fence_mpath (8) - Linux Manuals

fence_mpath: Fence agent for multipath persistent reservation

Command to display fence_mpath manual in Linux: $ man 8 fence_mpath

NAME

fence_mpath - Fence agent for multipath persistent reservation

DESCRIPTION

fence_mpath is an I/O fencing agent that uses SCSI-3 persistent reservations to control access multipath devices. Underlying devices must support SCSI-3 persistent reservations (SPC-3 or greater) as well as the "preempt-and-abort" subcommand. The fence_mpath agent works by having a unique key for each node that has to be set in /etc/multipath.conf. Once registered, a single node will become the reservation holder by creating a "write exclusive, registrants only" reservation on the device(s). The result is that only registered nodes may write to the device(s). When a node failure occurs, the fence_mpath agent will remove the key belonging to the failed node from the device(s). The failed node will no longer be able to write to the device(s). A manual reboot is required.

fence_mpath accepts options on the command line as well as from stdin. Fenced sends parameters through stdin when it execs the agent. fence_mpath can be run by itself with command line options. This is useful for testing and for turning outlets on or off from scripts.

Vendor URL: https://www.sourceware.org/dm/

PARAMETERS

-o, --action=[action]: Fencing Action (Default Value: off)
-k, --key=[key]: Key to use for the current operation. This key should be unique to a node and have to be written in /etc/multipath.conf. For the "on" action, the key specifies the key use to register the local node. For the "off" action, this key specifies the key to be removed from the device(s). This parameter is always required.
-d, --devices=[devices]: List of devices to use for current operation. Devices can be comma-separated list of device-mapper multipath devices (eg. /dev/mapper/3600508b400105df70000e00000ac0000 or /dev/mapper/mpath1). Each device must support SCSI-3 persistent reservations.
-v, --verbose: Verbose mode
-D, --debug-file=[debugfile]: Write debug information to given file
-V, --version: Display version information and exit
-h, --help: Display help and exit
--power-wait=[seconds]: Wait X seconds after issuing ON/OFF (Default Value: 0)
--login-timeout=[seconds]: Wait X seconds for cmd prompt after login (Default Value: 5)
--power-timeout=[seconds]: Test X seconds for status change after ON/OFF (Default Value: 20)
--delay=[seconds]: Wait X seconds before fencing is started (Default Value: 0)
--mpathpersist-path=[path]: Path to mpathpersist binary (Default Value: /usr/sbin/mpathpersist)
--shell-timeout=[seconds]: Wait X seconds for cmd prompt after issuing command (Default Value: 3)
--store-path=[path]: Path to directory where fence agent can store information (Default Value: /var/run/cluster)
--retry-on=[attempts]: Count of attempts to retry power on (Default Value: 1)
--use-sudo: Use sudo (without password) when calling 3rd party sotfware.

ACTIONS

on: Power on machine.
off: Power off machine.
status: This returns the status of the plug/virtual machine.
list: List available plugs with aliases/virtual machines if there is support for more then one device. Returns N/A otherwise.
list-status: List available plugs with aliases/virtual machines and their power state if it can be obtained without additional commands.
monitor: Check the health of fence device
metadata: Display the XML metadata describing this resource.

STDIN PARAMETERS

action: Fencing Action (Default Value: off)
key: Key to use for the current operation. This key should be unique to a node and have to be written in /etc/multipath.conf. For the "on" action, the key specifies the key use to register the local node. For the "off" action, this key specifies the key to be removed from the device(s). This parameter is always required.
devices: List of devices to use for current operation. Devices can be comma-separated list of device-mapper multipath devices (eg. /dev/mapper/3600508b400105df70000e00000ac0000 or /dev/mapper/mpath1). Each device must support SCSI-3 persistent reservations.
verbose: Verbose mode
debug: Write debug information to given file
version: Display version information and exit
help: Display help and exit
power_wait: Wait X seconds after issuing ON/OFF (Default Value: 0)
login_timeout: Wait X seconds for cmd prompt after login (Default Value: 5)
power_timeout: Test X seconds for status change after ON/OFF (Default Value: 20)
delay: Wait X seconds before fencing is started (Default Value: 0)
mpathpersist_path: Path to mpathpersist binary (Default Value: /usr/sbin/mpathpersist)
shell_timeout: Wait X seconds for cmd prompt after issuing command (Default Value: 3)
store_path: Path to directory where fence agent can store information (Default Value: /var/run/cluster)
retry_on: Count of attempts to retry power on (Default Value: 1)
sudo: Use sudo (without password) when calling 3rd party sotfware.