Unable to restore virtual machines (VMs) from the Avamar backup application. The restore process fails at an early stage due to VMX File Update Error.

Products

• VMware vCenter Server

Issue/Introduction

• Restoring virtual machines (VMs) using the Avamar backup application. The restore process consistently failed at an early stage, preventing VM recovery operations. Upon investigation, the Avamar restore window displayed errors related to VM creation failures.

• Avamar backup logs indicated failures specifically tied to updating the VMX configuration file during restore, as shown by error messages:

YY-MM-DD H:M:S BackupServer Info <41150>: Request to create vm name XXXXXXX_Restore.
YY-MM-DD H:M:S BackupServer Error <17772>: Failed to update the contents of the VMX file.
YY-MM-DD H:M:S BackupServer Error <0000>: [XXXXXX] VM creation failed during restore.
YY-MM-DD H:M:S BackupServer Info <9772>: Starting graceful (staged) termination, Create VM failed during restore. (wrap-up stage)

 

Cause

The failure stems from Avamar being unable to update the VMX file metadata appropriately due to inconsistencies introduced by V2V conversion and generic disk naming conventions.

• Their virtual disk files (VMDKs) used generic naming such as disk0.vmdk, disk1.vmdk, instead of a VM-specific naming convention (e.g., VMname.vmdk).
• The problematic VMs had been converted from Hyper-V to VMware (V2V migration), which can produce VM configurations incompatible with Avamar’s restore mechanism.

Resolution

To resolve this issue, Initiate a Storage vMotion and rename the .vmdk's to different name. 

Note: Before starting the Storage vMotion ensure the vmdk's name are changed.

This approach resolves the VMX file update issues because cloning resets disk file names and configuration metadata to a state compatible with Avamar’s restore process. 

Disclaimer: Please, ensure we have a validate backup's.