VMW0052: Backup snapshot completes successfully but snapshot and disk files are not cleaned up (VMware)

Symptom

When performing a backup of a virtual machine, the backup takes a long time to complete, but does complete successfully. After the backup, the snapshot and virtual machine disks remain on the datastore.

The following message appears in the vsbkp.log file:

 
Exception while waiting for task task_ID - The operation has timed out

Cause

If a virtual machine is being backed up when a Storage vMotion request is made to migrate the virtual machine to another datastore, or if a Storage vMotion is in progress when a backup request arrives, the backup is delayed. When both tasks are completed, the snapshot and virtual machine disks remain on the original datastore.

This issue can occur when using vCenter Server 5.1, vCenter Server 5.1 Update 1, or vCenter Server 5.5 versions earlier than 5.5 Update 2, with virtual machines residing on datastores that are part of a Storage Distributed Resource Scheduler (SDRS) cluster. More detailed information about the issue is available at An orphaned VMDK is created when a system or user generated vSphere Storage vMotion task is performed during virtual machine backup (2055943).

The issue is resolved in vCenter Server 5.5 Update 2 and later.

Resolution

For each VSA proxy, configure the bDisableVMotionDuringBackup setting to disable Storage vMotion during backups:

1. From the CommCell Browser, go to Client Computers.

2. Right-click the client for the VSA proxy and select Properties.

3. On the General tab of the Client Computer Properties dialog, click Advanced.

4. On the Advanced Client Properties dialog, click the Additional Settings tab.

5. Click Add.

6. Add the following entry:

   • Name: bDisableVMotionDuringBackup

   • Category: VirtualServer

   • Type: Boolean

   • Value: true (to disable Storage vMotion during backups)

7. Click OK to save the additional setting.

8. Click OK twice more to save the advanced client properties and the client properties.

When bDisableVMotionDuringBackup is set to true, Storage vMotion is disabled while a backup is in progress. The Storage vMotion request can be resubmitted when the backup completes or if the backup job is killed.

If a migration is already in progress, a backup request goes to a pending state until the Storage vMotion operation completes. For a backup job that includes multiple VMs, a VM that is being migrated is skipped and the other VMs are processed first.