You hot-add a drive that contained previous configuration information to a system.
Make sure the inserted drive is usable.
Do not power down the system when hot adding drive to an existing system.
Add drives to system one drive at a time. Give enough time for drive to be recognized by the system.
Do one of the followings according to your system:
After each drive insertion, check the MEL to insure that the drive has been added. If there are any errors while adding drives, check the Recovery Guru and follow Recovery Guru procedures to fix any problems prior to adding additional drives