gateway"/> are
1954 <column name="local_netmask">
1955 The IP netmask to configure on the local port,
1956 e.g. <code>255.255.255.0</code>. If <ref column="local_ip"/> is set
1957 but this value is unset, then the default is chosen based on whether
1958 the IP address is class A, B, or C.
1961 <column name="local_gateway">
1962 The IP address of the gateway to configure on the local port, as a
1963 string, e.g. <code>192.168.0.1</code>. Leave this column unset if
1964 this network has no gateway.
1968 <group title="Other Features">
1969 <column name="external_ids">
1970 Key-value pairs for use by external frameworks that integrate with Open
1971 vSwitch, rather than by Open vSwitch itself. System integrators should
1972 either use the Open vSwitch development mailing list to coordinate on
1973 common key-value definitions, or choose key names that are likely to be
1974 unique. No common key-value pairs are currently defined.
1978 <group title="Controller Status">
1979 <column name="is_connected">
1980 <code>true</code> if currently connected to this controller,
1981 <code>false</code> otherwise.
1984 <column name="role">
1985 <p>The level of authority this controller has on the associated
1986 bridge. Possible values are:</p>
1988 <dt><code>other</code></dt>
1989 <dd>Allows the controller access to all OpenFlow features.</dd>
1990 <dt><code>master</code></dt>
1991 <dd>Equivalent to <code>other</code>, except that there may be at
1992 most one master controller at a time. When a controller configures
1993 itself as <code>master</code>, any existing master is demoted to
1994 the <code>slave</code>role.</dd>
1995 <dt><code>slave</code></dt>
1996 <dd>Allows the controller read-only access to OpenFlow features.
1997 Attempts to modify the flow table will be rejected with an
1998 error. Slave controllers do not receive OFPT_PACKET_IN or
1999 OFPT_FLOW_REMOVED messages, but they do receive OFPT_PORT_STATUS
2004 <column name="status">
2005 <p>Key-value pairs that report controller status.</p>
2007 <dt><code>last_error</code></dt>
2008 <dd>A human-readable description of the last error on the connection
2009 to the controller; i.e. <code>strerror(errno)</code>. This key
2010 will exist only if an error has occurred.</dd>
2011 <dt><code>state</code></dt>
2012 <dd>The state of the connection to the controller. Possible values
2013 are: <code>VOID</code> (connection is disabled),
2014 <code>BACKOFF</code> (attempting to reconnect at an increasing
2015 period), <code>CONNECTING</code> (attempting to connect),
2016 <code>ACTIVE</code> (connected, remote host responsive), and
2017 <code>IDLE</code> (remote host idle, sending keep-alive). These
2018 values may change in the future. They are provided only for human
2020 <dt><code>sec_since_connect</code></dt>
2021 <dd>The amount of time since this controller last successfully
2022 connected to the switch (in seconds). Value is empty if controller
2023 has never successfully connected.</dd>
2024 <dt><code>sec_since_disconnect</code></dt>
2025 <dd>The amount of time since this controller last disconnected from
2026 the switch (in seconds). Value is empty if controller has never
2033 <table name="Manager" title="OVSDB management connection.">
2035 Configuration for a database connection to an Open vSwitch database
2040 This table primarily configures the Open vSwitch database
2041 (<code>ovsdb-server</code>), not the Open vSwitch switch
2042 (<code>ovs-vswitchd</code>). The switch does read the table to determine
2043 what connections should be treated as in-band.
2047 The Open vSwitch database server can initiate and maintain active
2048 connections to remote clients. It can also listen for database
2052 <group title="Core Features">
2053 <column name="target">
2054 <p>Connection method for managers.</p>
2056 The following connection methods are currently supported:
2059 <dt><code>ssl:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
2062 The specified SSL <var>port</var> (default: 6632) on the host at
2063 the given <var>ip</var>, which must be expressed as an IP address
2064 (not a DNS name). The <ref table="Open_vSwitch" column="ssl"/>
2065 column in the <ref table="Open_vSwitch"/> table must point to a
2066 valid SSL configuration when this form is used.
2069 SSL support is an optional feature that is not always built as
2070 part of Open vSwitch.
2074 <dt><code>tcp:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
2076 The specified TCP <var>port</var> (default: 6632) on the host at
2077 the given <var>ip</var>, which must be expressed as an IP address
2080 <dt><code>pssl:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
2083 Listens for SSL connections on the specified TCP <var>port</var>
2084 (default: 6632). If <var>ip</var>, which must be expressed as an
2085 IP address (not a DNS name), is specified, then connections are
2086 restricted to the specified local IP address.
2089 The <ref table="Open_vSwitch" column="ssl"/> column in the <ref
2090 table="Open_vSwitch"/> table must point to a valid SSL
2091 configuration when this form is used.
2094 SSL support is an optional feature that is not always built as
2095 part of Open vSwitch.
2098 <dt><code>ptcp:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
2100 Listens for connections on the specified TCP <var>port</var>
2101 (default: 6632). If <var>ip</var>, which must be expressed as an
2102 IP address (not a DNS name), is specified, then connections are
2103 restricted to the specified local IP address.
2106 <p>When multiple managers are configured, the <ref column="target"/>
2107 values must be unique. Duplicate <ref column="target"/> values yield
2108 unspecified results.</p>
2111 <column name="connection_mode">
2113 If it is specified, this setting must be one of the following strings
2114 that describes how Open vSwitch contacts this OVSDB client over the
2119 <dt><code>in-band</code></dt>
2121 In this mode, this connection's traffic travels over a bridge
2122 managed by Open vSwitch. With this setting, Open vSwitch allows
2123 traffic to and from the client regardless of the contents of the
2124 OpenFlow flow table. (Otherwise, Open vSwitch would never be able
2125 to connect to the client, because it did not have a flow to enable
2126 it.) This is the most common connection mode because it is not
2127 necessary to maintain two independent networks.
2129 <dt><code>out-of-band</code></dt>
2131 In this mode, the client's traffic uses a control network separate
2132 from that managed by Open vSwitch, that is, Open vSwitch does not
2133 use any of its own network devices to communicate with the client.
2134 The control network must be configured separately, before or after
2135 <code>ovs-vswitchd</code> is started.
2140 If not specified, the default is implementation-specific.
2145 <group title="Client Failure Detection and Handling">
2146 <column name="max_backoff">
2147 Maximum number of milliseconds to wait between connection attempts.
2148 Default is implementation-specific.
2151 <column name="inactivity_probe">
2152 Maximum number of milliseconds of idle time on connection to the client
2153 before sending an inactivity probe message. If Open vSwitch does not
2154 communicate with the client for the specified number of seconds, it
2155 will send a probe. If a response is not received for the same
2156 additional amount of time, Open vSwitch assumes the connection has been
2157 broken and attempts to reconnect. Default is implementation-specific.
2158 A value of 0 disables inactivity probes.
2162 <group title="Other Features">
2163 <column name="external_ids">
2164 Key-value pairs for use by external frameworks that integrate with Open
2165 vSwitch, rather than by Open vSwitch itself. System integrators should
2166 either use the Open vSwitch development mailing list to coordinate on
2167 common key-value definitions, or choose key names that are likely to be
2168 unique. No common key-value pairs are currently defined.
2172 <group title="Status">
2173 <column name="is_connected">
2174 <code>true</code> if currently connected to this manager,
2175 <code>false</code> otherwise.
2178 <column name="status">
2179 <p>Key-value pairs that report manager status.</p>
2181 <dt><code>last_error</code></dt>
2182 <dd>A human-readable description of the last error on the connection
2183 to the manager; i.e. <code>strerror(errno)</code>. This key
2184 will exist only if an error has occurred.</dd>
2187 <dt><code>state</code></dt>
2188 <dd>The state of the connection to the manager. Possible values
2189 are: <code>VOID</code> (connection is disabled),
2190 <code>BACKOFF</code> (attempting to reconnect at an increasing
2191 period), <code>CONNECTING</code> (attempting to connect),
2192 <code>ACTIVE</code> (connected, remote host responsive), and
2193 <code>IDLE</code> (remote host idle, sending keep-alive). These
2194 values may change in the future. They are provided only for human
2198 <dt><code>sec_since_connect</code></dt>
2199 <dd>The amount of time since this manager last successfully connected
2200 to the database (in seconds). Value is empty if manager has never
2201 successfully connected.</dd>
2204 <dt><code>sec_since_disconnect</code></dt>
2205 <dd>The amount of time since this manager last disconnected from the
2206 database (in seconds). Value is empty if manager has never
2210 <dt><code>locks_held</code></dt>
2211 <dt><code>locks_waiting</code></dt>
2212 <dt><code>locks_lost</code></dt>
2214 Space-separated lists of the names of OVSDB locks that the
2215 connection holds, is currently waiting to acquire, or has had
2216 stolen by another OVSDB client, respectively. Key-value pairs for
2217 lists that would be empty are omitted.
2221 <dt><code>n_connections</code></dt>
2224 When <ref column="target"/> specifies a connection method that
2225 listens for inbound connections (e.g. <code>ptcp:</code> or
2226 <code>pssl:</code>) and more than one connection is actually
2227 active, the value is the number of active connections.
2228 Otherwise, this key-value pair is omitted.
2231 When multiple connections are active, status columns and
2232 key-value pairs (other than this one) report the status of one
2233 arbitrarily chosen connection.
2241 <table name="NetFlow">
2242 A NetFlow target. NetFlow is a protocol that exports a number of
2243 details about terminating IP flows, such as the principals involved
2246 <column name="targets">
2247 NetFlow targets in the form
2248 <code><var>ip</var>:<var>port</var></code>. The <var>ip</var>
2249 must be specified numerically, not as a DNS name.
2252 <column name="engine_id">
2253 Engine ID to use in NetFlow messages. Defaults to datapath index
2257 <column name="engine_type">
2258 Engine type to use in NetFlow messages. Defaults to datapath
2259 index if not specified.
2262 <column name="active_timeout">
2263 The interval at which NetFlow records are sent for flows that are
2264 still active, in seconds. A value of <code>0</code> requests the
2265 default timeout (currently 600 seconds); a value of <code>-1</code>
2266 disables active timeouts.
2269 <column name="add_id_to_interface">
2270 <p>If this column's value is <code>false</code>, the ingress and egress
2271 interface fields of NetFlow flow records are derived from OpenFlow port
2272 numbers. When it is <code>true</code>, the 7 most significant bits of
2273 these fields will be replaced by the least significant 7 bits of the
2274 engine id. This is useful because many NetFlow collectors do not
2275 expect multiple switches to be sending messages from the same host, so
2276 they do not store the engine information which could be used to
2277 disambiguate the traffic.</p>
2278 <p>When this option is enabled, a maximum of 508 ports are supported.</p>
2281 <column name="external_ids">
2282 Key-value pairs for use by external frameworks that integrate with Open
2283 vSwitch, rather than by Open vSwitch itself. System integrators should
2284 either use the Open vSwitch development mailing list to coordinate on
2285 common key-value definitions, or choose key names that are likely to be
2286 unique. No common key-value pairs are currently defined.
2291 SSL configuration for an Open_vSwitch.
2293 <column name="private_key">
2294 Name of a PEM file containing the private key used as the switch's
2295 identity for SSL connections to the controller.
2298 <column name="certificate">
2299 Name of a PEM file containing a certificate, signed by the
2300 certificate authority (CA) used by the controller and manager,
2301 that certifies the switch's private key, identifying a trustworthy
2305 <column name="ca_cert">
2306 Name of a PEM file containing the CA certificate used to verify
2307 that the switch is connected to a trustworthy controller.
2310 <column name="bootstrap_ca_cert">
2311 If set to <code>true</code>, then Open vSwitch will attempt to
2312 obtain the CA certificate from the controller on its first SSL
2313 connection and save it to the named PEM file. If it is successful,
2314 it will immediately drop the connection and reconnect, and from then
2315 on all SSL connections must be authenticated by a certificate signed
2316 by the CA certificate thus obtained. <em>This option exposes the
2317 SSL connection to a man-in-the-middle attack obtaining the initial
2318 CA certificate.</em> It may still be useful for bootstrapping.
2321 <column name="external_ids">
2322 Key-value pairs for use by external frameworks that integrate with Open
2323 vSwitch, rather than by Open vSwitch itself. System integrators should
2324 either use the Open vSwitch development mailing list to coordinate on
2325 common key-value definitions, or choose key names that are likely to be
2326 unique. No common key-value pairs are currently defined.
2330 <table name="sFlow">
2331 <p>An sFlow(R) target. sFlow is a protocol for remote monitoring
2334 <column name="agent">
2335 Name of the network device whose IP address should be reported as the
2336 ``agent address'' to collectors. If not specified, the IP address
2337 defaults to the <ref table="Controller" column="local_ip"/> in the
2338 collector's <ref table="Controller"/>. If an agent IP address cannot be
2339 determined either way, sFlow is disabled.
2342 <column name="header">
2343 Number of bytes of a sampled packet to send to the collector.
2344 If not specified, the default is 128 bytes.
2347 <column name="polling">
2348 Polling rate in seconds to send port statistics to the collector.
2349 If not specified, defaults to 30 seconds.
2352 <column name="sampling">
2353 Rate at which packets should be sampled and sent to the collector.
2354 If not specified, defaults to 400, which means one out of 400
2355 packets, on average, will be sent to the collector.
2358 <column name="targets">
2359 sFlow targets in the form
2360 <code><var>ip</var>:<var>port</var></code>.
2363 <column name="external_ids">
2364 Key-value pairs for use by external frameworks that integrate with Open
2365 vSwitch, rather than by Open vSwitch itself. System integrators should
2366 either use the Open vSwitch development mailing list to coordinate on
2367 common key-value definitions, or choose key names that are likely to be
2368 unique. No common key-value pairs are currently defined.
2372 <table name="Capability">
2373 <p>Records in this table describe functionality supported by the hardware
2374 and software platform on which this Open vSwitch is based. Clients
2375 should not modify this table.</p>
2377 <p>A record in this table is meaningful only if it is referenced by the
2378 <ref table="Open_vSwitch" column="capabilities"/> column in the
2379 <ref table="Open_vSwitch"/> table. The key used to reference it, called
2380 the record's ``category,'' determines the meanings of the
2381 <ref column="details"/> column. The following general forms of
2382 categories are currently defined:</p>
2385 <dt><code>qos-<var>type</var></code></dt>
2386 <dd><var>type</var> is supported as the value for
2387 <ref column="type" table="QoS"/> in the <ref table="QoS"/> table.
2391 <column name="details">
2392 <p>Key-value pairs that describe capabilities. The meaning of the pairs
2393 depends on the category key that the <ref table="Open_vSwitch"
2394 column="capabilities"/> column in the <ref table="Open_vSwitch"/> table
2395 uses to reference this record, as described above.</p>
2397 <p>The presence of a record for category <code>qos-<var>type</var></code>
2398 indicates that the switch supports <var>type</var> as the value of
2399 the <ref table="QoS" column="type"/> column in the <ref table="QoS"/>
2400 table. The following key-value pairs are defined to further describe
2401 QoS capabilities:</p>
2404 <dt><code>n-queues</code></dt>
2405 <dd>Number of supported queues, as a positive integer. Keys in the
2406 <ref table="QoS" column="queues"/> column for <ref table="QoS"/>
2407 records whose <ref table="QoS" column="type"/> value
2408 equals <var>type</var> must range between 0 and this value minus one,