System in UEFI mode unbootable after changing motherboard

This document (7019031) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 11 Service Pack 1 (SLES 11 SP1)
SUSE Linux Enterprise Server 11 Service Pack 2 (SLES 11 SP2)
SUSE Linux Enterprise Server 11 Service Pack 3 (SLES 11 SP3)
SUSE Linux Enterprise Server 11 Service Pack 4 (SLES 11 SP4)
SUSE Linux Enterprise Server 12 Service Pack 1 (SLES 12 SP1)
SUSE Linux Enterprise Server 12 Service Pack 2 (SLES 12 SP2)

Situation

System fails to load EFI Linux Loader (elilo) or grub2 EFI bootloader after changing motherboard. EFI boot image is located on a block device that can be accessed when booted to rescue.

You may see the generic LILO prompt once the system fails to boot.

boot:

However, what you see may vary depending on the hardware in use.

When booted to rescue system, efibootmgr output shows that the SLES EFI boot entry is missing as shown below:

Rescue:~ # efibootmgr
BootCurrent: 0000
Timeout: 10 seconds
BootOrder: 0003,0000,0001,0002,0004,0005
Boot0000* CD/DVD Rom
Boot0001* Hard Disk 0
Boot0002* PXE Network
Boot0003* Windows Boot Manager
Boot0004* USB Storage
Boot0005* Diagnostics

Resolution

Boot system to installation media and select "Rescue System." Log in with root when prompted and chroot into the installed system.

See here for detailed instructions on chroot-ing into an existing system from rescue:
https://www.suse.com/support/kb/doc/?id=7018126
Once chrooted, check the /etc/fstab file for the /boot/efi entry and verify that the configured disk identifier exists. In some RAID configurations, the scsi disk ID may change when the motherboard is changed. Update disk ID(s) accordingly before proceeding.
Verify that the /boot/efi partition (and the /boot partition, if it's on its own separate partition) is mounted and that the data in the /boot/efi directory are accessible.
On SLES11
Run the following elilo command:

Rescue:~ # elilo --refresh-EBM

On SLES12
Run the following grub2 command:

Rescue:~ # grub2-install

This step will copy your EFI Linux Bootloader configuration files to the EFI partition under the "/boot/efi/efi/SuSE/" directory and write a new "SUSE Linux Enterprise Server ## SP#" or "sles" entry to the UEFI firmware on the motherboard.

Run efibootmgr once more to verify that a new SUSE Linux Enterprise Server or sles entry exists and that its boot ID is the first entry in the BootOrder row:

SLES11:

Rescue:~ # efibootmgr
BootCurrent: 0000
Timeout: 10 seconds
BootOrder: 0006,0003,0000,0001,0002,0004,0005
Boot0000* CD/DVD Rom
Boot0001* Hard Disk 0
Boot0002* PXE Network
Boot0003* Windows Boot Manager
Boot0004* USB Storage
Boot0005* Diagnostics
Boot0006* SUSE Linux Enterprise 11 Server SP3

SLES12:

Rescue:~ # efibootmgr
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0001,0003,0000,0008
Boot0000* UiApp
Boot0001* sles
Boot0003* UEFI QEMU DVD-ROM QM00001 
Boot0008* EFI Internal Shell

Reboot to test

Cause

The UEFI firmware on the motherboard stores the EFI boot configuration. If a motherboard is changed, the firmware on the new motherboard will need to have the system's EFI boot configuration written to it before the SLES system will be bootable.

Additional Information

Disclaimer

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