What were you trying to do that didn't work?

• Performed RHEL 7.9 to RHEL 8.10 upgrade. It was a VM on VMWare
• Post upgrade server failed to boot, landing in grub_rescue> prompt

• error: ../../grub-core/fs/fshelp.c:258:file `/grub2/i386-pc/normal.mod' not found.  
  Entering rescue mode
  grub rescue>

• Steps taken to resolve the issue and isolate the issue:

• • Booted the server in rescue mode.
  • Enabled networking
  • Downgraded grub2 packages # yum downgrade grub2-pc
  • Reinstalled GRUB on /dev/sda # grub2-install /dev/sda
  • Rebooted the server and booted it from OS disk
  • The server came up without any issues.
  • Updated the grub2 packages # yum update grub2
  • Rebooted the server, it came up without any issues.
  • Installed GRUB2 on /dev/sda # grub2-install /dev/sda
  • Rebooted the server, it failed to boot, landing in grub_rescue> prompt

NOTE: I could not reproduce the issue on a KVM VM. Steps taken to reproduce the issue.

• I had RHEL 8.10 server installed using RHEL 8.10
• Updated grub2 packages, reinstalled GRUB2 on the disk, rebooted the server, the server came up without any issues.
• Updated the all the packages using "yum update", reinstalled GRUB2 on disk, rebooted the server, it came up without any issues.

Workaround:

• Boot the server in rescue mode.
• Enable networking
• Downgrade grub2 packages # yum downgrade grub2-pc
• Reinstall GRUB2 on disk # grub2-install /dev/<disk>
• Reboot the server from OS disk

What is the impact of this issue to you?

• Multiple customers are facing the same issue.

  Please provide the package NVR for which the bug is seen:

grub2-common-2.02-162.el8_10.noarch                       
grub2-pc-2.02-162.el8_10.x86_64                             
grub2-pc-modules-2.02-162.el8_10.noarch                     
grub2-tools-2.02-162.el8_10.x86_64                         
grub2-tools-extra-2.02-162.el8_10.x86_64                   
grub2-tools-minimal-2.02-162.el8_10.x86_64                  
grubby-8.40-49.el8.x86_64    

How reproducible is this bug?:

After RHEL 7.9 to RHEL 8.10 in-place upgrade.

Steps to reproduce

1. Update the RHEL 8 server to RHEL 8.10 latest updates
2. Reinstall GRUB2: # grub2-install <disk>
3. Reboot the server.

Expected results:

• The server should boot without any issues.

  Actual results:

• The server fails to boot, landing in grub_rescue> prompt