multipathd - Multipath daemon.
multipathd [
-d] [
-s] [
-v verbosity]
[
-B] [
-w]
multipathd [
-v verbosity]
-kcommand
multipathd [
-v verbosity]
-k
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.
With the
-k option,
multipathd acts as a client utility that sends
commands to a running instance of the multipathd daemon (see
COMMANDS
below).
- -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.
- -kcommand
- multipathd executes the given command (see COMMANDS
below). If the command contains whitespace or shell special characters, it
needs to be quoted like in multipathd -k'show topology'. No
whitespace is allowed between the -k and the command string.
- -k
- multipathd executes the multipathc interactive shell
for entering commands (see COMMANDS below).
- -n
-
IGNORED. Use the option find_multipaths to
control the treatment of newly detected devices by multipathd. See
multipath.conf(5).
- -w
- Since kernel 4.14 a new device-mapper event polling
interface is used for updating multipath devices on dmevents. Use this
flag to force it to use the old event waiting method, based on creating a
separate thread for each device.
- 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
- Rereads the configuration, and reloads all changed
multipath devices. This also happens at startup, when the service is
reload, or when a SIGHUP is received.
- reconfigure all
- Rereads the configuration, and reloads all multipath
devices regardless of whether or not they have changed. This also happens
when multipath -r is run.
- 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 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.
- path $path setmarginal
- move $path to a marginal pathgroup. The path will remain in
the marginal path group until unsetmarginal is called. This command
will only work if marginal_pathgroups is enabled and there is no
Shaky paths detection method configured (see the multipath.conf man page
for details).
- path $path unsetmarginal
- return marginal path $path to its normal pathgroup. This
command will only work if marginal_pathgroups is enabled and there
is no Shaky paths detection method configured (see the multipath.conf man
page for details).
- map $map unsetmarginal
- return all marginal paths in $map to their normal
pathgroups. This command will only work if marginal_pathgroups is
enabled and there is no Shaky paths detection method configured (see the
multipath.conf man page for details).
- quit|exit
- End interactive session.
- shutdown
- Stop multipathd.
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.
multipathc(8),
multipath(8),
kpartx(8) sd_notify(3),
systemd.service(5).
multipath-tools was developed by Christophe Varoqui
<
[email protected]> and others.