The presence of redundant delta disks can adversely affect virtual machine performance. You can combine such disks without violating a data dependency. After consolidation, redundant disks are removed, which improves virtual machine performance and saves storage space.
Snapshot consolidation is useful when snapshot disks fail to compress after a Delete or Delete all operation. This might happen, for example, if you delete a snapshot but its associated disk does not commit back to the base disk.
The Needs Consolidation column in the vSphere Web Client shows the virtual machines to consolidate.
- Show the Needs Consolidation column.
- Select a vCenter Server instance, a host, or a cluster and click the VMs tab and click Virtual Machines.
- Right-click the menu bar for any virtual machine column and select .
A Yes status indicates that the snapshot files for the virtual machine should be consolidated, and that the virtual machine's Tasks and Events tab shows a configuration problem. A No status indicates that the files are OK.
- To consolidate the files, right-click the virtual machine and select .
- Check the Needs Consolidation column to verify that the task succeeded.
If the task succeeded, a Not Required value appears in the Needs Consolidation column.
- If the task failed, check the event log for failed conditions, such as running out of disk space.
- Correct the error, and retry the consolidation task.
The configuration problem is resolved, and the Needs Consolidation value is Not Required.