NAME¶
multipath - Device mapper target autoconfig
SYNOPSIS¶
multipath [
-v verbosity]
[
-b bindings_file] [
-d]
[
-h|
-l|
-ll|
-f|
-t|
-F|
-B|
-c|
-q|
-r|
-w|
-W]
[
-p failover|
multibus|
group_by_serial|
group_by_prio|
group_by_node_name]
[
device]
DESCRIPTION¶
multipath is used to detect and coalesce multiple paths to devices, for
fail-over or performance reasons.
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 information (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
- -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_transport/target*/node_name.
Existing maps are not modified.
- device
- update only the devmap specified by device, which is either:
- •
- a devmap name
- •
- a path associated with the desired devmap; the path may be in one of the
following formats:
SEE ALSO¶
multipathd(8),
multipath.conf(5),
kpartx(8),
udev(8),
dmsetup(8) hotplug(8)
AUTHORS¶
multipath was developed by Christophe Varoqui,
<christophe.varoqui@opensvc.com> and others.
