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Recovering a UEFI image

Use this information to recover a UEFI image.

The compute node has an advanced recovery feature that automatically switches to a backup UEFI page if the UEFI code in the compute node has become damaged, such as from a power failure during an update. The flash memory of the compute node consists of a primary page and a backup page. If the UEFI code in the primary page is damaged, the integrated management module detects the error and automatically switches to the backup page to start the compute node. If this happens, a POST message Booted from backup UEFI image is displayed, the check log LED is lit, and an automatic BIOS recovery (ABR) condition occurs. The backup page version might not be the same as the primary page version.

You can then recover or restore the original primary page UEFI.

Note
Changes are made periodically to the Lenovo website. The actual procedure might vary slightly from what is described in this document.

To recover the UEFI code and restore the compute node operation to the primary page, complete the following steps:

  1. Update the UEFI code (see Updating firmware and device drivers).
  2. Restart the compute node.
  3. At the firmware splash screen, press F3 when prompted to restore to the primary bank. The compute node boots from the primary bank.
    Note
    The prompt to press F3 displays only if the compute node boots from the backup page due to an ABR condition.
If the attempt to flash the primary page results in the compute node not booting and the check log LED is not lit, you can manually restore the UEFI code. To manually restore the UEFI code, complete the following steps.
Note
If the check log LED is lit, the compute node is booting from the backup image and moving the switch to backup changes nothing.
  1. Before you begin, read Safety and Installation guidelines.
  2. Turn off the compute node (see Turning off the compute node).
  3. Remove the compute node from the Lenovo Flex System chassis (see Removing a compute node from a chassis).
  4. Remove the cover (see Removing the compute node cover).
  5. Locate the boot backup UEFI switch on the switch block and move the switch to the On position (see System-board switches).
  6. Replace the cover and reinstall the compute node in the Lenovo Flex System chassis (see Installing the compute node cover and Installing a compute node in a chassis).
  7. Update the UEFI code (see Updating firmware and device drivers).
  8. Turn off the compute node and remove it from the Lenovo Flex System chassis (see Turning off the compute node and Removing a compute node from a chassis).
  9. Remove the cover of the compute node (see Removing the compute node cover).
  10. Locate the boot backup UEFI switch on the switch block and move the switch to the Off position (see System-board switches).
  11. Replace the cover and reinstall the compute node in the Lenovo Flex System chassis (see Installing the compute node cover and Installing a compute node in a chassis).
  12. Restart the compute node (see Turning on the compute node).
Important
If you are unable to manually restore the UEFI code after several attempts, replace the system-board assembly (see Removing the system-board components for base-assembly replacement and Installing the system-board components for base-assembly replacement).