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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COLOPHON |
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ovsdb-client(1) Open vSwitch Manual ovsdb-client(1)
ovsdb-client - command-line interface to ovsdb-server(1)
Server-Level Commands:
ovsdb-client [options] list-dbs [server]
Database Schema Commands:
ovsdb-client [options] get-schema [server] [database]
ovsdb-client [options] list-tables [server] [database]
ovsdb-client [options] list-columns [server] [database]
[table]
Database Version Management Commands:
ovsdb-client [options] convert [server] schema
ovsdb-client [options] needs-conversion [server] schema
ovsdb-client [options] get-schema-version [server]
[database]
Data Management Commands:
ovsdb-client [options] transact [server] transaction
ovsdb-client [options] query [server] transaction
ovsdb-client [options] dump [server] [database] [table
[column...]]
ovsdb-client [options] backup [server] [database] >
snapshot
ovsdb-client [options] [--force] restore [server]
[database] < snapshot
ovsdb-client [options] monitor [server] [database] table
[column[,column]...]...
ovsdb-client [options] monitor [server] [database] ALL
ovsdb-client [options] monitor-cond [server] [database]
conditions table [column[,column]...]...
ovsdb-client [options] monitor-cond-since [server]
[database] [last-id] conditions table
[column[,column]...]...
ovsdb-client [options] wait [server] database state
Testing Commands:
ovsdb-client [options] lock [server] lock
ovsdb-client [options] steal [server] lock
ovsdb-client [options] unlock [server] lock
Other Commands:
ovsdb-client help
Cluster Options:
[--no-leader-only]
Output formatting options:
[--format=format] [--data=format] [--no-headings]
[--pretty] [--bare] [--timestamp]
Daemon options:
[--pidfile[=pidfile]] [--overwrite-pidfile] [--detach]
[--no-chdir] [--no-self-confinement]
Logging options:
[-v[module[:destination[:level]]]]...
[--verbose[=module[:destination[:level]]]]...
[--log-file[=file]]
Public key infrastructure options:
[--private-key=privkey.pem]
[--certificate=cert.pem]
[--ca-cert=cacert.pem]
[--bootstrap-ca-cert=cacert.pem]
SSL connection options:
[--ssl-protocols=protocols]
[--ssl-ciphers=ciphers]
Replay options:
[--record[=directory]] [--replay[=directory]]
Common options:
[-h | --help] [-V | --version]
The ovsdb-client program is a command-line client for interacting
with a running ovsdb-server process. Each command connects to
the specified OVSDB server, which may be an OVSDB active or
passive connection method, as described in ovsdb(7). The default
server is unix:/usr/local/var/run/openvswitch/db.sock and the
default database is Open_vSwitch.
ovsdb-client supports the method1,method2,...,methodN syntax
described in ovsdb(7) for connecting to a cluster. When this
syntax is used, ovsdb-client tries the cluster members in random
order until it finds the cluster leader. Specify the
--no-leader-only option to instead accept any server that is
connected to the cluster.
For an introduction to OVSDB and its implementation in Open
vSwitch, see ovsdb(7).
The following sections describe the commands that ovsdb-client
supports.
Server-Level Commands
Most ovsdb-client commands work with an individual database, but
these commands apply to an entire database server.
list-dbs [server]
Connects to server, retrieves the list of known databases,
and prints them one per line. These database names are
the ones that other commands may use for database.
Database Schema Commands
These commands obtain the schema from a database and print it or
part of it.
get-schema [server] [database]
Connects to server, retrieves the schema for database, and
prints it in JSON format.
list-tables [server] [database]
Connects to server, retrieves the schema for database, and
prints a table listing the name of each table within the
database.
list-columns [server] [database] table
Connects to server, retrieves the schema for database, and
prints a table listing the name and type of each column.
If table is specified, only columns in that table are
listed; otherwise, the tables include columns in all
tables.
Database Version Management Commands
An OVSDB schema has a schema version number, and an OVSDB
database embeds a particular version of an OVSDB schema. These
version numbers take the form x.y.z, e.g. 1.2.3. The OVSDB
implementation does not enforce a particular version numbering
scheme, but schemas managed within the Open vSwitch project use
the following approach. Whenever the database schema is changed
in a non-backward compatible way (e.g. deleting a column or a
table), x is incremented (and y and z are reset to 0). When the
database schema is changed in a backward compatible way (e.g.
adding a new column), y is incremented (and z is reset to 0).
When the database schema is changed cosmetically (e.g.
reindenting its syntax), z is incremented.
Some OVSDB databases and schemas, especially very old ones, do
not have a version number.
Schema version numbers and Open vSwitch version numbers are
independent.
These commands work with different versions of OVSDB schemas and
databases.
convert [server] schema
Reads an OVSDB schema in JSON format, as specified in the
OVSDB specification, from schema, then connects to server
and requests the server to convert the database whose name
is specified in schema to the schema also specified in
schema.
The conversion is atomic, consistent, isolated, and
durable. Following the schema change, the server notifies
clients that use the set_db_change_aware RPC introduced in
Open vSwitch 2.9 and cancels their outstanding
transactions and monitors. The server disconnects other
clients, enabling them to notice the change when they
reconnect.
This command can do simple ``upgrades'' and ``downgrades''
on a database's schema. The data in the database must be
valid when interpreted under schema, with only one
exception: data for tables and columns that do not exist
in schema are ignored. Columns that exist in schema but
not in the database are set to their default values. All
of schema's constraints apply in full.
Some uses of this command can cause unrecoverable data
loss. For example, converting a database from a schema
that has a given column or table to one that does not will
delete all data in that column or table. Back up critical
databases before converting them.
This command works with clustered and standalone
databases. Standalone databases may also be converted
(offline) with ovsdb-tool's convert command.
needs-conversion [server] schema
Reads the schema from schema, then connects to server and
requests the schema from the database whose name is
specified in schema. If the two schemas are the same,
prints no on stdout; if they differ, prints yes.
get-schema-version [server] [database]
Connects to server, retrieves the schema for database, and
prints its version number on stdout. If database was
created before schema versioning was introduced, then it
will not have a version number and this command will print
a blank line.
get-schema-cksum [server] [database]
Connects to server, retrieves the schema for database, and
prints its checksum on stdout. If database does not
include a checksum, prints a blank line.
Data Management Commands
These commands read or modify the data in a database.
transact [server] transaction
Connects to server, sends it the specified transaction,
which must be a JSON array appropriate for use as the
params to a JSON-RPC transact request, and prints the
received reply on stdout.
query [server] transaction
This commands acts like a read-only version of transact.
It connects to server, sends it the specified transaction,
which must be a JSON array appropriate for use as the
params to a JSON-RPC transact request, and prints the
received reply on stdout. To ensure that the transaction
does not modify the database, this command appends an
abort operation to the set of operations included in
transaction before sending it to the database, and then
removes the abort result from the reply (if it is
present).
dump [server] [database] [table [column...]]
Connects to server, retrieves all of the data in database,
and prints it on stdout as a series of tables. If table is
specified, only that table is retrieved. If at least one
column is specified, only those columns are retrieved.
backup [server] [database] > snapshot
Connects to server, retrieves a snapshot of the schema and
data in database, and prints it on stdout in the format
used for OVSDB standalone and active-backup databases.
This is an appropriate way to back up any remote database.
The database snapshot that it outputs is suitable to be
served up directly by ovsdb-server or used as the input to
ovsdb-client restore.
Another way to back up a standalone or active-backup
database is to copy its database file, e.g. with cp. This
is safe even if the database is in use.
The output does not include ephemeral columns, which by
design do not survive across restarts of ovsdb-server.
[--force] restore [server] [database] < snapshot
Reads snapshot, which must be a OVSDB standalone or
active-backup database (possibly but not necessarily
created by ovsdb-client backup). Then, connects to
server, verifies that database and snapshot have the same
schema, then deletes all of the data in database and
replaces it by snapshot. The replacement happens
atomically, in a single transaction.
UUIDs for rows in the restored database will differ from
those in snapshot, because the OVSDB protocol does not
allow clients to specify row UUIDs. Another way to
restore a standalone or active-backup database, which does
also restore row UUIDs, is to stop the server or servers,
replace the database file by the snapshot, then restart
the database. Either way, ephemeral columns are not
restored, since by design they do not survive across
restarts of ovsdb-server.
Normally restore exits with a failure if snapshot and the
server's database have different schemas. In such a case,
it is a good idea to convert the database to the new
schema before restoring, e.g. with ovsdb-client convert.
Use --force to proceed regardless of schema differences
even though the restore might fail with an error or
succeed with surprising results.
monitor [server] [database] table [column[,column]...]...
monitor-cond [server] [database] conditions table
[column[,column]...]...
monitor-cond-since [server] [database] [last-id] conditions table
[column[,column]...]...
Connects to server and monitors the contents of rows that
match conditions in table in database. By default, the
initial contents of table are printed, followed by each
change as it occurs. If conditions empty, all rows will
be monitored. If at least one column is specified, only
those columns are monitored. The following column names
have special meanings:
!initial
Do not print the initial contents of the specified
columns.
!insert
Do not print newly inserted rows.
!delete
Do not print deleted rows.
!modify
Do not print modifications to existing rows.
Multiple [column[,column]...] groups may be specified as
separate arguments, e.g. to apply different reporting
parameters to each group. Whether multiple groups or only
a single group is specified, any given column may only be
mentioned once on the command line.
conditions is a JSON array of <condition> as defined in
RFC 7047 5.1 with the following change: A condition can be
either a 3-element JSON array as described in the RFC or a
boolean value.
If --detach is used with monitor, monitor-cond or
monitor-cond-since, then ovsdb-client detaches after it
has successfully received and printed the initial contents
of table.
The monitor command uses RFC 7047 "monitor" method to open
a monitor session with the server. The monitor-cond and
monitor-cond-since commandls uses RFC 7047 extension
"monitor_cond" and "monitor_cond_since" methods. See
ovsdb-server(1) for details.
monitor [server] [database] ALL
Connects to server and monitors the contents of all tables
in database. Prints initial values and all kinds of
changes to all columns in the database. The --detach
option causes ovsdb-client to detach after it successfully
receives and prints the initial database contents.
The monitor command uses RFC 7047 "monitor" method to open
a monitor session with the server.
wait [server] database state
Waits for database on server to enter a desired state,
which may be one of:
added Waits until a database with the given name has been
added to server.
connected
Waits until a database with the given name has been
added to server. Then, if database is clustered,
additionally waits until it has joined and
connected to its cluster.
removed
Waits until database has been removed from the
database server. This can also be used to wait for
a database to complete leaving its cluster, because
ovsdb-server removes a database at that point.
database is mandatory for this command because it is often
used to check for databases that have not yet been added
to the server, so that the ovsdb-client semantics of
acting on a default database do not work.
This command acts on a particular database server, not on
a cluster, so server must name a single server, not a
comma-delimited list of servers.
Testing commands
These commands are mostly of interest for testing the correctness
of the OVSDB server.
lock [server] lock
steal [server] lock
unlock [server] lock
Connects to server and issues corresponding RFC 7047 lock
operations on lock. Prints json reply or subsequent update
messages. The --detach option causes ovsdb-client to
detach after it successfully receives and prints the
initial reply.
When running with the --detach option, lock, steal, unlock
and exit commands can be issued by using ovs-appctl. exit
command causes the ovsdb-client to close its ovsdb-server
connection before exit. The lock, steal and unlock
commands can be used to issue additional lock operations
over the same ovsdb-server connection. All above commands
take a single lock argument, which does not have to be the
same as the lock that ovsdb-client started with.
Output Formatting Options
Much of the output from ovsdb-client is in the form of tables.
The following options controlling output formatting:
-f format
--format=format
Sets the type of table formatting. The following types of
format are available:
table (default)
2-D text tables with aligned columns.
list A list with one column per line and rows separated
by a blank line.
html HTML tables.
csv Comma-separated values as defined in RFC 4180.
json JSON format as defined in RFC 4627. The output is
a sequence of JSON objects, each of which
corresponds to one table. Each JSON object has the
following members with the noted values:
caption
The table's caption. This member is omitted
if the table has no caption.
headings
An array with one element per table column.
Each array element is a string giving the
corresponding column's heading.
data An array with one element per table row.
Each element is also an array with one
element per table column. The elements of
this second-level array are the cells that
constitute the table. Cells that represent
OVSDB data or data types are expressed in
the format described in the OVSDB
specification; other cells are simply
expressed as text strings.
-d format
--data=format
Sets the formatting for cells within output tables unless
the table format is set to json, in which case json
formatting is always used when formatting cells. The
following types of format are available:
string (default)
The simple format described in the Database Values
section of ovs-vsctl(8).
bare The simple format with punctuation stripped off: []
and {} are omitted around sets, maps, and empty
columns, items within sets and maps are space-
separated, and strings are never quoted. This
format may be easier for scripts to parse.
json The RFC 4627 JSON format as described above.
--no-headings
This option suppresses the heading row that otherwise
appears in the first row of table output.
--pretty
By default, JSON in output is printed as compactly as
possible. This option causes JSON in output to be printed
in a more readable fashion. Members of objects and
elements of arrays are printed one per line, with
indentation.
This option does not affect JSON in tables, which is
always printed compactly.
--bare Equivalent to --format=list --data=bare --no-headings.
--max-column-width=n
For table output only, limits the width of any column in
the output to n columns. Longer cell data is truncated to
fit, as necessary. Columns are always wide enough to
display the column names, if the heading row is printed.
--timestamp
For the monitor, monitor-cond and monitor-cond-since
commands, add a timestamp to each table update. Most
output formats add the timestamp on a line of its own just
above the table. The JSON output format puts the
timestamp in a member of the top-level JSON object named
time.
-t
--timeout=secs
Limits ovsdb-client runtime to approximately secs seconds.
If the timeout expires, ovsdb-client will exit with a
SIGALRM signal.
Daemon Options
The daemon options apply only to the monitor, monitor-cond and
monitor-cond-since commands. With any other command, they have
no effect.
The following options are valid on POSIX based platforms.
--pidfile[=pidfile]
Causes a file (by default, ovsdb-client.pid) to be created
indicating the PID of the running process. If the pidfile
argument is not specified, or if it does not begin with /,
then it is created in /usr/local/var/run/openvswitch.
If --pidfile is not specified, no pidfile is created.
--overwrite-pidfile
By default, when --pidfile is specified and the specified
pidfile already exists and is locked by a running process,
ovsdb-client refuses to start. Specify
--overwrite-pidfile to cause it to instead overwrite the
pidfile.
When --pidfile is not specified, this option has no
effect.
--detach
Runs ovsdb-client as a background process. The process
forks, and in the child it starts a new session, closes
the standard file descriptors (which has the side effect
of disabling logging to the console), and changes its
current directory to the root (unless --no-chdir is
specified). After the child completes its initialization,
the parent exits.
--monitor
Creates an additional process to monitor the ovsdb-client
daemon. If the daemon dies due to a signal that indicates
a programming error (SIGABRT, SIGALRM, SIGBUS, SIGFPE,
SIGILL, SIGPIPE, SIGSEGV, SIGXCPU, or SIGXFSZ) then the
monitor process starts a new copy of it. If the daemon
dies or exits for another reason, the monitor process
exits.
This option is normally used with --detach, but it also
functions without it.
--no-chdir
By default, when --detach is specified, ovsdb-client
changes its current working directory to the root
directory after it detaches. Otherwise, invoking
ovsdb-client from a carelessly chosen directory would
prevent the administrator from unmounting the file system
that holds that directory.
Specifying --no-chdir suppresses this behavior, preventing
ovsdb-client from changing its current working directory.
This may be useful for collecting core files, since it is
common behavior to write core dumps into the current
working directory and the root directory is not a good
directory to use.
This option has no effect when --detach is not specified.
--no-self-confinement
By default daemon will try to self-confine itself to work
with files under well-known directories determined during
build. It is better to stick with this default behavior
and not to use this flag unless some other Access Control
is used to confine daemon. Note that in contrast to other
access control implementations that are typically enforced
from kernel-space (e.g. DAC or MAC), self-confinement is
imposed from the user-space daemon itself and hence should
not be considered as a full confinement strategy, but
instead should be viewed as an additional layer of
security.
--user Causes ovsdb-client to run as a different user specified
in "user:group", thus dropping most of the root
privileges. Short forms "user" and ":group" are also
allowed, with current user or group are assumed
respectively. Only daemons started by the root user
accepts this argument.
On Linux, daemons will be granted CAP_IPC_LOCK and
CAP_NET_BIND_SERVICES before dropping root privileges.
Daemons that interact with a datapath, such as
ovs-vswitchd, will be granted three additional
capabilities, namely CAP_NET_ADMIN, CAP_NET_BROADCAST and
CAP_NET_RAW. The capability change will apply even if the
new user is root.
On Windows, this option is not currently supported. For
security reasons, specifying this option will cause the
daemon process not to start.
Logging Options
-v[spec]
--verbose=[spec]
Sets logging levels. Without any spec, sets the log level
for every module and destination to dbg. Otherwise, spec
is a list of words separated by spaces or commas or
colons, up to one from each category below:
• A valid module name, as displayed by the vlog/list
command on ovs-appctl(8), limits the log level
change to the specified module.
• syslog, console, or file, to limit the log level
change to only to the system log, to the console,
or to a file, respectively. (If --detach is
specified, ovsdb-client closes its standard file
descriptors, so logging to the console will have no
effect.)
On Windows platform, syslog is accepted as a word
and is only useful along with the --syslog-target
option (the word has no effect otherwise).
• off, emer, err, warn, info, or dbg, to control the
log level. Messages of the given severity or
higher will be logged, and messages of lower
severity will be filtered out. off filters out all
messages. See ovs-appctl(8) for a definition of
each log level.
Case is not significant within spec.
Regardless of the log levels set for file, logging to a
file will not take place unless --log-file is also
specified (see below).
For compatibility with older versions of OVS, any is
accepted as a word but has no effect.
-v
--verbose
Sets the maximum logging verbosity level, equivalent to
--verbose=dbg.
-vPATTERN:destination:pattern
--verbose=PATTERN:destination:pattern
Sets the log pattern for destination to pattern. Refer to
ovs-appctl(8) for a description of the valid syntax for
pattern.
-vFACILITY:facility
--verbose=FACILITY:facility
Sets the RFC5424 facility of the log message. facility can
be one of kern, user, mail, daemon, auth, syslog, lpr,
news, uucp, clock, ftp, ntp, audit, alert, clock2, local0,
local1, local2, local3, local4, local5, local6 or local7.
If this option is not specified, daemon is used as the
default for the local system syslog and local0 is used
while sending a message to the target provided via the
--syslog-target option.
--log-file[=file]
Enables logging to a file. If file is specified, then it
is used as the exact name for the log file. The default
log file name used if file is omitted is
/usr/local/var/log/openvswitch/ovsdb-client.log.
--syslog-target=host:port
Send syslog messages to UDP port on host, in addition to
the system syslog. The host must be a numerical IP
address, not a hostname.
--syslog-method=method
Specify method how syslog messages should be sent to
syslog daemon. Following forms are supported:
• libc, use libc syslog() function. Downside of
using this options is that libc adds fixed prefix
to every message before it is actually sent to the
syslog daemon over /dev/log UNIX domain socket.
• unix:file, use UNIX domain socket directly. It is
possible to specify arbitrary message format with
this option. However, rsyslogd 8.9 and older
versions use hard coded parser function anyway that
limits UNIX domain socket use. If you want to use
arbitrary message format with older rsyslogd
versions, then use UDP socket to localhost IP
address instead.
• udp:ip:port, use UDP socket. With this method it
is possible to use arbitrary message format also
with older rsyslogd. When sending syslog messages
over UDP socket extra precaution needs to be taken
into account, for example, syslog daemon needs to
be configured to listen on the specified UDP port,
accidental iptables rules could be interfering with
local syslog traffic and there are some security
considerations that apply to UDP sockets, but do
not apply to UNIX domain sockets.
• null, discards all messages logged to syslog.
The default is taken from the OVS_SYSLOG_METHOD
environment variable; if it is unset, the default is libc.
Public Key Infrastructure Options
-p privkey.pem
--private-key=privkey.pem
Specifies a PEM file containing the private key used as
ovsdb-client's identity for outgoing SSL connections.
-c cert.pem
--certificate=cert.pem
Specifies a PEM file containing a certificate that
certifies the private key specified on -p or --private-key
to be trustworthy. The certificate must be signed by the
certificate authority (CA) that the peer in SSL
connections will use to verify it.
-C cacert.pem
--ca-cert=cacert.pem
Specifies a PEM file containing the CA certificate that
ovsdb-client should use to verify certificates presented
to it by SSL peers. (This may be the same certificate
that SSL peers use to verify the certificate specified on
-c or --certificate, or it may be a different one,
depending on the PKI design in use.)
-C none
--ca-cert=none
Disables verification of certificates presented by SSL
peers. This introduces a security risk, because it means
that certificates cannot be verified to be those of known
trusted hosts.
--bootstrap-ca-cert=cacert.pem
When cacert.pem exists, this option has the same effect as
-C or --ca-cert. If it does not exist, then ovsdb-client
will attempt to obtain the CA certificate from the SSL
peer on its first SSL connection and save it to the named
PEM file. If it is successful, it will immediately drop
the connection and reconnect, and from then on all SSL
connections must be authenticated by a certificate signed
by the CA certificate thus obtained.
This option exposes the SSL connection to a man-in-the-
middle attack obtaining the initial CA certificate, but it
may be useful for bootstrapping.
This option is only useful if the SSL peer sends its CA
certificate as part of the SSL certificate chain. The SSL
protocol does not require the server to send the CA
certificate.
This option is mutually exclusive with -C and --ca-cert.
SSL Connection Options
--ssl-protocols=protocols
Specifies, in a comma- or space-delimited list, the SSL
protocols ovsdb-client will enable for SSL connections.
Supported protocols include TLSv1, TLSv1.1, and TLSv1.2.
Regardless of order, the highest protocol supported by
both sides will be chosen when making the connection. The
default when this option is omitted is
TLSv1,TLSv1.1,TLSv1.2.
--ssl-ciphers=ciphers
Specifies, in OpenSSL cipher string format, the ciphers
ovsdb-client will support for SSL connections. The
default when this option is omitted is HIGH:!aNULL:!MD5.
Other Options
--record[=directory]
Sets the process in "recording" mode, in which it will
record all the connections, data from streams (Unix domain
and network sockets) and some other important necessary
bits, so they could be replayed later. Recorded data is
stored in replay files in specified directory. If
directory does not begin with /, it is interpreted as
relative to /usr/local/var/run/openvswitch. If directory
is not specified, /usr/local/var/run/openvswitch will be
used.
--replay[=directory]
Sets the process in "replay" mode, in which it will read
information about connections, data from streams (Unix
domain and network sockets) and some other necessary bits
directly from replay files instead of using real sockets.
Replay files from the directory will be used. If
directory does not begin with /, it is interpreted as
relative to /usr/local/var/run/openvswitch. If directory
is not specified, /usr/local/var/run/openvswitch will be
used.
-h
--help Prints a brief help message to the console.
-V
--version
Prints version information to the console.
ovsdb(7), ovsdb-server(1), ovsdb-client(1).
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 [email protected]. This page was
obtained from the project's upstream Git repository
⟨https://github.com/openvswitch/ovs.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-07.) 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
[email protected]
Open vSwitch 3.2.90 ovsdb-client(1)
Pages that refer to this page: ovsdb-client(1), ovsdb-server(1), ovsdb-tool(1), ovsdb(7)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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