An access volume is a factory-configured volume on the storage array that is used for communication with the storage array and the host through the host I/O connection. The access volume requires a Logical Unit Number (LUN).
The access volume is used in two instances:
Automatic host creation — The access volume is used by the Host Context Agent (HCA) utility to push host information (name, ports, host type) to System Manager for automatic host creation.
An access volume is automatically created the first time you assign a volume to a host. For example, if you assign Volume_1 and Volume_2 to a host, when you view results of that assignment, you see three volumes (Volume_1, Volume_2, and Access).
If you are not automatically creating hosts or managing a storage array in-band with the CLI, you do not need the access volume, and you can free up the LUN by deleting the access volume. This action removes the volume-to-LUN assignment as well as any in-band management connections to the host.