Inform users about VMware Virtual Machine (VM) Backup failures because of not being able to create snapshots and FileAlreadyExists errors.
The Backups of one or more VMs fail due to the inability to create snapshots. Unitrends needs to create snapshot of a VM in order to perform the Backup of the same. If there are some errors thrown from VMware/ESX Host side during this operation, then Unitrends fails those Backups. FileAlreadyExists error is seen in the Backup error messages.
For more detailed information on backup failures and performance issues see Unitrends KB 5062 - Backup Failures and Performance Issues
To resolve this issue:
- Locate and manually rename or move the “-delta.vmdk” file that does not have an associated descriptor file.
For more information on the steps, refer to the following VMware KB.
This can happen if “-delta.vmdk” file already exists in the inventory for that VM. When the ESX host tries to create the snapshot, it first creates the new descriptor file, then creates the associated “-delta.vmdk” file. If the ESX host detects that a “delta.vmdk” file with that name already exists the snapshot operation fails and the virtual machine reverts to its previous state.