MULTIPATH(8) Linux Administrator's Manual MULTIPATH(8)NAMEmultipath - Device mapper target autoconfig
SYNOPSISmultipath [-v verbosity] [-b bindings_file] [-d]
[-h|-l|-ll|-f|-t|-F|-B|-c|-q|-r|-a|-A|-w|-W] [-p failover|multi‐
bus|group_by_serial|group_by_prio|group_by_node_name] [device]
DESCRIPTIONmultipath is used to detect multiple paths to devices for fail-over or
performance reasons and coalesces them
OPTIONS-v level
verbosity, print all paths and multipaths
0 no output
1 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
-h print usage text
-d dry run, do not create or update devmaps
-l show the current multipath topology from information fetched in
sysfs and the device mapper
-ll show the current multipath topology from all available informa‐
tion (sysfs, the device mapper, path checkers ...)
-f flush a multipath device map specified as parameter, if unused
-F flush all unused multipath device maps
-t print internal hardware table to stdout
-r force devmap reload
-B treat the bindings file as read only
-b bindings_file
set user_friendly_names bindings file location. The default is
/etc/multipath/bindings
-c check if a block device should be a path in a multipath device
-q allow device tables with queue_if_no_path when multipathd is not
running
-a add the wwid for the specified device to the wwids file
-A add wwids from any kernel command line mpath.wwid parameters to
the wwids file
-w remove the wwid for the specified device from the wwids file
-W reset the wwids file to only include the current multipath
devices
-p policy
force new maps to use the specified policy:
failover 1 path per priority group
multibus all paths in 1 priority group
group_by_serial
1 priority group per serial
group_by_prio
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
group_by_node_name
1 priority group per target node name. Target
node names are fetched in /sys/class/fc_trans‐
port/target*/node_name.
Existing maps are not modified.
device 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
SEE ALSOmultipathd(8), multipath.conf(5), kpartx(8), udev(8), dmsetup(8) hot‐
plug(8)AUTHORSmultipath was developed by Christophe Varoqui, <christophe.varo‐
qui@opensvc.com> and others.
July 2006 MULTIPATH(8)