System hangs when invalid GPT detected - IBM Flex System and System x

Resolving The Problem

Source

RETAIN tip: H212861

Symptom

System will hang during Power On Self Test (POST) when a GUID Partition Table (GPT) partition table was found to be corrupted.

Normally this is an extremely rare event. However, certain Redundant Array of Independent Disks (RAID) operations can present an invalid GPT. If disks that have a GPT partition and are used when creating a new RAID array that has a different size than the original disk and the default of leaving the disk contents alone is used, this will create a GPT that looks corrupted.

Affected configurations

The system may be any of the following IBM servers:

• Flex System x480 X6 Compute Node, type 7903 , any model
• Flex System x880 X6 Compute Node, type 4259, any model
• System x3850 X6, type 3837 (4-socket, 3-year warranty), any model
• System x3850 X6, type 3839 (4-socket, 4-year warranty), any model
• System x3950 X6, type 3837 (8-socket, 3-year warranty), any model
• System x3950 X6, type 3839 (8-socket, 4-year warranty), any model

This tip is not software specific.

This tip is not option specific.

The following system BIOS or UEFI level(s) are affected:

• Build IDs:
  • A8E104x, A8107LUS, N2E107MUS

Solution

This behavior will be corrected in a future release of UEFI firmware.

The target date for this release is scheduled for first quarter 2015.

The file is or will be available by selecting the appropriate Product Group, type of System, Product name, Product machine type, and Operating system on IBM Support's Fix Central web page, at the following URL:

• http://www.ibm.com/support/fixcentral/

Workaround

When a hang occurs after creating a RAID volume on reused disks, perform the following:

1. Power off the system.
   
2. Remove the disks from the system.
   
3. Reboot the system and enter F1 setup.
   
4. At this point, reinsert the disks.
   
5. Enter the RAID controller settings and Select delete the array.
   
6. Recreate the array using Create Advanced, and select Initialize, FAST. This will clear the stale GPT contents from the disk.
   

Additional information

Debug code was inadvertently left in the UEFI firmware.