1 <?xml version="1.0" encoding="utf-8"?>
2 <database title="Open vSwitch Configuration Database">
3 <p>A database with this schema holds the configuration for one Open
4 vSwitch daemon. The root of the configuration for the daemon is
5 the <ref table="Open_vSwitch"/> table, which must have exactly one
6 record. Records in other tables are significant only when they
7 can be reached directly or indirectly from the
8 <ref table="Open_vSwitch"/> table.</p>
10 <table name="Open_vSwitch" title="Open vSwitch configuration.">
11 Configuration for an Open vSwitch daemon. There must be exactly one record
12 in the <ref table="Open_vSwitch"/> table.
14 <group title="Configuration">
15 <column name="bridges">
16 Set of bridges managed by the daemon.
20 SSL used globally by the daemon.
23 <column name="external_ids">
24 Key-value pairs for use by external frameworks that integrate
25 with Open vSwitch, rather than by Open vSwitch itself. System
26 integrators should either use the Open vSwitch development
27 mailing list to coordinate on common key-value definitions, or
28 choose key names that are likely to be unique. The currently
29 defined common key-value pairs are:
31 <dt><code>system-id</code></dt>
32 <dd>A unique identifier for the Open vSwitch's physical host.
33 The form of the identifier depends on the type of the host.
34 On a Citrix XenServer, this will likely be the same as
35 <code>xs-system-uuid</code>.</dd>
36 <dt><code>xs-system-uuid</code></dt>
37 <dd>The Citrix XenServer universally unique identifier for the
38 physical host as displayed by <code>xe host-list</code>.</dd>
43 <group title="Status">
44 <column name="next_cfg">
45 Sequence number for client to increment. When a client modifies
46 any part of the database configuration and wishes to wait for
47 Open vSwitch to finish applying the changes, it may increment
51 <column name="cur_cfg">
52 Sequence number that Open vSwitch sets to the current value of
53 <ref column="next_cfg"/> after it finishes applying a set of
54 configuration changes.
57 <column name="capabilities">
58 Describes functionality supported by the hardware and software platform
59 on which this Open vSwitch is based. Clients should not modify this
60 column. See the <ref table="Capability"/> description for defined
61 capability categories and the meaning of associated
62 <ref table="Capability"/> records.
65 <column name="statistics">
67 Key-value pairs that report statistics about a system running an Open
68 vSwitch. These are updated periodically (currently, every 5
69 seconds). Key-value pairs that cannot be determined or that do not
70 apply to a platform are omitted.
74 <dt><code>cpu</code></dt>
77 Number of CPU processors, threads, or cores currently online and
78 available to the operating system on which Open vSwitch is
79 running, as an integer. This may be less than the number
80 installed, if some are not online or if they are not available to
84 Open vSwitch userspace processes are not multithreaded, but the
85 Linux kernel-based datapath is.
89 <dt><code>load_average</code></dt>
92 A comma-separated list of three floating-point numbers,
93 representing the system load average over the last 1, 5, and 15
94 minutes, respectively.
98 <dt><code>memory</code></dt>
101 A comma-separated list of integers, each of which represents a
102 quantity of memory in kilobytes that describes the operating
103 system on which Open vSwitch is running. In respective order,
108 <li>Total amount of RAM allocated to the OS.</li>
109 <li>RAM allocated to the OS that is in use.</li>
110 <li>RAM that can be flushed out to disk or otherwise discarded
111 if that space is needed for another purpose. This number is
112 necessarily less than or equal to the previous value.</li>
113 <li>Total disk space allocated for swap.</li>
114 <li>Swap space currently in use.</li>
118 On Linux, all five values can be determined and are included. On
119 other operating systems, only the first two values can be
120 determined, so the list will only have two values.
124 <dt><code>process_</code><var>name</var></dt>
127 One such key-value pair will exist for each running Open vSwitch
128 daemon process, with <var>name</var> replaced by the daemon's
129 name (e.g. <code>process_ovs-vswitchd</code>). The value is a
130 comma-separated list of integers. The integers represent the
131 following, with memory measured in kilobytes and durations in
136 <li>The process's virtual memory size.</li>
137 <li>The process's resident set size.</li>
138 <li>The amount of user and system CPU time consumed by the
140 <li>The number of times that the process has crashed and been
141 automatically restarted by the monitor.</li>
142 <li>The duration since the process was started.</li>
143 <li>The duration for which the process has been running.</li>
147 The interpretation of some of these values depends on whether the
148 process was started with the <option>--monitor</option>. If it
149 was not, then the crash count will always be 0 and the two
150 durations will always be the same. If <option>--monitor</option>
151 was given, then the crash count may be positive; if it is, the
152 latter duration is the amount of time since the most recent crash
157 There will be one key-value pair for each file in Open vSwitch's
158 ``run directory'' (usually <code>/var/run/openvswitch</code>)
159 whose name ends in <code>.pid</code>, whose contents are a
160 process ID, and which is locked by a running process. The
161 <var>name</var> is taken from the pidfile's name.
165 Currently Open vSwitch is only able to obtain all of the above
166 detail on Linux systems. On other systems, the same key-value
167 pairs will be present but the values will always be the empty
172 <dt><code>file_systems</code></dt>
175 A space-separated list of information on local, writable file
176 systems. Each item in the list describes one file system and
177 consists in turn of a comma-separated list of the following:
181 <li>Mount point, e.g. <code>/</code> or <code>/var/log</code>.
182 Any spaces or commas in the mount point are replaced by
184 <li>Total size, in kilobytes, as an integer.</li>
185 <li>Amount of storage in use, in kilobytes, as an integer.</li>
189 This key-value pair is omitted if there are no local, writable
190 file systems or if Open vSwitch cannot obtain the needed
198 <group title="Version Reporting">
200 These columns report the types and versions of the hardware and
201 software running Open vSwitch. We recommend in general that software
202 should test whether specific features are supported instead of relying
203 on version number checks. These values are primarily intended for
204 reporting to human administrators.
207 <column name="ovs_version">
208 The Open vSwitch version number, e.g. <code>1.1.0pre2</code>.
209 If Open vSwitch was configured with a build number, then it is
210 also included, e.g. <code>1.1.0pre2+build4948</code>.
213 <column name="db_version">
215 The database schema version number in the form
216 <code><var>major</var>.<var>minor</var>.<var>tweak</var></code>,
217 e.g. <code>1.2.3</code>. Whenever the database schema is changed in
218 a non-backward compatible way (e.g. deleting a column or a table),
219 <var>major</var> is incremented. When the database schema is changed
220 in a backward compatible way (e.g. adding a new column),
221 <var>minor</var> is incremented. When the database schema is changed
222 cosmetically (e.g. reindenting its syntax), <var>tweak</var> is
227 The schema version is part of the database schema, so it can also be
228 retrieved by fetching the schema using the Open vSwitch database
233 <column name="system_type">
235 An identifier for the type of system on top of which Open vSwitch
236 runs, e.g. <code>XenServer</code> or <code>KVM</code>.
239 System integrators are responsible for choosing and setting an
240 appropriate value for this column.
244 <column name="system_version">
246 The version of the system identified by <ref column="system_type"/>,
247 e.g. <code>5.5.0-24648p</code> on XenServer 5.5.0 build 24648.
250 System integrators are responsible for choosing and setting an
251 appropriate value for this column.
257 <group title="Database Configuration">
259 These columns primarily configure the Open vSwitch database
260 (<code>ovsdb-server</code>), not the Open vSwitch switch
261 (<code>ovs-vswitchd</code>). The OVSDB database also uses the <ref
262 column="ssl"/> settings.
266 The Open vSwitch switch does read the database configuration to
267 determine remote IP addresses to which in-band control should apply.
270 <column name="manager_options">
271 Database clients to which the Open vSwitch database server should
272 connect or to which it should listen, along with options for how these
273 connection should be configured. See the <ref table="Manager"/> table
274 for more information.
277 <column name="managers">
279 Remote database clients to which the Open vSwitch's database server
280 should connect or to which it should listen. Adding an OVSDB target
281 to this set is equivalent to adding it to <ref
282 column="manager_options"/> with all of the default options.
286 Use of this column is deprecated and may be removed sometime in the
287 future. New applications should use and set <ref
288 column="manager_options"/> instead.
294 <table name="Bridge">
296 Configuration for a bridge within an
297 <ref table="Open_vSwitch"/>.
300 A <ref table="Bridge"/> record represents an Ethernet switch with one or
301 more ``ports,'' which are the <ref table="Port"/> records pointed to by
302 the <ref table="Bridge"/>'s <ref column="ports"/> column.
305 <group title="Core Features">
307 Bridge identifier. Should be alphanumeric and no more than about 8
308 bytes long. Must be unique among the names of ports, interfaces, and
312 <column name="ports">
313 Ports included in the bridge.
316 <column name="mirrors">
317 Port mirroring configuration.
320 <column name="netflow">
321 NetFlow configuration.
324 <column name="sflow">
328 <column name="flood_vlans">
329 VLAN IDs of VLANs on which MAC address learning should be disabled, so
330 that packets are flooded instead of being sent to specific ports that
331 are believed to contain packets' destination MACs. This should
332 ordinarily be used to disable MAC learning on VLANs used for mirroring
333 (RSPAN VLANs). It may also be useful for debugging.
337 <group title="OpenFlow Configuration">
338 <column name="controller">
339 OpenFlow controller set. If unset, then no OpenFlow controllers
343 <column name="fail_mode">
344 <p>When a controller is configured, it is, ordinarily, responsible
345 for setting up all flows on the switch. Thus, if the connection to
346 the controller fails, no new network connections can be set up.
347 If the connection to the controller stays down long enough,
348 no packets can pass through the switch at all. This setting
349 determines the switch's response to such a situation. It may be set
350 to one of the following:
352 <dt><code>standalone</code></dt>
353 <dd>If no message is received from the controller for three
354 times the inactivity probe interval
355 (see <ref column="inactivity_probe"/>), then Open vSwitch
356 will take over responsibility for setting up flows. In
357 this mode, Open vSwitch causes the bridge to act like an
358 ordinary MAC-learning switch. Open vSwitch will continue
359 to retry connecting to the controller in the background
360 and, when the connection succeeds, it will discontinue its
361 standalone behavior.</dd>
362 <dt><code>secure</code></dt>
363 <dd>Open vSwitch will not set up flows on its own when the
364 controller connection fails or when no controllers are
365 defined. The bridge will continue to retry connecting to
366 any defined controllers forever.</dd>
369 <p>If this value is unset, the default is implementation-specific.</p>
370 <p>When more than one controller is configured,
371 <ref column="fail_mode"/> is considered only when none of the
372 configured controllers can be contacted.</p>
375 <column name="datapath_id">
376 Reports the OpenFlow datapath ID in use. Exactly 16 hex
377 digits. (Setting this column will have no useful effect. Set
378 <ref column="other_config"/>:<code>other-config</code>
383 <group title="Other Features">
384 <column name="datapath_type">
385 Name of datapath provider. The kernel datapath has
386 type <code>system</code>. The userspace datapath has
387 type <code>netdev</code>.
390 <column name="external_ids">
391 Key-value pairs for use by external frameworks that integrate
392 with Open vSwitch, rather than by Open vSwitch itself. System
393 integrators should either use the Open vSwitch development
394 mailing list to coordinate on common key-value definitions, or
395 choose key names that are likely to be unique. The currently
396 defined key-value pairs are:
398 <dt><code>bridge-id</code></dt>
399 <dd>A unique identifier of the bridge. On Citrix XenServer this
400 will commonly be the same as <code>xs-network-uuids</code>.</dd>
401 <dt><code>xs-network-uuids</code></dt>
402 <dd>Semicolon-delimited set of universally unique identifier(s) for
403 the network with which this bridge is associated on a Citrix
404 XenServer host. The network identifiers are RFC 4122 UUIDs as
405 displayed by, e.g., <code>xe network-list</code>.</dd>
409 <column name="other_config">
410 Key-value pairs for configuring rarely used bridge
411 features. The currently defined key-value pairs are:
413 <dt><code>datapath-id</code></dt>
415 digits to set the OpenFlow datapath ID to a specific
416 value. May not be all-zero.</dd>
417 <dt><code>disable-in-band</code></dt>
418 <dd>If set to <code>true</code>, disable in-band control on
419 the bridge regardless of controller and manager settings.</dd>
420 <dt><code>hwaddr</code></dt>
421 <dd>An Ethernet address in the form
422 <var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>
423 to set the hardware address of the local port and influence the
425 <dt><code>in-band-queue</code></dt>
427 A queue ID as a nonnegative integer. This sets the OpenFlow queue
428 ID that will be used by flows set up by in-band control on this
429 bridge. If unset, or if the port used by an in-band control flow
430 does not have QoS configured, or if the port does not have a queue
431 with the specified ID, the default queue is used instead.
438 <table name="Port" table="Port or bond configuration.">
439 <p>A port within a <ref table="Bridge"/>.</p>
440 <p>Most commonly, a port has exactly one ``interface,'' pointed to by its
441 <ref column="interfaces"/> column. Such a port logically
442 corresponds to a port on a physical Ethernet switch. A port
443 with more than one interface is a ``bonded port'' (see
444 <ref group="Bonding Configuration"/>).</p>
445 <p>Some properties that one might think as belonging to a port are actually
446 part of the port's <ref table="Interface"/> members.</p>
449 Port name. Should be alphanumeric and no more than about 8
450 bytes long. May be the same as the interface name, for
451 non-bonded ports. Must otherwise be unique among the names of
452 ports, interfaces, and bridges on a host.
455 <column name="interfaces">
456 The port's interfaces. If there is more than one, this is a
460 <group title="VLAN Configuration">
461 <p>A bridge port must be configured for VLANs in one of two
462 mutually exclusive ways:
464 <li>A ``trunk port'' has an empty value for <ref
465 column="tag"/>. Its <ref column="trunks"/> value may be
466 empty or non-empty.</li>
467 <li>An ``implicitly tagged VLAN port'' or ``access port''
468 has an nonempty value for <ref column="tag"/>. Its
469 <ref column="trunks"/> value must be empty.</li>
471 If <ref column="trunks"/> and <ref column="tag"/> are both
472 nonempty, the configuration is ill-formed.
477 If this is an access port (see above), the port's implicitly
478 tagged VLAN. Must be empty if this is a trunk port.
481 Frames arriving on trunk ports will be forwarded to this
482 port only if they are tagged with the given VLAN (or, if
483 <ref column="tag"/> is 0, then if they lack a VLAN header).
484 Frames arriving on other access ports will be forwarded to
485 this port only if they have the same <ref column="tag"/>
486 value. Frames forwarded to this port will not have an
490 When a frame with a 802.1Q header that indicates a nonzero
491 VLAN is received on an access port, it is discarded.
495 <column name="trunks">
497 If this is a trunk port (see above), the 802.1Q VLAN(s) that
498 this port trunks; if it is empty, then the port trunks all
499 VLANs. Must be empty if this is an access port.
502 Frames arriving on trunk ports are dropped if they are not
503 in one of the specified VLANs. For this purpose, packets
504 that have no VLAN header are treated as part of VLAN 0.
509 <group title="Bonding Configuration">
510 <p>A port that has more than one interface is a ``bonded port.''
511 Bonding allows for load balancing and fail-over. Open vSwitch
512 supports ``source load balancing'' (SLB) bonding, which
513 assigns flows to slaves based on source MAC address and output VLAN,
514 with periodic rebalancing as traffic patterns change. This form of
515 bonding does not require 802.3ad or other special support from the
516 upstream switch to which the slave devices are connected.</p>
518 <p>These columns apply only to bonded ports. Their values are
519 otherwise ignored.</p>
521 <column name="bond_updelay">
522 <p>For a bonded port, the number of milliseconds for which carrier must
523 stay up on an interface before the interface is considered to be up.
524 Specify <code>0</code> to enable the interface immediately.</p>
525 <p>This setting is honored only when at least one bonded interface is
526 already enabled. When no interfaces are enabled, then the first bond
527 interface to come up is enabled immediately.</p>
530 <column name="bond_downdelay">
531 For a bonded port, the number of milliseconds for which carrier must
532 stay down on an interface before the interface is considered to be
533 down. Specify <code>0</code> to disable the interface immediately.
536 <column name="bond_fake_iface">
537 For a bonded port, whether to create a fake internal interface with the
538 name of the port. Use only for compatibility with legacy software that
543 <group title="Other Features">
545 Quality of Service configuration for this port.
549 The MAC address to use for this port for the purpose of choosing the
550 bridge's MAC address. This column does not necessarily reflect the
551 port's actual MAC address, nor will setting it change the port's actual
555 <column name="fake_bridge">
556 Does this port represent a sub-bridge for its tagged VLAN within the
557 Bridge? See ovs-vsctl(8) for more information.
560 <column name="external_ids">
562 Key-value pairs for use by external frameworks that integrate with
563 Open vSwitch, rather than by Open vSwitch itself. System integrators
564 should either use the Open vSwitch development mailing list to
565 coordinate on common key-value definitions, or choose key names that
566 are likely to be unique.
569 No key-value pairs native to <ref table="Port"/> are currently
570 defined. For fake bridges (see the <ref column="fake_bridge"/>
571 column), external IDs for the fake bridge are defined here by
572 prefixing a <ref table="Bridge"/> <ref table="Bridge"
573 column="external_ids"/> key with <code>fake-bridge-</code>,
574 e.g. <code>fake-bridge-xs-network-uuids</code>.
578 <column name="other_config">
579 Key-value pairs for configuring rarely used port features. The
580 currently defined key-value pairs are:
582 <dt><code>hwaddr</code></dt>
583 <dd>An Ethernet address in the form
584 <code><var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var></code>.</dd>
585 <dt><code>bond-rebalance-interval</code></dt>
586 <dd>For a bonded port, the number of milliseconds between
587 successive attempts to rebalance the bond, that is, to
588 move source MACs and their flows from one interface on
589 the bond to another in an attempt to keep usage of each
590 interface roughly equal. The default is 10000 (10
591 seconds), and the minimum is 1000 (1 second).</dd>
597 <table name="Interface" title="One physical network device in a Port.">
598 An interface within a <ref table="Port"/>.
600 <group title="Core Features">
602 Interface name. Should be alphanumeric and no more than about 8 bytes
603 long. May be the same as the port name, for non-bonded ports. Must
604 otherwise be unique among the names of ports, interfaces, and bridges
609 <p>Ethernet address to set for this interface. If unset then the
610 default MAC address is used:</p>
612 <li>For the local interface, the default is the lowest-numbered MAC
613 address among the other bridge ports, either the value of the
614 <ref table="Port" column="mac"/> in its <ref table="Port"/> record,
615 if set, or its actual MAC (for bonded ports, the MAC of its slave
616 whose name is first in alphabetical order). Internal ports and
617 bridge ports that are used as port mirroring destinations (see the
618 <ref table="Mirror"/> table) are ignored.</li>
619 <li>For other internal interfaces, the default MAC is randomly
621 <li>External interfaces typically have a MAC address associated with
624 <p>Some interfaces may not have a software-controllable MAC
628 <column name="ofport">
629 <p>OpenFlow port number for this interface. Unlike most columns, this
630 column's value should be set only by Open vSwitch itself. Other
631 clients should set this column to an empty set (the default) when
632 creating an <ref table="Interface"/>.</p>
633 <p>Open vSwitch populates this column when the port number becomes
634 known. If the interface is successfully added,
635 <ref column="ofport"/> will be set to a number between 1 and 65535
636 (generally either in the range 1 to 65279, inclusive, or 65534, the
637 port number for the OpenFlow ``local port''). If the interface
638 cannot be added then Open vSwitch sets this column
643 <group title="System-Specific Details">
645 The interface type, one of:
647 <dt><code>system</code></dt>
648 <dd>An ordinary network device, e.g. <code>eth0</code> on Linux.
649 Sometimes referred to as ``external interfaces'' since they are
650 generally connected to hardware external to that on which the Open
651 vSwitch is running. The empty string is a synonym for
652 <code>system</code>.</dd>
653 <dt><code>internal</code></dt>
654 <dd>A simulated network device that sends and receives traffic. An
655 internal interface whose <ref column="name"/> is the same as its
656 bridge's <ref table="Open_vSwitch" column="name"/> is called the
657 ``local interface.'' It does not make sense to bond an internal
658 interface, so the terms ``port'' and ``interface'' are often used
659 imprecisely for internal interfaces.</dd>
660 <dt><code>tap</code></dt>
661 <dd>A TUN/TAP device managed by Open vSwitch.</dd>
662 <dt><code>gre</code></dt>
663 <dd>An Ethernet over RFC 2890 Generic Routing Encapsulation over IPv4
664 tunnel. Each tunnel must be uniquely identified by the
665 combination of <code>remote_ip</code>, <code>local_ip</code>, and
666 <code>in_key</code>. Note that if two ports are defined that are
667 the same except one has an optional identifier and the other does
668 not, the more specific one is matched first. <code>in_key</code>
669 is considered more specific than <code>local_ip</code> if a port
670 defines one and another port defines the other. The following
671 options may be specified in the <ref column="options"/> column:
673 <dt><code>remote_ip</code></dt>
674 <dd>Required. The tunnel endpoint.</dd>
677 <dt><code>local_ip</code></dt>
678 <dd>Optional. The destination IP that received packets must
679 match. Default is to match all addresses.</dd>
682 <dt><code>in_key</code></dt>
683 <dd>Optional. The GRE key that received packets must contain.
684 It may either be a 32-bit number (no key and a key of 0 are
685 treated as equivalent) or the word <code>flow</code>. If
686 <code>flow</code> is specified then any key will be accepted
687 and the key will be placed in the <code>tun_id</code> field
688 for matching in the flow table. The ovs-ofctl manual page
689 contains additional information about matching fields in
690 OpenFlow flows. Default is no key.</dd>
693 <dt><code>out_key</code></dt>
694 <dd>Optional. The GRE key to be set on outgoing packets. It may
695 either be a 32-bit number or the word <code>flow</code>. If
696 <code>flow</code> is specified then the key may be set using
697 the <code>set_tunnel</code> Nicira OpenFlow vendor extension (0
698 is used in the absence of an action). The ovs-ofctl manual
699 page contains additional information about the Nicira OpenFlow
700 vendor extensions. Default is no key.</dd>
703 <dt><code>key</code></dt>
704 <dd>Optional. Shorthand to set <code>in_key</code> and
705 <code>out_key</code> at the same time.</dd>
708 <dt><code>tos</code></dt>
709 <dd>Optional. The value of the ToS bits to be set on the
710 encapsulating packet. It may also be the word
711 <code>inherit</code>, in which case the ToS will be copied from
712 the inner packet if it is IPv4 or IPv6 (otherwise it will be
713 0). Note that the ECN fields are always inherited. Default is
717 <dt><code>ttl</code></dt>
718 <dd>Optional. The TTL to be set on the encapsulating packet.
719 It may also be the word <code>inherit</code>, in which case the
720 TTL will be copied from the inner packet if it is IPv4 or IPv6
721 (otherwise it will be the system default, typically 64).
722 Default is the system default TTL.</dd>
725 <dt><code>csum</code></dt>
726 <dd>Optional. Compute GRE checksums on outgoing packets.
727 Checksums present on incoming packets will be validated
728 regardless of this setting. Note that GRE checksums
729 impose a significant performance penalty as they cover the
730 entire packet. As the contents of the packet is typically
731 covered by L3 and L4 checksums, this additional checksum only
732 adds value for the GRE and encapsulated Ethernet headers.
733 Default is disabled, set to <code>true</code> to enable.</dd>
736 <dt><code>pmtud</code></dt>
737 <dd>Optional. Enable tunnel path MTU discovery. If enabled
738 ``ICMP destination unreachable - fragmentation'' needed
739 messages will be generated for IPv4 packets with the DF bit set
740 and IPv6 packets above the minimum MTU if the packet size
741 exceeds the path MTU minus the size of the tunnel headers. It
742 also forces the encapsulating packet DF bit to be set (it is
743 always set if the inner packet implies path MTU discovery).
744 Note that this option causes behavior that is typically
745 reserved for routers and therefore is not entirely in
746 compliance with the IEEE 802.1D specification for bridges.
747 Default is enabled, set to <code>false</code> to disable.</dd>
750 <dt><code>header_cache</code></dt>
751 <dd>Optional. Enable caching of tunnel headers and the output
752 path. This can lead to a significant performance increase
753 without changing behavior. In general it should not be
754 necessary to adjust this setting. However, the caching can
755 bypass certain components of the IP stack (such as IP tables)
756 and it may be useful to disable it if these features are
757 required or as a debugging measure. Default is enabled, set to
758 <code>false</code> to disable.</dd>
761 <dt><code>ipsec_gre</code></dt>
762 <dd>An Ethernet over RFC 2890 Generic Routing Encapsulation
763 over IPv4 IPsec tunnel. Each tunnel (including those of type
764 <code>gre</code>) must be uniquely identified by the
765 combination of <code>remote_ip</code> and
766 <code>local_ip</code>. Note that if two ports are defined
767 that are the same except one has an optional identifier and
768 the other does not, the more specific one is matched first.
769 An authentication method of <code>peer_cert</code> or
770 <code>psk</code> must be defined. The following options may
771 be specified in the <ref column="options"/> column:
773 <dt><code>remote_ip</code></dt>
774 <dd>Required. The tunnel endpoint.</dd>
777 <dt><code>local_ip</code></dt>
778 <dd>Optional. The destination IP that received packets must
779 match. Default is to match all addresses.</dd>
782 <dt><code>peer_cert</code></dt>
783 <dd>Required for certificate authentication. A string
784 containing the peer's certificate in PEM format.
785 Additionally the host's certificate must be specified
786 with the <code>certificate</code> option.</dd>
789 <dt><code>certificate</code></dt>
790 <dd>Required for certificate authentication. The name of a
791 PEM file containing a certificate that will be presented
792 to the peer during authentication.</dd>
795 <dt><code>private_key</code></dt>
796 <dd>Optional for certificate authentication. The name of
797 a PEM file containing the private key associated with
798 <code>certificate</code>. If <code>certificate</code>
799 contains the private key, this option may be omitted.</dd>
802 <dt><code>psk</code></dt>
803 <dd>Required for pre-shared key authentication. Specifies a
804 pre-shared key for authentication that must be identical on
805 both sides of the tunnel.</dd>
808 <dt><code>in_key</code></dt>
809 <dd>Optional. The GRE key that received packets must contain.
810 It may either be a 32-bit number (no key and a key of 0 are
811 treated as equivalent) or the word <code>flow</code>. If
812 <code>flow</code> is specified then any key will be accepted
813 and the key will be placed in the <code>tun_id</code> field
814 for matching in the flow table. The ovs-ofctl manual page
815 contains additional information about matching fields in
816 OpenFlow flows. Default is no key.</dd>
819 <dt><code>out_key</code></dt>
820 <dd>Optional. The GRE key to be set on outgoing packets. It may
821 either be a 32-bit number or the word <code>flow</code>. If
822 <code>flow</code> is specified then the key may be set using
823 the <code>set_tunnel</code> Nicira OpenFlow vendor extension (0
824 is used in the absence of an action). The ovs-ofctl manual
825 page contains additional information about the Nicira OpenFlow
826 vendor extensions. Default is no key.</dd>
829 <dt><code>key</code></dt>
830 <dd>Optional. Shorthand to set <code>in_key</code> and
831 <code>out_key</code> at the same time.</dd>
834 <dt><code>tos</code></dt>
835 <dd>Optional. The value of the ToS bits to be set on the
836 encapsulating packet. It may also be the word
837 <code>inherit</code>, in which case the ToS will be copied from
838 the inner packet if it is IPv4 or IPv6 (otherwise it will be
839 0). Note that the ECN fields are always inherited. Default is
843 <dt><code>ttl</code></dt>
844 <dd>Optional. The TTL to be set on the encapsulating packet.
845 It may also be the word <code>inherit</code>, in which case the
846 TTL will be copied from the inner packet if it is IPv4 or IPv6
847 (otherwise it will be the system default, typically 64).
848 Default is the system default TTL.</dd>
851 <dt><code>csum</code></dt>
852 <dd>Optional. Compute GRE checksums on outgoing packets.
853 Checksums present on incoming packets will be validated
854 regardless of this setting. Note that GRE checksums
855 impose a significant performance penalty as they cover the
856 entire packet. As the contents of the packet is typically
857 covered by L3 and L4 checksums, this additional checksum only
858 adds value for the GRE and encapsulated Ethernet headers.
859 Default is disabled, set to <code>true</code> to enable.</dd>
862 <dt><code>pmtud</code></dt>
863 <dd>Optional. Enable tunnel path MTU discovery. If enabled
864 ``ICMP destination unreachable - fragmentation'' needed
865 messages will be generated for IPv4 packets with the DF bit set
866 and IPv6 packets above the minimum MTU if the packet size
867 exceeds the path MTU minus the size of the tunnel headers. It
868 also forces the encapsulating packet DF bit to be set (it is
869 always set if the inner packet implies path MTU discovery).
870 Note that this option causes behavior that is typically
871 reserved for routers and therefore is not entirely in
872 compliance with the IEEE 802.1D specification for bridges.
873 Default is enabled, set to <code>false</code> to disable.</dd>
876 <dt><code>capwap</code></dt>
877 <dd>Ethernet tunneling over the UDP transport portion of CAPWAP
878 (RFC 5415). This allows interoperability with certain switches
879 where GRE is not available. Note that only the tunneling component
880 of the protocol is implemented. Due to the non-standard use of
881 CAPWAP, UDP ports 58881 and 58882 are used as the source and
882 destinations ports respectivedly. Each tunnel must be uniquely
883 identified by the combination of <code>remote_ip</code> and
884 <code>local_ip</code>. If two ports are defined that are the same
885 except one includes <code>local_ip</code> and the other does not,
886 the more specific one is matched first. CAPWAP support is not
887 available on all platforms. Currently it is only supported in the
888 Linux kernel module with kernel versions >= 2.6.25. The following
889 options may be specified in the <ref column="options"/> column:
891 <dt><code>remote_ip</code></dt>
892 <dd>Required. The tunnel endpoint.</dd>
895 <dt><code>local_ip</code></dt>
896 <dd>Optional. The destination IP that received packets must
897 match. Default is to match all addresses.</dd>
900 <dt><code>tos</code></dt>
901 <dd>Optional. The value of the ToS bits to be set on the
902 encapsulating packet. It may also be the word
903 <code>inherit</code>, in which case the ToS will be copied from
904 the inner packet if it is IPv4 or IPv6 (otherwise it will be
905 0). Note that the ECN fields are always inherited. Default is
909 <dt><code>ttl</code></dt>
910 <dd>Optional. The TTL to be set on the encapsulating packet.
911 It may also be the word <code>inherit</code>, in which case the
912 TTL will be copied from the inner packet if it is IPv4 or IPv6
913 (otherwise it will be the system default, typically 64).
914 Default is the system default TTL.</dd>
917 <dt><code>pmtud</code></dt>
918 <dd>Optional. Enable tunnel path MTU discovery. If enabled
919 ``ICMP destination unreachable - fragmentation'' needed
920 messages will be generated for IPv4 packets with the DF bit set
921 and IPv6 packets above the minimum MTU if the packet size
922 exceeds the path MTU minus the size of the tunnel headers. It
923 also forces the encapsulating packet DF bit to be set (it is
924 always set if the inner packet implies path MTU discovery).
925 Note that this option causes behavior that is typically
926 reserved for routers and therefore is not entirely in
927 compliance with the IEEE 802.1D specification for bridges.
928 Default is enabled, set to <code>false</code> to disable.</dd>
931 <dt><code>header_cache</code></dt>
932 <dd>Optional. Enable caching of tunnel headers and the output
933 path. This can lead to a significant performance increase
934 without changing behavior. In general it should not be
935 necessary to adjust this setting. However, the caching can
936 bypass certain components of the IP stack (such as IP tables)
937 and it may be useful to disable it if these features are
938 required or as a debugging measure. Default is enabled, set to
939 <code>false</code> to disable.</dd>
942 <dt><code>patch</code></dt>
945 A pair of virtual devices that act as a patch cable. The <ref
946 column="options"/> column must have the following key-value pair:
949 <dt><code>peer</code></dt>
951 The <ref column="name"/> of the <ref table="Interface"/> for
952 the other side of the patch. The named <ref
953 table="Interface"/>'s own <code>peer</code> option must specify
954 this <ref table="Interface"/>'s name. That is, the two patch
955 interfaces must have reversed <ref column="name"/> and
956 <code>peer</code> values.
963 <column name="options">
964 Configuration options whose interpretation varies based on
965 <ref column="type"/>.
968 <column name="status">
970 Key-value pairs that report port status. Supported status
971 values are <code>type</code>-dependent.
973 <p>The only currently defined key-value pair is:</p>
975 <dt><code>source_ip</code></dt>
976 <dd>The source IP address used for an IPv4 tunnel end-point,
977 such as <code>gre</code> or <code>capwap</code>. Not
978 supported by all implementations.</dd>
983 <group title="Ingress Policing">
985 These settings control ingress policing for packets received on this
986 interface. On a physical interface, this limits the rate at which
987 traffic is allowed into the system from the outside; on a virtual
988 interface (one connected to a virtual machine), this limits the rate at
989 which the VM is able to transmit.
992 Policing is a simple form of quality-of-service that simply drops
993 packets received in excess of the configured rate. Due to its
994 simplicity, policing is usually less accurate and less effective than
995 egress QoS (which is configured using the <ref table="QoS"/> and <ref
996 table="Queue"/> tables).
999 Policing is currently implemented only on Linux. The Linux
1000 implementation uses a simple ``token bucket'' approach:
1004 The size of the bucket corresponds to <ref
1005 column="ingress_policing_burst"/>. Initially the bucket is full.
1008 Whenever a packet is received, its size (converted to tokens) is
1009 compared to the number of tokens currently in the bucket. If the
1010 required number of tokens are available, they are removed and the
1011 packet is forwarded. Otherwise, the packet is dropped.
1014 Whenever it is not full, the bucket is refilled with tokens at the
1015 rate specified by <ref column="ingress_policing_rate"/>.
1019 Policing interacts badly with some network protocols, and especially
1020 with fragmented IP packets. Suppose that there is enough network
1021 activity to keep the bucket nearly empty all the time. Then this token
1022 bucket algorithm will forward a single packet every so often, with the
1023 period depending on packet size and on the configured rate. All of the
1024 fragments of an IP packets are normally transmitted back-to-back, as a
1025 group. In such a situation, therefore, only one of these fragments
1026 will be forwarded and the rest will be dropped. IP does not provide
1027 any way for the intended recipient to ask for only the remaining
1028 fragments. In such a case there are two likely possibilities for what
1029 will happen next: either all of the fragments will eventually be
1030 retransmitted (as TCP will do), in which case the same problem will
1031 recur, or the sender will not realize that its packet has been dropped
1032 and data will simply be lost (as some UDP-based protocols will do).
1033 Either way, it is possible that no forward progress will ever occur.
1035 <column name="ingress_policing_rate">
1037 Maximum rate for data received on this interface, in kbps. Data
1038 received faster than this rate is dropped. Set to <code>0</code>
1039 (the default) to disable policing.
1043 <column name="ingress_policing_burst">
1044 <p>Maximum burst size for data received on this interface, in kb. The
1045 default burst size if set to <code>0</code> is 1000 kb. This value
1046 has no effect if <ref column="ingress_policing_rate"/>
1047 is <code>0</code>.</p>
1049 Specifying a larger burst size lets the algorithm be more forgiving,
1050 which is important for protocols like TCP that react severely to
1051 dropped packets. The burst size should be at least the size of the
1052 interface's MTU. Specifying a value that is numerically at least as
1053 large as 10% of <ref column="ingress_policing_rate"/> helps TCP come
1054 closer to achieving the full rate.
1059 <group title="Other Features">
1061 <column name="monitor">
1062 Connectivity monitor configuration for this interface.
1065 <column name="external_ids">
1066 Key-value pairs for use by external frameworks that integrate
1067 with Open vSwitch, rather than by Open vSwitch itself. System
1068 integrators should either use the Open vSwitch development
1069 mailing list to coordinate on common key-value definitions, or
1070 choose key names that are likely to be unique. The currently
1071 defined common key-value pairs are:
1073 <dt><code>attached-mac</code></dt>
1075 The MAC address programmed into the ``virtual hardware'' for this
1076 interface, in the form
1077 <var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>:<var>xx</var>.
1078 For Citrix XenServer, this is the value of the <code>MAC</code>
1079 field in the VIF record for this interface.</dd>
1080 <dt><code>iface-id</code></dt>
1081 <dd>A system-unique identifier for the interface. On XenServer,
1082 this will commonly be the same as <code>xs-vif-uuid</code>.</dd>
1085 Additionally the following key-value pairs specifically
1086 apply to an interface that represents a virtual Ethernet interface
1087 connected to a virtual machine. These key-value pairs should not be
1088 present for other types of interfaces. Keys whose names end
1089 in <code>-uuid</code> have values that uniquely identify the entity
1090 in question. For a Citrix XenServer hypervisor, these values are
1091 UUIDs in RFC 4122 format. Other hypervisors may use other
1094 <p>The currently defined key-value pairs for XenServer are:</p>
1096 <dt><code>xs-vif-uuid</code></dt>
1097 <dd>The virtual interface associated with this interface.</dd>
1098 <dt><code>xs-network-uuid</code></dt>
1099 <dd>The virtual network to which this interface is attached.</dd>
1100 <dt><code>xs-vm-uuid</code></dt>
1101 <dd>The VM to which this interface belongs.</dd>
1105 <column name="other_config">
1106 Key-value pairs for rarely used interface features. Currently,
1107 there are none defined.
1110 <column name="statistics">
1112 Key-value pairs that report interface statistics. The current
1113 implementation updates these counters periodically. In the future,
1114 we plan to, instead, update them when an interface is created, when
1115 they are queried (e.g. using an OVSDB <code>select</code> operation),
1116 and just before an interface is deleted due to virtual interface
1117 hot-unplug or VM shutdown, and perhaps at other times, but not on any
1118 regular periodic basis.</p>
1120 The currently defined key-value pairs are listed below. These are
1121 the same statistics reported by OpenFlow in its <code>struct
1122 ofp_port_stats</code> structure. If an interface does not support a
1123 given statistic, then that pair is omitted.</p>
1126 Successful transmit and receive counters:
1128 <dt><code>rx_packets</code></dt>
1129 <dd>Number of received packets.</dd>
1130 <dt><code>rx_bytes</code></dt>
1131 <dd>Number of received bytes.</dd>
1132 <dt><code>tx_packets</code></dt>
1133 <dd>Number of transmitted packets.</dd>
1134 <dt><code>tx_bytes</code></dt>
1135 <dd>Number of transmitted bytes.</dd>
1141 <dt><code>rx_dropped</code></dt>
1142 <dd>Number of packets dropped by RX.</dd>
1143 <dt><code>rx_frame_err</code></dt>
1144 <dd>Number of frame alignment errors.</dd>
1145 <dt><code>rx_over_err</code></dt>
1146 <dd>Number of packets with RX overrun.</dd>
1147 <dt><code>rx_crc_err</code></dt>
1148 <dd>Number of CRC errors.</dd>
1149 <dt><code>rx_errors</code></dt>
1151 Total number of receive errors, greater than or equal
1152 to the sum of the above.
1159 <dt><code>tx_dropped</code></dt>
1160 <dd>Number of packets dropped by TX.</dd>
1161 <dt><code>collisions</code></dt>
1162 <dd>Number of collisions.</dd>
1163 <dt><code>tx_errors</code></dt>
1165 Total number of transmit errors, greater
1166 than or equal to the sum of the above.
1175 <table name="QoS" title="Quality of Service configuration">
1176 <p>Quality of Service (QoS) configuration for each Port that
1179 <column name="type">
1180 <p>The type of QoS to implement. The <ref table="Open_vSwitch"
1181 column="capabilities"/> column in the <ref table="Open_vSwitch"/> table
1182 identifies the types that a switch actually supports. The currently
1183 defined types are listed below:</p>
1185 <dt><code>linux-htb</code></dt>
1187 Linux ``hierarchy token bucket'' classifier. See tc-htb(8) (also at
1188 <code>http://linux.die.net/man/8/tc-htb</code>) and the HTB manual
1189 (<code>http://luxik.cdi.cz/~devik/qos/htb/manual/userg.htm</code>)
1190 for information on how this classifier works and how to configure it.
1194 <dt><code>linux-hfsc</code></dt>
1196 Linux "Hierarchical Fair Service Curve" classifier.
1197 See <code>http://linux-ip.net/articles/hfsc.en/</code> for
1198 information on how this classifier works.
1203 <column name="queues">
1204 <p>A map from queue numbers to <ref table="Queue"/> records. The
1205 supported range of queue numbers depend on <ref column="type"/>. The
1206 queue numbers are the same as the <code>queue_id</code> used in
1207 OpenFlow in <code>struct ofp_action_enqueue</code> and other
1208 structures. Queue 0 is used by OpenFlow output actions that do not
1209 specify a specific queue.</p>
1212 <column name="other_config">
1213 <p>Key-value pairs for configuring QoS features that depend on
1214 <ref column="type"/>.</p>
1215 <p>The <code>linux-htb</code> and <code>linux-hfsc</code> classes support
1216 the following key-value pairs:</p>
1218 <dt><code>max-rate</code></dt>
1219 <dd>Maximum rate shared by all queued traffic, in bit/s.
1220 Optional. If not specified, for physical interfaces, the
1221 default is the link rate. For other interfaces or if the
1222 link rate cannot be determined, the default is currently 100
1227 <column name="external_ids">
1228 Key-value pairs for use by external frameworks that integrate with Open
1229 vSwitch, rather than by Open vSwitch itself. System integrators should
1230 either use the Open vSwitch development mailing list to coordinate on
1231 common key-value definitions, or choose key names that are likely to be
1232 unique. No common key-value pairs are currently defined.
1236 <table name="Queue" title="QoS output queue.">
1237 <p>A configuration for a port output queue, used in configuring Quality of
1238 Service (QoS) features. May be referenced by <ref column="queues"
1239 table="QoS"/> column in <ref table="QoS"/> table.</p>
1241 <column name="other_config">
1242 <p>Key-value pairs for configuring the output queue. The supported
1243 key-value pairs and their meanings depend on the <ref column="type"/>
1244 of the <ref column="QoS"/> records that reference this row.</p>
1245 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1246 column="type"/> of <code>min-rate</code> are:</p>
1248 <dt><code>min-rate</code></dt>
1249 <dd>Minimum guaranteed bandwidth, in bit/s. Required. The
1250 floor value is 1500 bytes/s (12,000 bit/s).</dd>
1252 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1253 column="type"/> of <code>linux-htb</code> are:</p>
1255 <dt><code>min-rate</code></dt>
1256 <dd>Minimum guaranteed bandwidth, in bit/s. Required.</dd>
1257 <dt><code>max-rate</code></dt>
1258 <dd>Maximum allowed bandwidth, in bit/s. Optional. If specified, the
1259 queue's rate will not be allowed to exceed the specified value, even
1260 if excess bandwidth is available. If unspecified, defaults to no
1262 <dt><code>burst</code></dt>
1263 <dd>Burst size, in bits. This is the maximum amount of ``credits''
1264 that a queue can accumulate while it is idle. Optional. Details of
1265 the <code>linux-htb</code> implementation require a minimum burst
1266 size, so a too-small <code>burst</code> will be silently
1268 <dt><code>priority</code></dt>
1269 <dd>A nonnegative 32-bit integer. Defaults to 0 if
1270 unspecified. A queue with a smaller <code>priority</code>
1271 will receive all the excess bandwidth that it can use before
1272 a queue with a larger value receives any. Specific priority
1273 values are unimportant; only relative ordering matters.</dd>
1275 <p>The key-value pairs defined for <ref table="QoS"/> <ref table="QoS"
1276 column="type"/> of <code>linux-hfsc</code> are:</p>
1278 <dt><code>min-rate</code></dt>
1279 <dd>Minimum guaranteed bandwidth, in bit/s. Required.</dd>
1280 <dt><code>max-rate</code></dt>
1281 <dd>Maximum allowed bandwidth, in bit/s. Optional. If specified, the
1282 queue's rate will not be allowed to exceed the specified value, even
1283 if excess bandwidth is available. If unspecified, defaults to no
1288 <column name="external_ids">
1289 Key-value pairs for use by external frameworks that integrate with Open
1290 vSwitch, rather than by Open vSwitch itself. System integrators should
1291 either use the Open vSwitch development mailing list to coordinate on
1292 common key-value definitions, or choose key names that are likely to be
1293 unique. No common key-value pairs are currently defined.
1297 <table name="Monitor" title="Connectivity Monitor configuration">
1299 A <ref table="Monitor"/> attaches to an <ref table="Interface"/> to
1300 implement 802.1ag Connectivity Fault Management (CFM). CFM allows a
1301 group of Maintenance Points (MPs) called a Maintenance Association (MA)
1302 to detect connectivity problems with each other. MPs within a MA should
1303 have complete and exclusive interconnectivity. This is verified by
1304 occasionally broadcasting Continuity Check Messages (CCMs) at a
1305 configurable transmission interval. A <ref table="Monitor"/> is
1306 responsible for collecting data about other MPs in its MA and
1310 <group title="Monitor Configuration">
1311 <column name="mpid">
1312 A Maintenance Point ID (MPID) uniquely identifies each endpoint within
1313 a Maintenance Association (see <ref column="ma_name"/>). The MPID is
1314 used to identify this <ref table="Monitor"/> to other endpoints in the
1318 <column name="remote_mps">
1319 A set of <ref table="Maintenance_Points"/> which this
1320 <ref table="Monitor"/> should have connectivity to. If this
1321 <ref table="Monitor"/> does not have connectivity to any MPs in this
1322 set, or has connectivity to any MPs not in this set, a fault is
1326 <column name="ma_name">
1327 A Maintenance Association (MA) name pairs with a Maintenance Domain
1328 (MD) name to uniquely identify a MA. A MA is a group of endpoints who
1329 have complete and exclusive interconnectivity. Defaults to
1330 <code>ovs</code> if unset.
1333 <column name="md_name">
1334 A Maintenance Domain name pairs with a Maintenance Association name to
1335 uniquely identify a MA. Defaults to <code>ovs</code> if unset.
1338 <column name="interval">
1339 The transmission interval of CCMs in milliseconds. Three missed CCMs
1340 indicate a connectivity fault. Defaults to 1000ms.
1344 <group title="Monitor Status">
1345 <column name="unexpected_remote_mpids">
1346 A set of MPIDs representing MPs to which this <ref table="Monitor"/>
1347 has detected connectivity that are not in the
1348 <ref column="remote_mps"/> set. This <ref table="Monitor"/> should not
1349 have connectivity to any MPs not listed in <ref column="remote_mps"/>.
1350 Thus, if this set is non-empty a fault is indicated.
1353 <column name="unexpected_remote_maids">
1354 A set of MAIDs representing foreign Maintenance Associations (MAs)
1355 which this <ref table="Monitor"/> has detected connectivity to. A
1356 <ref table="Monitor"/> should not have connectivity to a Maintenance
1357 Association other than its own. Thus, if this set is non-empty a fault
1361 <column name="fault">
1362 Indicates a Connectivity Fault caused by a configuration error, a down
1363 remote MP, or unexpected connectivity to a remote MAID or remote MP.
1368 <table name="Maintenance_Point" title="Maintenance Point configuration">
1370 A <ref table="Maintenance_Point"/> represents a MP which a
1371 <ref table="Monitor"/> has or should have connectivity to.
1374 <group title="Maintenance_Point Configuration">
1375 <column name="mpid">
1376 A Maintenance Point ID (MPID) uniquely identifies each endpoint within
1377 a Maintenance Association. All MPs within a MA should have a unique
1382 <group title="Maintenance_Point Status">
1383 <column name="fault">
1384 Indicates a connectivity fault.
1389 <table name="Mirror" title="Port mirroring (SPAN/RSPAN).">
1390 <p>A port mirror within a <ref table="Bridge"/>.</p>
1391 <p>A port mirror configures a bridge to send selected frames to special
1392 ``mirrored'' ports, in addition to their normal destinations. Mirroring
1393 traffic may also be referred to as SPAN or RSPAN, depending on the
1394 mechanism used for delivery.</p>
1396 <column name="name">
1397 Arbitrary identifier for the <ref table="Mirror"/>.
1400 <group title="Selecting Packets for Mirroring">
1401 <column name="select_all">
1402 If true, every packet arriving or departing on any port is
1403 selected for mirroring.
1406 <column name="select_dst_port">
1407 Ports on which departing packets are selected for mirroring.
1410 <column name="select_src_port">
1411 Ports on which arriving packets are selected for mirroring.
1414 <column name="select_vlan">
1415 VLANs on which packets are selected for mirroring. An empty set
1416 selects packets on all VLANs.
1420 <group title="Mirroring Destination Configuration">
1421 <column name="output_port">
1422 <p>Output port for selected packets, if nonempty. Mutually exclusive
1423 with <ref column="output_vlan"/>.</p>
1424 <p>Specifying a port for mirror output reserves that port exclusively
1425 for mirroring. No frames other than those selected for mirroring
1426 will be forwarded to the port, and any frames received on the port
1427 will be discarded.</p>
1428 <p>This type of mirroring is sometimes called SPAN.</p>
1431 <column name="output_vlan">
1432 <p>Output VLAN for selected packets, if nonempty. Mutually exclusive
1433 with <ref column="output_port"/>.</p>
1434 <p>The frames will be sent out all ports that trunk
1435 <ref column="output_vlan"/>, as well as any ports with implicit VLAN
1436 <ref column="output_vlan"/>. When a mirrored frame is sent out a
1437 trunk port, the frame's VLAN tag will be set to
1438 <ref column="output_vlan"/>, replacing any existing tag; when it is
1439 sent out an implicit VLAN port, the frame will not be tagged. This
1440 type of mirroring is sometimes called RSPAN.</p>
1441 <p><em>Please note:</em> Mirroring to a VLAN can disrupt a network that
1442 contains unmanaged switches. Consider an unmanaged physical switch
1443 with two ports: port 1, connected to an end host, and port 2,
1444 connected to an Open vSwitch configured to mirror received packets
1445 into VLAN 123 on port 2. Suppose that the end host sends a packet on
1446 port 1 that the physical switch forwards to port 2. The Open vSwitch
1447 forwards this packet to its destination and then reflects it back on
1448 port 2 in VLAN 123. This reflected packet causes the unmanaged
1449 physical switch to replace the MAC learning table entry, which
1450 correctly pointed to port 1, with one that incorrectly points to port
1451 2. Afterward, the physical switch will direct packets destined for
1452 the end host to the Open vSwitch on port 2, instead of to the end
1453 host on port 1, disrupting connectivity. If mirroring to a VLAN is
1454 desired in this scenario, then the physical switch must be replaced
1455 by one that learns Ethernet addresses on a per-VLAN basis. In
1456 addition, learning should be disabled on the VLAN containing mirrored
1457 traffic. If this is not done then intermediate switches will learn
1458 the MAC address of each end host from the mirrored traffic. If
1459 packets being sent to that end host are also mirrored, then they will
1460 be dropped since the switch will attempt to send them out the input
1461 port. Disabling learning for the VLAN will cause the switch to
1462 correctly send the packet out all ports configured for that VLAN. If
1463 Open vSwitch is being used as an intermediate switch, learning can be
1464 disabled by adding the mirrored VLAN to <ref column="flood_vlans"/>
1465 in the appropriate <ref table="Bridge"/> table or tables.</p>
1469 <group title="Other Features">
1470 <column name="external_ids">
1471 Key-value pairs for use by external frameworks that integrate with Open
1472 vSwitch, rather than by Open vSwitch itself. System integrators should
1473 either use the Open vSwitch development mailing list to coordinate on
1474 common key-value definitions, or choose key names that are likely to be
1475 unique. No common key-value pairs are currently defined.
1480 <table name="Controller" title="OpenFlow controller configuration.">
1481 <p>An OpenFlow controller.</p>
1484 Open vSwitch supports two kinds of OpenFlow controllers:
1488 <dt>Primary controllers</dt>
1491 This is the kind of controller envisioned by the OpenFlow 1.0
1492 specification. Usually, a primary controller implements a network
1493 policy by taking charge of the switch's flow table.
1497 Open vSwitch initiates and maintains persistent connections to
1498 primary controllers, retrying the connection each time it fails or
1499 drops. The <ref table="Bridge" column="fail_mode"/> column in the
1500 <ref table="Bridge"/> table applies to primary controllers.
1504 Open vSwitch permits a bridge to have any number of primary
1505 controllers. When multiple controllers are configured, Open
1506 vSwitch connects to all of them simultaneously. Because
1507 OpenFlow 1.0 does not specify how multiple controllers
1508 coordinate in interacting with a single switch, more than
1509 one primary controller should be specified only if the
1510 controllers are themselves designed to coordinate with each
1511 other. (The Nicira-defined <code>NXT_ROLE</code> OpenFlow
1512 vendor extension may be useful for this.)
1515 <dt>Service controllers</dt>
1518 These kinds of OpenFlow controller connections are intended for
1519 occasional support and maintenance use, e.g. with
1520 <code>ovs-ofctl</code>. Usually a service controller connects only
1521 briefly to inspect or modify some of a switch's state.
1525 Open vSwitch listens for incoming connections from service
1526 controllers. The service controllers initiate and, if necessary,
1527 maintain the connections from their end. The <ref table="Bridge"
1528 column="fail_mode"/> column in the <ref table="Bridge"/> table does
1529 not apply to service controllers.
1533 Open vSwitch supports configuring any number of service controllers.
1539 The <ref column="target"/> determines the type of controller.
1542 <group title="Core Features">
1543 <column name="target">
1544 <p>Connection method for controller.</p>
1546 The following connection methods are currently supported for primary
1550 <dt><code>ssl:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1552 <p>The specified SSL <var>port</var> (default: 6633) on the host at
1553 the given <var>ip</var>, which must be expressed as an IP address
1554 (not a DNS name). The <ref table="Open_vSwitch" column="ssl"/>
1555 column in the <ref table="Open_vSwitch"/> table must point to a
1556 valid SSL configuration when this form is used.</p>
1557 <p>SSL support is an optional feature that is not always built as
1558 part of Open vSwitch.</p>
1560 <dt><code>tcp:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1561 <dd>The specified TCP <var>port</var> (default: 6633) on the host at
1562 the given <var>ip</var>, which must be expressed as an IP address
1563 (not a DNS name).</dd>
1564 <dt><code>discover</code></dt>
1566 <p>Enables controller discovery.</p>
1567 <p>In controller discovery mode, Open vSwitch broadcasts a DHCP
1568 request with vendor class identifier <code>OpenFlow</code> across
1569 all of the bridge's network devices. It will accept any valid
1570 DHCP reply that has the same vendor class identifier and includes
1571 a vendor-specific option with code 1 whose contents are a string
1572 specifying the location of the controller in the same format as
1573 <ref column="target"/>.</p>
1574 <p>The DHCP reply may also, optionally, include a vendor-specific
1575 option with code 2 whose contents are a string specifying the URI
1576 to the base of the OpenFlow PKI
1577 (e.g. <code>http://192.168.0.1/openflow/pki</code>). This URI is
1578 used only for bootstrapping the OpenFlow PKI at initial switch
1579 setup; <code>ovs-vswitchd</code> does not use it at all.</p>
1583 The following connection methods are currently supported for service
1587 <dt><code>pssl:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1590 Listens for SSL connections on the specified TCP <var>port</var>
1591 (default: 6633). If <var>ip</var>, which must be expressed as an
1592 IP address (not a DNS name), is specified, then connections are
1593 restricted to the specified local IP address.
1596 The <ref table="Open_vSwitch" column="ssl"/> column in the <ref
1597 table="Open_vSwitch"/> table must point to a valid SSL
1598 configuration when this form is used.
1600 <p>SSL support is an optional feature that is not always built as
1601 part of Open vSwitch.</p>
1603 <dt><code>ptcp:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1605 Listens for connections on the specified TCP <var>port</var>
1606 (default: 6633). If <var>ip</var>, which must be expressed as an
1607 IP address (not a DNS name), is specified, then connections are
1608 restricted to the specified local IP address.
1611 <p>When multiple controllers are configured for a single bridge, the
1612 <ref column="target"/> values must be unique. Duplicate
1613 <ref column="target"/> values yield unspecified results.</p>
1616 <column name="connection_mode">
1617 <p>If it is specified, this setting must be one of the following
1618 strings that describes how Open vSwitch contacts this OpenFlow
1619 controller over the network:</p>
1622 <dt><code>in-band</code></dt>
1623 <dd>In this mode, this controller's OpenFlow traffic travels over the
1624 bridge associated with the controller. With this setting, Open
1625 vSwitch allows traffic to and from the controller regardless of the
1626 contents of the OpenFlow flow table. (Otherwise, Open vSwitch
1627 would never be able to connect to the controller, because it did
1628 not have a flow to enable it.) This is the most common connection
1629 mode because it is not necessary to maintain two independent
1631 <dt><code>out-of-band</code></dt>
1632 <dd>In this mode, OpenFlow traffic uses a control network separate
1633 from the bridge associated with this controller, that is, the
1634 bridge does not use any of its own network devices to communicate
1635 with the controller. The control network must be configured
1636 separately, before or after <code>ovs-vswitchd</code> is started.
1640 <p>If not specified, the default is implementation-specific. If
1641 <ref column="target"/> is <code>discover</code>, the connection mode
1642 is always treated as <code>in-band</code> regardless of the actual
1647 <group title="Controller Failure Detection and Handling">
1648 <column name="max_backoff">
1649 Maximum number of milliseconds to wait between connection attempts.
1650 Default is implementation-specific.
1653 <column name="inactivity_probe">
1654 Maximum number of milliseconds of idle time on connection to
1655 controller before sending an inactivity probe message. If Open
1656 vSwitch does not communicate with the controller for the specified
1657 number of seconds, it will send a probe. If a response is not
1658 received for the same additional amount of time, Open vSwitch
1659 assumes the connection has been broken and attempts to reconnect.
1660 Default is implementation-specific.
1664 <group title="OpenFlow Rate Limiting">
1665 <column name="controller_rate_limit">
1666 <p>The maximum rate at which packets in unknown flows will be
1667 forwarded to the OpenFlow controller, in packets per second. This
1668 feature prevents a single bridge from overwhelming the controller.
1669 If not specified, the default is implementation-specific.</p>
1670 <p>In addition, when a high rate triggers rate-limiting, Open
1671 vSwitch queues controller packets for each port and transmits
1672 them to the controller at the configured rate. The number of
1673 queued packets is limited by
1674 the <ref column="controller_burst_limit"/> value. The packet
1675 queue is shared fairly among the ports on a bridge.</p><p>Open
1676 vSwitch maintains two such packet rate-limiters per bridge.
1677 One of these applies to packets sent up to the controller
1678 because they do not correspond to any flow. The other applies
1679 to packets sent up to the controller by request through flow
1680 actions. When both rate-limiters are filled with packets, the
1681 actual rate that packets are sent to the controller is up to
1682 twice the specified rate.</p>
1685 <column name="controller_burst_limit">
1686 In conjunction with <ref column="controller_rate_limit"/>,
1687 the maximum number of unused packet credits that the bridge will
1688 allow to accumulate, in packets. If not specified, the default
1689 is implementation-specific.
1693 <group title="Additional Discovery Configuration">
1694 <p>These values are considered only when <ref column="target"/>
1695 is <code>discover</code>.</p>
1697 <column name="discover_accept_regex">
1699 extended regular expression against which the discovered controller
1700 location is validated. The regular expression is implicitly
1701 anchored at the beginning of the controller location string, as
1702 if it begins with <code>^</code>. If not specified, the default
1703 is implementation-specific.
1706 <column name="discover_update_resolv_conf">
1707 Whether to update <code>/etc/resolv.conf</code> when the
1708 controller is discovered. If not specified, the default
1709 is implementation-specific. Open vSwitch will only modify
1710 <code>/etc/resolv.conf</code> if the DHCP response that it receives
1711 specifies one or more DNS servers.
1715 <group title="Additional In-Band Configuration">
1716 <p>These values are considered only in in-band control mode (see
1717 <ref column="connection_mode"/>) and only when <ref column="target"/>
1718 is not <code>discover</code>. (For controller discovery, the network
1719 configuration obtained via DHCP is used instead.)</p>
1721 <p>When multiple controllers are configured on a single bridge, there
1722 should be only one set of unique values in these columns. If different
1723 values are set for these columns in different controllers, the effect
1726 <column name="local_ip">
1727 The IP address to configure on the local port,
1728 e.g. <code>192.168.0.123</code>. If this value is unset, then
1729 <ref column="local_netmask"/> and <ref column="local_gateway"/> are
1733 <column name="local_netmask">
1734 The IP netmask to configure on the local port,
1735 e.g. <code>255.255.255.0</code>. If <ref column="local_ip"/> is set
1736 but this value is unset, then the default is chosen based on whether
1737 the IP address is class A, B, or C.
1740 <column name="local_gateway">
1741 The IP address of the gateway to configure on the local port, as a
1742 string, e.g. <code>192.168.0.1</code>. Leave this column unset if
1743 this network has no gateway.
1747 <group title="Other Features">
1748 <column name="external_ids">
1749 Key-value pairs for use by external frameworks that integrate with Open
1750 vSwitch, rather than by Open vSwitch itself. System integrators should
1751 either use the Open vSwitch development mailing list to coordinate on
1752 common key-value definitions, or choose key names that are likely to be
1753 unique. No common key-value pairs are currently defined.
1758 <table name="Manager" title="OVSDB management connection.">
1760 Configuration for a database connection to an Open vSwitch database
1765 This table primarily configures the Open vSwitch database
1766 (<code>ovsdb-server</code>), not the Open vSwitch switch
1767 (<code>ovs-vswitchd</code>). The switch does read the table to determine
1768 what connections should be treated as in-band.
1772 The Open vSwitch database server can initiate and maintain active
1773 connections to remote clients. It can also listen for database
1777 <group title="Core Features">
1778 <column name="target">
1779 <p>Connection method for managers.</p>
1781 The following connection methods are currently supported:
1784 <dt><code>ssl:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1787 The specified SSL <var>port</var> (default: 6632) on the host at
1788 the given <var>ip</var>, which must be expressed as an IP address
1789 (not a DNS name). The <ref table="Open_vSwitch" column="ssl"/>
1790 column in the <ref table="Open_vSwitch"/> table must point to a
1791 valid SSL configuration when this form is used.
1794 SSL support is an optional feature that is not always built as
1795 part of Open vSwitch.
1799 <dt><code>tcp:<var>ip</var></code>[<code>:<var>port</var></code>]</dt>
1801 The specified TCP <var>port</var> (default: 6632) on the host at
1802 the given <var>ip</var>, which must be expressed as an IP address
1805 <dt><code>pssl:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1808 Listens for SSL connections on the specified TCP <var>port</var>
1809 (default: 6632). If <var>ip</var>, which must be expressed as an
1810 IP address (not a DNS name), is specified, then connections are
1811 restricted to the specified local IP address.
1814 The <ref table="Open_vSwitch" column="ssl"/> column in the <ref
1815 table="Open_vSwitch"/> table must point to a valid SSL
1816 configuration when this form is used.
1819 SSL support is an optional feature that is not always built as
1820 part of Open vSwitch.
1823 <dt><code>ptcp:</code>[<var>port</var>][<code>:<var>ip</var></code>]</dt>
1825 Listens for connections on the specified TCP <var>port</var>
1826 (default: 6632). If <var>ip</var>, which must be expressed as an
1827 IP address (not a DNS name), is specified, then connections are
1828 restricted to the specified local IP address.
1831 <p>When multiple managers are configured, the <ref column="target"/>
1832 values must be unique. Duplicate <ref column="target"/> values yield
1833 unspecified results.</p>
1836 <column name="connection_mode">
1838 If it is specified, this setting must be one of the following strings
1839 that describes how Open vSwitch contacts this OVSDB client over the
1844 <dt><code>in-band</code></dt>
1846 In this mode, this connection's traffic travels over a bridge
1847 managed by Open vSwitch. With this setting, Open vSwitch allows
1848 traffic to and from the client regardless of the contents of the
1849 OpenFlow flow table. (Otherwise, Open vSwitch would never be able
1850 to connect to the client, because it did not have a flow to enable
1851 it.) This is the most common connection mode because it is not
1852 necessary to maintain two independent networks.
1854 <dt><code>out-of-band</code></dt>
1856 In this mode, the client's traffic uses a control network separate
1857 from that managed by Open vSwitch, that is, Open vSwitch does not
1858 use any of its own network devices to communicate with the client.
1859 The control network must be configured separately, before or after
1860 <code>ovs-vswitchd</code> is started.
1865 If not specified, the default is implementation-specific.
1870 <group title="Client Failure Detection and Handling">
1871 <column name="max_backoff">
1872 Maximum number of milliseconds to wait between connection attempts.
1873 Default is implementation-specific.
1876 <column name="inactivity_probe">
1877 Maximum number of milliseconds of idle time on connection to the client
1878 before sending an inactivity probe message. If Open vSwitch does not
1879 communicate with the client for the specified number of seconds, it
1880 will send a probe. If a response is not received for the same
1881 additional amount of time, Open vSwitch assumes the connection has been
1882 broken and attempts to reconnect. Default is implementation-specific.
1886 <group title="Other Features">
1887 <column name="external_ids">
1888 Key-value pairs for use by external frameworks that integrate with Open
1889 vSwitch, rather than by Open vSwitch itself. System integrators should
1890 either use the Open vSwitch development mailing list to coordinate on
1891 common key-value definitions, or choose key names that are likely to be
1892 unique. No common key-value pairs are currently defined.
1897 <table name="NetFlow">
1898 A NetFlow target. NetFlow is a protocol that exports a number of
1899 details about terminating IP flows, such as the principals involved
1902 <column name="targets">
1903 NetFlow targets in the form
1904 <code><var>ip</var>:<var>port</var></code>. The <var>ip</var>
1905 must be specified numerically, not as a DNS name.
1908 <column name="engine_id">
1909 Engine ID to use in NetFlow messages. Defaults to datapath index
1913 <column name="engine_type">
1914 Engine type to use in NetFlow messages. Defaults to datapath
1915 index if not specified.
1918 <column name="active_timeout">
1919 The interval at which NetFlow records are sent for flows that are
1920 still active, in seconds. A value of <code>0</code> requests the
1921 default timeout (currently 600 seconds); a value of <code>-1</code>
1922 disables active timeouts.
1925 <column name="add_id_to_interface">
1926 <p>If this column's value is <code>false</code>, the ingress and egress
1927 interface fields of NetFlow flow records are derived from OpenFlow port
1928 numbers. When it is <code>true</code>, the 7 most significant bits of
1929 these fields will be replaced by the least significant 7 bits of the
1930 engine id. This is useful because many NetFlow collectors do not
1931 expect multiple switches to be sending messages from the same host, so
1932 they do not store the engine information which could be used to
1933 disambiguate the traffic.</p>
1934 <p>When this option is enabled, a maximum of 508 ports are supported.</p>
1937 <column name="external_ids">
1938 Key-value pairs for use by external frameworks that integrate with Open
1939 vSwitch, rather than by Open vSwitch itself. System integrators should
1940 either use the Open vSwitch development mailing list to coordinate on
1941 common key-value definitions, or choose key names that are likely to be
1942 unique. No common key-value pairs are currently defined.
1947 SSL configuration for an Open_vSwitch.
1949 <column name="private_key">
1950 Name of a PEM file containing the private key used as the switch's
1951 identity for SSL connections to the controller.
1954 <column name="certificate">
1955 Name of a PEM file containing a certificate, signed by the
1956 certificate authority (CA) used by the controller and manager,
1957 that certifies the switch's private key, identifying a trustworthy
1961 <column name="ca_cert">
1962 Name of a PEM file containing the CA certificate used to verify
1963 that the switch is connected to a trustworthy controller.
1966 <column name="bootstrap_ca_cert">
1967 If set to <code>true</code>, then Open vSwitch will attempt to
1968 obtain the CA certificate from the controller on its first SSL
1969 connection and save it to the named PEM file. If it is successful,
1970 it will immediately drop the connection and reconnect, and from then
1971 on all SSL connections must be authenticated by a certificate signed
1972 by the CA certificate thus obtained. <em>This option exposes the
1973 SSL connection to a man-in-the-middle attack obtaining the initial
1974 CA certificate.</em> It may still be useful for bootstrapping.
1977 <column name="external_ids">
1978 Key-value pairs for use by external frameworks that integrate with Open
1979 vSwitch, rather than by Open vSwitch itself. System integrators should
1980 either use the Open vSwitch development mailing list to coordinate on
1981 common key-value definitions, or choose key names that are likely to be
1982 unique. No common key-value pairs are currently defined.
1986 <table name="sFlow">
1987 <p>An sFlow(R) target. sFlow is a protocol for remote monitoring
1990 <column name="agent">
1991 Name of the network device whose IP address should be reported as the
1992 ``agent address'' to collectors. If not specified, the IP address
1993 defaults to the <ref table="Controller" column="local_ip"/> in the
1994 collector's <ref table="Controller"/>. If an agent IP address cannot be
1995 determined either way, sFlow is disabled.
1998 <column name="header">
1999 Number of bytes of a sampled packet to send to the collector.
2000 If not specified, the default is 128 bytes.
2003 <column name="polling">
2004 Polling rate in seconds to send port statistics to the collector.
2005 If not specified, defaults to 30 seconds.
2008 <column name="sampling">
2009 Rate at which packets should be sampled and sent to the collector.
2010 If not specified, defaults to 400, which means one out of 400
2011 packets, on average, will be sent to the collector.
2014 <column name="targets">
2015 sFlow targets in the form
2016 <code><var>ip</var>:<var>port</var></code>.
2019 <column name="external_ids">
2020 Key-value pairs for use by external frameworks that integrate with Open
2021 vSwitch, rather than by Open vSwitch itself. System integrators should
2022 either use the Open vSwitch development mailing list to coordinate on
2023 common key-value definitions, or choose key names that are likely to be
2024 unique. No common key-value pairs are currently defined.
2028 <table name="Capability">
2029 <p>Records in this table describe functionality supported by the hardware
2030 and software platform on which this Open vSwitch is based. Clients
2031 should not modify this table.</p>
2033 <p>A record in this table is meaningful only if it is referenced by the
2034 <ref table="Open_vSwitch" column="capabilities"/> column in the
2035 <ref table="Open_vSwitch"/> table. The key used to reference it, called
2036 the record's ``category,'' determines the meanings of the
2037 <ref column="details"/> column. The following general forms of
2038 categories are currently defined:</p>
2041 <dt><code>qos-<var>type</var></code></dt>
2042 <dd><var>type</var> is supported as the value for
2043 <ref column="type" table="QoS"/> in the <ref table="QoS"/> table.
2047 <column name="details">
2048 <p>Key-value pairs that describe capabilities. The meaning of the pairs
2049 depends on the category key that the <ref table="Open_vSwitch"
2050 column="capabilities"/> column in the <ref table="Open_vSwitch"/> table
2051 uses to reference this record, as described above.</p>
2053 <p>The presence of a record for category <code>qos-<var>type</var></code>
2054 indicates that the switch supports <var>type</var> as the value of
2055 the <ref table="QoS" column="type"/> column in the <ref table="QoS"/>
2056 table. The following key-value pairs are defined to further describe
2057 QoS capabilities:</p>
2060 <dt><code>n-queues</code></dt>
2061 <dd>Number of supported queues, as a positive integer. Keys in the
2062 <ref table="QoS" column="queues"/> column for <ref table="QoS"/>
2063 records whose <ref table="QoS" column="type"/> value
2064 equals <var>type</var> must range between 0 and this value minus one,