Provided by: multipath-tools_0.7.4-2ubuntu3.2_amd64
NAME
multipath - Device mapper target autoconfig.
SYNOPSIS
multipath [-v verbosity] [-b bindings_file] [-d] [-h|-l|-ll|-f|-t|-F|-B|-c|-C|-q|-r|-i|-a|-u|-U|-w|-W] [-p failover|multibus|group_by_serial|group_by_prio|group_by_node_name] [-R retries] [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 Display the currently used multipathd configuration. -r Force devmap reload. -i Ignore WWIDs file when processing devices. -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. -C Check if a multipath device has usable paths. This can be used to test whether or not I/O on this device is likely to succeed. The command itself doesn't attempt to do I/O on the 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. -u Check if the device specified in the program environment should be a path in a multipath device. -U Check if the device specified in the program environment is a multipath device with usable paths. See -C. -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 One path per priority group. multibus All paths in one priority group. group_by_serial One priority group per serial number. group_by_prio One 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 One priority group per target node name. Target node names are fetched in /sys/class/fc_transport/target*/node_name. Existing maps are not modified. -R retries Number of times to retry flushing multipath devices that are in-use. The default is 0. 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: • /dev/sdX • major:minor
SEE ALSO
multipathd(8), multipath.conf(5), kpartx(8), udev(8), dmsetup(8), hotplug(8).
AUTHORS
multipath-tools was developed by Christophe Varoqui <christophe.varoqui@opensvc.com> and others.