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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.

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The keys currently assigned to disks can be displayed by using the vxfenadm command.

For example, from the system with node ID 1, display the key for the disk /dev/rhdisk74 by entering:

# vxfenadm -g /dev/rhdisk74

Reading SCSI Registration Keys...

Device Name: /dev/rhdisk74

Total Number of Keys: 1

key[0]:

Key Value [Numeric Format]: 65,45,45,45,45,45,45,45

Key Value [Character Format]: A-------

The -g option of vxfenadm displays all 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 letters of the key, in this case, "-------". In the next line, the node ID 0 is expressed as "A;" node ID 1 would be "B."