The storage system holds up to 30 drives, which are numbered from left to right in rows starting from 0 at the top-left drive. Drive numbers increment from left to right, and then top to bottom such that the first row of drives is numbered from 0 to 4 from left to right, and the second row of drives is numbered from 5 to 9 from left to right.
Storage Manager identifies drives as XX-YY, where XX is the number of the unit ID of the storage system and YY is the drive position inside the storage system.