multipath (8) - Linux Manuals

multipath: Device mapper target autoconfig


multipath - Device mapper target autoconfig


multipath [-v verbosity] [-b bindings_file] [-d] [-h|-l|-ll|-f|-t|-F|-B|-c|-q|-r|-r|-a|-A|-w|] [-p failover|multibus|group_by_serial|group_by_prio|group_by_node_name] [device]


multipath is used to detect multiple paths to devices for fail-over or performance reasons and coalesces them


-v level
verbosity, print all paths and multipaths
no output
print the created or updated multipath names only, for use to feed other tools like kpartx
2 +
print all info : detected paths, coalesced paths (ie multipaths) and device maps
print usage text
dry run, do not create or update devmaps
show the current multipath topology from information fetched in sysfs and the device mapper
show the current multipath topology from all available information (sysfs, the device mapper, path checkers ...)
flush a multipath device map specified as parameter, if unused
flush all unused multipath device maps
print internal hardware table to stdout
force devmap reload
ignore wwids file when processing devices
treat the bindings file as read only
-b bindings_file
set user_friendly_names bindings file location. The default is /etc/multipath/bindings
check if a block device should be a path in a multipath device
allow device tables with queue_if_no_path when multipathd is not running
add the wwid for the specified device to the wwids file
add wwids from any kernel command line mpath.wwid parameters to the wwids file
remove the wwid for the specified device from the wwids file
reset the wwids file to only include the current multipath devices
-T tm:valid
check if tm matches the multipathd configuration timestamp value from /run/multipathd/timestamp If so, return success if valid is 1. Otherwise, return failure. If the timestamp doesn't match continue with multipath execution. This option is designed to be used with -c by the udev rules.
-p policy
force new maps to use the specified policy:
1 path per priority group
all paths in 1 priority group
1 priority group per serial
1 priority group per priority value. Priorities are determined by callout programs specified as a global, per-controller or per-multipath option in the configuration file
1 priority group per target node name. Target node names are fetched in /sys/class/fc_transport/target*/node_name.
Existing maps are not modified.
update only the devmap the path pointed by device is in. device is in the /dev/sdb (as shown by udev in the $DEVNAME variable) or major:minor format. device may alternatively be a multipath mapname


multipath was developed by Christophe Varoqui, <christophe.varoqui [at]> and others.


multipathd(8), multipath.conf(5), kpartx(8), udev(8), dmsetup(8) hotplug(8)