NAME

       multipathd - multipath daemon

SYNOPSIS

       multipathd [options]

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 config 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.

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,     e.g.
              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 any 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

       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

       multipathd was developed by Christophe Varoqui, <christophe.varoqui@opensvc.com> and others.