-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:

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 @LOGDIR@/program.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 as how syslog messages should be sent to syslog daemon. The following forms are supported: