/DISK=sas_id(,...)

    This qualifier is required. Specifies the SAS ID of the physical
    disk to be added to the IR volume set. (The SAS ID is the ID
    shown when you enter the SAS command SHOW DISK.) Enclose multiple
    SAS IDs in parentheses.

    The effective size of the RAID volume is automatically determined
    and set to the maximum size available. The firmware supports
    disks of varying sizes; however, the excess space of a larger
    disk or disks is unusable. Volume expansion is not supported;
    once a volume is created, its size cannot be increased.

    A physical disk must be dismounted in OpenVMS before it can be
    added to the IR volume set.