Smart Array backplane RAID controllers using parallel
                SCSI expect to be connected to enclosures that have
                individual built in enclosure processors. These
                processors or Environmental Monitoring Units (EMUs)
                monitor fans, control LEDs and so on. The EMUs also
                provide information about hot-plug events available
                in the enclosure. The Smart Array controller is thus
                always aware of the insertion or removal of a SCSI disk
                drive when used with such type of enclosures, like MSA30.

                The 64xx series Smart Array card can also be cabled to
                the internal parallel SCSI drives on applicable I64
                platforms. These drives are housed in an enclosure that
                is totally passive with respect to hot-plug event
                notification. The Smart Array controller cannot detect
                that a physical disk has been hot-inserted. If a RAID
                physical disk fails and must be replaced, the controller
                will not start the recovery process on the affected RAID
                volumes.

                SCAN ALL command sends a SCAN message to the Smart Array
                controller instructing the controller to scan SCSI buses and
                discover new or replaced disk(s). After the SCAN is complete,
                the REBUILD operation for the logical volumes will be
                initiated for all the UNITs configured in the disk group.

                This command is only applicable for the internal disk
                enclosure connected to the Smart Array on I64 platforms.

                Note: Refer to START RECOVER command for additional
                      information on rebuild of volumes.