NAME¶
multipathd - Multipath daemon.
SYNOPSIS¶
multipathd [-d|-k] [-s]
[-v verbosity] [-B]
DESCRIPTION¶
The multipathd daemon is in charge of checking for failed paths. When
this happens, it will reconfigure the multipath map the path belongs to, so
that this map regains its maximum performance and redundancy.
This daemon executes the external multipath tool when
events occur. In turn, the multipath tool signals the multipathd daemon when
it is done with devmap reconfiguration, so that it can refresh its failed
path list.
OPTIONS¶
- -d
- Foreground Mode. Don't daemonize, and print all messages to stdout and
stderr.
- -s
- Suppress timestamps. Do not prefix logging messages with a timestamp.
- -v level
- Verbosity level. Print additional information while running multipathd. A
level of 0 means only print errors. A level of 3 or greater prints
debugging information as well.
- -B
- Read-only bindings file. multipathd will not write to the
user_friendly_names bindings file. If a user_friendly_name
doesn't already exist for a device, it will use its WWID as its
alias.
- -k
- multipathd will enter interactive mode. From this mode, the available
commands can be viewed by entering 'help'. When you are finished
entering commands, press CTRL-D to quit.
- -n
- IGNORED. Use the option find_multipaths to control the
treatment of newly detected devices by multipathd. See
multipath.conf(5).
COMMANDS¶
- The following commands can be used in interactive mode:
- list|show paths
- Show the paths that multipathd is monitoring, and their state.
- list|show paths format $format
- Show the paths that multipathd is monitoring, using a format string with
path format wildcards.
- list|show maps|multipaths
- Show the multipath devices that the multipathd is monitoring.
- list|show maps|multipaths format $format
- Show the status of all multipath devices that the multipathd is
monitoring, using a format string with multipath format wildcards.
- list|show maps|multipaths status
- Show the status of all multipath devices that the multipathd is
monitoring.
- list|show maps|multipaths stats
- Show some statistics of all multipath devices that the multipathd is
monitoring.
- list|show maps|multipaths topology
- Show the current multipath topology. Same as 'multipath -ll'.
- list|show topology
- Show the current multipath topology. Same as 'multipath -ll'.
- list|show map|multipath $map topology
- Show topology of a single multipath device specified by $map, for example
36005076303ffc56200000000000010aa. This map could be obtained from
'list maps'.
- list|show wildcards
- Show the format wildcards used in interactive commands taking
$format.
- list|show config
- Show the currently used configuration, derived from default values and
values specified within the configuration file
/etc/multipath.conf.
- list|show config local
- Show the currently used configuration like show config, but
limiting the devices section to those devices that are actually present in
the system.
- list|show blacklist
- Show the currently used blacklist rules, derived from default values and
values specified within the configuration file
/etc/multipath.conf.
- list|show devices
- Show all available block devices by name including the information if they
are blacklisted or not.
- list|show status
- Show the number of path checkers in each possible state, the number of
monitored paths, and whether multipathd is currently handling a
uevent.
- list|show daemon
- Show the current state of the multipathd daemon.
- add path $path
- Add a path to the list of monitored paths. $path is as listed in
/sys/block (e.g. sda).
- remove|del path $path
- Stop monitoring a path. $path is as listed in /sys/block (e.g. sda).
- add map|multipath $map
- Add a multipath device to the list of monitored devices. $map can either
be a device-mapper device as listed in /sys/block (e.g. dm-0) or it can be
the alias for the multipath device (e.g. mpath1) or the uid of the
multipath device (e.g. 36005076303ffc56200000000000010aa).
- remove|del map|multipath $map
- Stop monitoring a multipath device.
- resize map|multipath $map
- Resizes map $map to the given size.
- switch|switchgroup map|multipath $map group $group
- Force a multipath device to switch to a specific path group. $group is the
path group index, starting with 1.
- reconfigure
- Reconfigures the multipaths. This should be triggered automatically after
anyi hotplug event.
- suspend map|multipath $map
- Sets map $map into suspend state.
- resume map|multipath $map
- Resumes map $map from suspend state.
- reset map|multipath $map
- Reassign existing device-mapper table(s) use use the multipath device,
instead of its path devices.
- reload map|multipath $map
- Reload a multipath device.
- fail path $path
- Sets path $path into failed state.
- reinstate path $path
- Resumes path $path from failed state.
- disablequeueing maps|multipaths
- Disable queueing on all multipath devices.
- restorequeueing maps|multipaths
- Restore queueing on all multipath devices.
- disablequeueing map|multipath $map
- Disable queuing on multipathed map $map.
- restorequeueing map|multipath $map
- Restore queuing on multipahted map $map.
- forcequeueing daemon
- Forces multipathd into queue_without_daemon mode, so that no_path_retry
queueing will not be disabled when the daemon stops.
- restorequeueing daemon
- Restores configured queue_without_daemon mode.
- map|multipath $map setprstatus
- Enable persistent reservation management on $map.
- map|multipath $map unsetprstatus
- Disable persistent reservation management on $map.
- map|multipath $map getprstatus
- Get the current persistent reservation management status of $map.
- map|multipath $map getprkey
- Get the current persistent reservation key associated with $map.
- map|multipath $map setprkey key $key
- Set the persistent reservation key associated with $map to $key in the
prkeys_file. This key will only be used by multipathd if
reservation_key is set to file in
/etc/multipath.conf.
- map|multipath $map unsetprkey
- Remove the persistent reservation key associated with $map from the
prkeys_file. This will only unset the key used by multipathd if
reservation_key is set to file in
/etc/multipath.conf.
- quit|exit
- End interactive session.
- shutdown
- Stop multipathd.
SYSTEMD INTEGRATION¶
When compiled with systemd support two systemd service files are installed,
multipathd.service and multipathd.socket The
multipathd.socket service instructs systemd to intercept the CLI
command socket, so that any call to the CLI interface will start-up the daemon
if required. The multipathd.service file carries the definitions for
controlling the multipath daemon. The daemon itself uses the
sd_notify(3) interface to communicate with systemd. The following unit
keywords are recognized:
- WatchdogSec=
- Enables the internal watchdog from systemd. multipath will send a
notification via sd_notify(3) to systemd to reset the watchdog. If
specified the polling_interval and max_polling_interval
settings will be overridden by the watchdog settings. Please note that
systemd prior to version 207 has issues which prevent the systemd-provided
watchdog from working correctly. So the watchdog is not enabled per
default, but has to be enabled manually by updating the
multipathd.service file.
- OOMScoreAdjust=
- Overrides the internal OOM adjust mechanism.
- LimitNOFILE=
- Overrides the max_fds configuration setting.
AUTHORS¶
multipath-tools was developed by Christophe Varoqui
<christophe.varoqui@opensvc.com> and others.
