Red Hat Enterprise Linux VM fails to boot with grubx64.efi Not Found error

Products

• VMware vSphere ESX 8.x

Issue/Introduction

• A Red Hat Enterprise Linux (RHEL) virtual machine running on ESXi 8.x fails to boot. The virtual machine console displays the following UEFI boot errors:
  
  Failed to open \EFI\redhat\grubx64.efi - Not Found
Failed to load image \EFI\redhat\grubx64.efi: Not Found
start_image() returned Not Found, falling back to default loader
  
  
• Upon entering Red Hat recovery mode and inspecting the installed packages, a large number of Rocky Linux RPMs from the "Rocky Enterprise Software Foundation" are found to be present in the system instead of standard Red Hat Enterprise Linux packages. Affected packages include grub2-efi-x64, grub2-common, and various system libraries.
• ESXi host logs and virtual machine logs (vmware.log) show no infrastructure-level failures or hardware virtualization errors.

Environment

VMware vSphere ESXi 8.x

Cause

The boot failure is caused by an unsupported Guest OS state where original Red Hat packages have been replaced or overwritten by Rocky Linux packages (likely due to an incomplete or unintended OS migration script). The UEFI bootloader is looking for the Red Hat specific path (\EFI\redhat\), which no longer exists or is invalid due to the presence of Rocky Linux GRUB configurations. This is a Guest OS software integrity issue and is not a failure of the VMware hypervisor.

Resolution

This issue is isolated to the Red Hat Enterprise Linux Guest OS and is not a vSphere hypervisor or virtual hardware defect.

1. Verify Backups: Ensure a valid backup or snapshot of the VM exists before attempting OS-level repairs.

2. Engage OS Vendor: Contact Red Hat Global Support Services to perform a root cause analysis on the package divergence and to assist with restoring the grub2 configuration and Red Hat repositories.

3. Recovery Attempt: If data is critical, mount the virtual disk to a healthy RHEL VM to retrieve files, as the current OS environment is in a non-deterministic state between RHEL and Rocky Linux.