bionic (8) multipathd.8.gz

Provided by: multipath-tools_0.7.4-2ubuntu3.2_amd64 bug

NAME

       multipathd - Multipath daemon.

SYNOPSIS

       multipathd [-d|-k] [-s] [-v verbosity] [-B] [-n]

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     Ignore  new  devices. multipathd will not create a multipath device unless the WWID for the device
              is already listed in the WWIDs file.

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 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.

SEE ALSO

       multipath(8), kpartx(8), sd_notify(3), system.service(5).

AUTHORS

       multipath-tools was developed by Christophe Varoqui <christophe.varoqui@opensvc.com> and others.