NAME¶
multipath - Device mapper target autoconfig
SYNOPSIS¶
multipath [
-v verbosity] [
-d]
[
-h|
-l|
-ll|
-f|
-t|
-F-B]
[
-p failover|
multibus|
group_by_serial|
group_by_prio|
group_by_node_name]
[
device]
DESCRIPTION¶
multipath 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
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
- -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 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 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.