Toshiba Aquilion 64: RAW data disk (RDD) array fails with mixed drive types
What happened
Engineers reported that the RAW data disk (RDD) RAID array could not be made to work when drives of different types were mixed in one array.
What was checked
- Checked the installed drives and compared their capacities, interface and firmware versions, as described in the case.
- Reviewed the compatibility of drive types within a single RAID array for this model.
Cause
Reported in the case: the RDD array runs Fibre Channel drives of specific approved types with firmware 0003, and the 36 GB drive type (BSX73-1828E) is not compatible with the 73 GB (BSX73-2232E) and 300 GB (BSX73-2396E) drives in the same RAID.
What was done
As reported in the case, the engineers solved it by using only compatible drive types: 73 GB and 300 GB drives may be mixed in one array, the 36 GB drive may not, and each drive must carry firmware 0003. The array was then brought up on a consistent set of drives.
Safety
Power down and isolate the disk subsystem and follow ESD precautions before handling drives, and complete the manufacturer's functional checks, including a test acquisition and the electrical safety test, before the scanner returns to clinical use.
Lesson: In a RAID array, drive compatibility means more than capacity — interface and firmware must also match the approved specification, so verify the allowed drive types before mixing or fitting spares.
Covered in the course: CT Service — Level 2: Fault-Finding →
Written from an anonymised case shared by service engineers. It is not a manufacturer instruction and grants no authorisation. Independent note; names are trademarks of their owners.