GE Brightspeed: DARC boot hang after fitting new disks
What happened
After new disks were connected to the DARC (reconstruction data archive) computer, the system hung during the disk BIOS enumeration at startup, and there was uncertainty about the correct disk configuration.
What was checked
- Confirm the DARC disk layout against the manufacturer's documentation — in this case reported as three drives (one 40 GB IDE and two 36 GB SCSI), not combined into RAID.
- Check how each replacement SCSI drive is addressed; some drives take their ID from their position on the cable rather than from on-drive settings.
- Compare the boot order given in the manual for this host with the actual BIOS settings.
Cause
The engineers found that the replacement SCSI drive carried a factory address setting that made the drive BIOS hang during enumeration, while the original drives had no such setting. The DARC disks are not in RAID, so each drive is enumerated individually and one bad drive can stall the whole boot.
What was done
The fix was a procedure from the manufacturer's service documentation, done by authorised personnel: the new drive's factory address setting was corrected so the disk BIOS enumerated all drives normally. Reported configuration in this case: three drives (40 GB IDE plus two 36 GB SCSI), not in RAID, with the boot order taken from the manual.
Safety
Power down and isolate the system before opening the DARC chassis, follow the manufacturer's ESD precautions, and remember these drives are not RAID-protected — back up archive data per procedure before any work on the disks.
Lesson: Before blaming a new drive or the host BIOS, compare the replacement drive's factory address and configuration settings with the original drives and verify the documented boot order.
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.