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multipathd

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

Forground Mode. Don't daemonize, and print all messages to stdout and stderr.

-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.

-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 maps|multipaths

Show the multipath devices that the multipathd is monitoring.

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 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.

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 $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 $map

Stop monitoring a multipath device.

resize map|multipath $map

Resizes map $map to the given size

switch|switchgroup map $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.

fail path $path

Sets path $path into failed state.

reinstate path $path

Resumes path $path from failed state.

disablequeueing map|multipath $map

Disabled queuing on multipathed map $map

restorequeueing map|multipath $map

Restore queuing on multipahted map $map

SEE ALSO

multipath(8) kpartx(8) hotplug(8)

AUTHORS

multipathd was developed by Christophe Varoqui, <christophe.varoqui@free.fr> and others.