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Verifying fenced configurations

Administrators can use the vxfenadm command to test and troubleshoot fenced configurations. Command options include:

-d display current I/O fencing mode

-g  read and display keys

-i  read SCSI inquiry information from device

-m  register with disks

-n  make a reservation with disks

-p  remove registrations made by other systems

-r  read reservations

-x  remove registrations

Registration key formatting

The key defined by VxVM associated with a disk group consists of seven bytes maximum. This key becomes unique among the systems when the VxVM prefixes it with the ID of the system. The key used for I/O fencing, therefore, consists of eight bytes.

The keys currently assigned to disks can be displayed by using the command
vxfenadm -g /dev/device_name command. For example, from the system with node ID 1, display the key for the device_name by entering:

# vxfenadm -g /dev/device_name

Reading SCSI Registration Keys...

Device Name: device_name

Total Number of Keys: 1

key[0]:

Key Value [Numeric Format]: 65,80,71,82,48,48,48,48

The -g option of vxfenadm displays the eight bytes of a key value in two formats. In the numeric format, the first byte, representing the node ID, contains the system ID plus 65. The remaining bytes contain the ASCII values of the key's letters. In this case, "PGR0000." In the next line, the node ID 0 is expressed as "A" and node ID 1 would be "B."