fencevsd Command

Purpose

Prevents an application running on a node or group of nodes from accessing a virtual shared disk or group of virtual shared disks.

Syntax

fencevsd {-a | -v vsd_name_list} -n node_list

Description

Under some circumstances, the system may believe a node has stopped functioning and begin recovery procedures, when the node is actually operational, but cut off from communication with other nodes running the same application. In this case, the problem node must not be allowed to serve requests for the virtual shared disks it normally serves until recovery is complete and the other nodes running the application recognize the problem node as operational. The fencevsd command prevents the problem node from filling requests for its virtual shared disks.

This command can be run from any node in the RSCT peer domain where the recoverable virtual shared disk subsystem is running.

Flags

-a: Specifies all virtual shared disks.
-v vsd_name_list: Specifies one or more virtual shared disk names, separated by commas.
-n node_list: Specifies one or more node numbers, separated by commas.

Parameters

logical_volume_name: Is the name of the logical volume you want to specify as a virtual shared disk. This logical volume must reside on the global volume group indicated. The length of the name must be less than or equal to 15 characters.
global_group_name: Is the name of the globally-accessible volume group previously defined by the vsdvg command where you want to specify a virtual shared disk. The length of the name must be less than or equal to 31 characters.
vsd_name: Specifies a unique name for the new virtual shared disk. This name must be unique within the RSCT peer domain, and, in order to avoid possible future naming conflicts, should also be unique across the overall cluster. The suggested naming convention is vsdnngvg_name. The length of the name must be less than or equal to 31 characters.
Note: If you specify a vsd_name that is already the name of another device, the cfgvsd command will be unsuccessful for that virtual shared disk. This error ensures that the special device files created for the name do not overlay and destroy files of the same name representing some other device type (such as a logical volume).

Security

You must have root authority to run this command.

Restrictions

You must issue this command from a node in the peer domain that has an active recoverable virtual shared disk subsystem.

Examples

To fence the virtual shared disks vsd1 and vsd2 from node 5, enter:

fencevsd -v vsd1,vsd2 -n 5

Location

/opt/rsct/vsd/bin/fencevsd