Specifies that BACKUP is to ignore any volume structure on the
    input device and is to process the volume in terms of physical
    blocks. If you write a save set with the BACKUP/PHYSICAL command,
    you must also restore it with the BACKUP/PHYSICAL command.

    For physical copy operations between disks, the output device
    must be either the same size or a larger-capacity disk.

    If the output device is larger than the input device, only disk
    blocks less than the size of the input device are written to the
    output device. Depending on the volume structure of the input
    device, the extra uninitialized blocks at the end of the output
    device might create an unusable disk volume.

    If the input device contains a FILES-11 ODS-2 or ODS-5 volume,
    you can expand the volume size on the output device after the
    restore by using the DCL command SET VOLUME/LIMIT/SIZE.

    For all physical operations, the output disk cannot have a bad
    block in any location that corresponds to a good block on the
    input disk. (This restriction does not apply to RA or more recent
    disk architectures.)