ELevate will fail during Stage 3 if Leapp is unable to determine the Partition type where GRUB is installed

Symptoms

As part of the ELevate process, the underlying Leapp application needs to make various changes to the bootloader of the server in order to successfully upgrade the server's OS. This will lead to errors like the following:

Risk Factor: high (error)
Title: Actor scan_grub_device_partition_layout unexpectedly terminated with exit code: 1
...
UnboundLocalError: local variable 'disk_type' referenced before assignment

This error occurs during Stage 3 of the ELevate process, and the process cannot continue.

Description

As part of the checks for the bootloader, the Leapp script reads the first 512 bytes of each disk that has a `/boot` partition to check for the GRUB signature. If the server uses a RAID and `/boot` is found in the RAID, then all disks associated with the RAID are checked as well.

For all disks found that have the GRUB signature, further queries are performed to determine the partition type, and retrieve the map of the current partitions on the disk. However, if the disk does not its Master Boot Record setup correct (MBR), the partition type is not defined and thus the script fails.

We've opened an internal case for our development team to investigate this further. For reference, the case number is RE-1485. Follow this article to receive an email notification when a solution is published in the product. 

Workaround

There is currently no workaround for this issue.  If your server becomes impacted by this, it would be advised to restore the server from a backup from before the ELevate was performed, and instead perform a transfer to a new server.

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