Degraded RAID 5 Rebuild and Recovery.
A customer reported a hard disk drive crash on their Dell PowerEdge RAID 5 server this week with a single drive drop-out from the Array. They hadn’t noticed a drop in system performance but were having difficulty restoring the fault logs and status indicators
Datlabs emergency RAID support team noted a hard drive had dropped out of the array and replaced this with a new compatible drive and the array was allowed to auto rebuild. Once the rebuild was complete however, the system status remained degraded and error code 2094 in the OpenManage log alerts.
The team examined the PERC 4/Di controller self-monitoring analysis and reporting logs. The technology uses (SMART) to predict drive failures. SMART monitors the internal performance of all motors, heads, and hard drive electronics. During their checks they noted the SMART log of the replacement drive was throwing up bad sector reports with a predictive failure. Replacing this drive once more and undertaking a rebuild returned the system to full working order.
To get out of degraded mode on the PERC 4/di controller .
- Remove the failed hard drive.
- Replace with a new compatible hard drive
- Let the system automatically rebuild the array
- If the rebuild goes to 100% but still is still showing as degraded.
- Clear all logs
- Clear the alert log
- Do a complete system re-scan
nb. Preventative checks are much easier to deal with than attempting to rebuild a RAID 5 System from the ground up.
If all else fails Datlabs Emergency RAID support team are on hand team to sort out your difficulties and get you up and running again.