Option 2: Manually Revert Original VM Disk Configuration
If you want to revert the original VM to its pre-Failback state, you will perform a variation on the "Alternative procedure" from VMware KB: 1007969, described below. This procedure involves disconnecting the snapshot disks and reattaching the original base disks, somewhat similar to Veeam KB1773, except that instead of modifying the Replica's disks, you'll modify the Original VM. Performing this will cause all data within the snapshots on the Original VM to be lost, including data that was present in a snapshot created before the Planned Failover and Failback.
If you are uncomfortable completing these steps, please stop and create a case with Veeam Support referencing this KB.
- Edit the original VM using the vSphere client.
- Note the SCSI node assignments for each disk file and the location of those disk files.
SCSI0:0 = [Datastore1] DC01\DC01-000001.vmdk
SCSI0:1 = [Datastore1] DC01\DC01_1-000001.vmdk
SCSI0:2 = [Datastore2] DC01\DC01-000001.vmdk
Detach Snapshot Disks and Attach Base Disks
- Edit the Original VM, and detach/remove each of the snapshot disks.
- After removing all of the snapshot disks from the Original VM, edit it again and reattach the base disks to each SCSI node.
- Select the Add Existing Hard Disk option, then navigate to the location of the base disk.
- After the disk is attached, assign the correct SCSI node based on the path and VMDK file name.
For example, if the snapshot disk [Datastore1] DC01\DC01-000001.vmdk was using SCSI0:0, then the base disk would be
SCSI0:0 = [Datastore1] DC01\DC01.vmdk and it should be assigned to that same SCSI node.
- Repeat the above 2 steps to attach each of the base disks to the same SCSI nodes noted earlier.
- Using the datastore browser, navigate to the Original VM's folder.
- Delete all child disk files created by the snapshot (vmname-000###.vmdk) and any –ctk.vmdk files. Also, delete VMSN and VMSD files.
- If there were multiple datastore folders among the disks, check those other datastores as well.
Test the VM
- Create a snapshot on the Original VM.
- Open the Snapshot Manager and click the Delete All button.
- If the Snapshot Removal completes without error, the disks are reverted.
If you completed the procedure correctly, the Original VM should now be in the same state it was in before the Failback. You may now proceed with reattempting the Failback procedure if you want to synchronize the Replica's state over the Original VM.
Note: If the previous Failback operation failed, you should create a case with Veeam Support to investigate why that Failback failed. The procedure documented above will only fix the Original VM. It will not correct the underlying reason the Failback failed.