Blade Storage expansion may resync during cold boot - IBM BladeCenter

Resolving The Problem

Source

RETAIN tip: H195233

Symptom

BladeCenter HS20, Type 8843, with Blade Storage Expansion (BSE) may resync during cold boot of the blade.

The blade will only have a total of two (2) hard drives installed of 300 gigabytes (GB) Hitachi options as a Redundant Array of Independent Disks (RAID) mirror. The drives may randomly go into a resync state even when fully synchronized prior to shut down. The failure is not seen when other drives are installed on the base system board or use of another vendor drive is used in the SCSI storage expansion.

Affected configurations

The system may be any of the following IBM Servers:

• BladeCenter HS20, type 1883, any model
• BladeCenter HS20, type 8843, any model

This tip is not software specific.

This tip is not option specific.

Workaround

Failures have not been seen when using another vendor drive in the SCSI expansion. The user may also use a third drive on the base blade to prevent this failure from occurring.

Additional information

This is a hardware limitation of the 8843 blade.

The BSE SCSI expansion for the 8843 blade was found to be floating the SCSI IDs. This causes only Hitachi drives to re-ID themselves during a cold boot. By receiving a new SCSI ID, the LSI controller now sees that the Mirror has changed and begins to resync.