multipathd Linux Service

multipathd service:

Multipath daemon. It checks for failed paths and monitors them.
Now lets see the manual of multipathd service.
Manual multipathd:
NAME
multipathd - multipath daemon
SYNOPSYS
multipathd [options]
DESCRIPTION
The multipathd daemon is in charge of checking for failed paths. and monitoring them to see when they have recov- ered. When a failed path has recovered or a new path has come online, multipathd switches to the optimal path group, to ensure maximum performace.
OPTIONS
-d Forground Mode. Don't daemonize, and print all messages to stdout and stderr.
-v level
verbosity. 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 [options]
Issue a multipathd command. If no command is specified, you will enter interactive mode. From this mode, the available commands can be viewed by pressing the enter key. When you are finished entering commands, press CTRL-D to quit.
COMMANDS
list|show paths
Show the paths that multipathd is monitoring, and their state.
list|show maps
Show the multipath devices that the multipathd is monitoring.
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.
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).
remove|del map $map
Stop monitoring a multipath device.
switch|switchgroup map $map group $group
Force a multipath device to switch to a specific path group. is the path group index, starting with 1.
SEE ALSO
multipath(8) kpartx(8) hotplug(8)
AUTHORS
This man page was assembled by Patrick Caulfield for the Debian project. From documentation provided by the multi- path author Christophe Varoqui, <christophe.varoqui@free.fr> and others.