ovsdb-server(5) — Linux manual page


ovsdb-server(5)              Open vSwitch Manual             ovsdb-server(5)

NAME         top

       ovsdb-server - _Server database schema

       Every ovsdb-server (version 2.9 or later) always hosts an instance of
       this schema, which holds information on the status and  configuration
       of  the  server  itself.  This  database  is  read-only. This manpage
       describes the schema for this database.

TABLE SUMMARY         top

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

       Table     Purpose
       Database  Databases.

Database TABLE         top

       This table describes the databases hosted by the database server,
       with one row per database. As its database configuration and status
       changes, the server automatically and immediately updates the table
       to match.

       The OVSDB protocol specified in RFC 7047 does not provide a way for
       an OVSDB client to find out about some kinds of configuration
       changes, such as about databases added or removed while a client is
       connected to the server, or databases changing between read/write and
       read-only due to a transition between active and backup roles. This
       table provides a solution: clients can monitor the table’s contents
       to find out about important changes.

       Traditionally, ovsdb-server disconnects all of its clients when a
       significant configuration change occurs, because this prompts a well-
       written client to reassess what is available from the server when it
       reconnects. Because this table provides an alternative and more
       efficient way to find out about those changes, OVS 2.9 also
       introduces the set_db_change_aware RPC, documented in
       ovsdb-server(7), to allow clients to suppress this disconnection

       When a database is removed from the server, in addition to Database
       table updates, the server sends canceled messages, as described in
       RFC 7047 section 4.1.4, in reply to outstanding transactions for the
       removed database. The server also cancels any outstanding monitoring
       initiated by monitor or monitor_cond requested on the removed
       database, sending the monitor_canceled RPC described in
       ovsdb-server(7). Only clients that disable disconnection with
       set_db_change_aware receive these messages.

       Clients can use the _uuid column in this table as a generation
       number. The server generates a fresh _uuid every time it adds a
       database, so that removing and then re-adding a database to the
       server causes its row _uuid to change.

       name                          string
       model                         string, either clustered or standalone
       schema                        optional string
       Clustered Databases:
         connected                   boolean
         leader                      boolean
         cid                         optional uuid
         sid                         optional uuid
         index                       optional integer

       name: string
              The database’s name, as specified in its schema.

       model: string, either clustered or standalone
              The storage model: standalone for a standalone or active-
              backup database, clustered for a clustered database.

       schema: optional string
              The database schema, as a JSON string. In the case of a
              clustered database, this is empty until it finishes joining
              its cluster.

     Clustered Databases:

       These columns are most interesting and in some cases only relevant
       for clustered databases, that is, those where the model column is

       connected: boolean
              True if the database is connected to its storage. A standalone
              or active-backup database is always connected. A clustered
              database is connected if the server is in contact with a
              majority of its cluster. An unconnected database cannot be
              modified and its data might be unavailable or stale.

       leader: boolean
              True if the database is the leader in its cluster. For a
              standalone or active-backup database, this is always true.

       cid: optional uuid
              The cluster ID for this database, which is the same for all of
              the servers that host this particular clustered database. For
              a standalone or active-backup database, this is empty.

       sid: optional uuid
              The server ID for this database, different for each server
              that hosts a particular clustered database. A server that
              hosts more than one clustered database will have a different
              sid in each one. For a standalone or active-backup database,
              this is empty.

       index: optional integer
              For a clustered database, the index of the log entry currently
              exposed to clients. For a given server, this increases
              monotonically. When a client switches from one server to
              another in a cluster, it can ensure that it never sees an
              older snapshot of data by avoiding servers that have index
              less than the largest value they have already observed.

              For a standalone or active-backup database, this is empty.

COLOPHON         top

       This page is part of the Open vSwitch (a distributed virtual
       multilayer switch) project.  Information about the project can be
       found at ⟨http://openvswitch.org/⟩.  If you have a bug report for
       this manual page, send it to bugs@openvswitch.org.  This page was
       obtained from the project's upstream Git repository
       ⟨https://github.com/openvswitch/ovs.git⟩ on 2020-09-18.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2020-09-16.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to man-pages@man7.org

Open vSwitch 2.14.90           DB Schema 1.1.0               ovsdb-server(5)

Pages that refer to this page: ovsdb-server(1)