Datastore performance is low and snapshot deletion/consolidation is timed out.VSphere may report that consolidation is needed in case there is a snapshot on the disk which should be deleted, but the deletion process is stuck in the Consolidation state for one of the following reasons: You would then run the snapshot consolidation option and the snapshot would get committed.This monitor tracks the vCenter alarm that is triggered when virtual machine Consolidation Needed status is set.īy default, the alarm is triggered by the following events: With the consolidation option, when you initiate a snapshot deletion, if the snapshot fails to delete, the VM will then generate a warning letting you know that a consolidation is required. In the past there were incidents where a user would initiate a snapshot deletion thinking the snapshot got deleted, yet to find out later that that’s not the case.

The purpose of consolidate is if the snapshot deletion process was not successful. With vSphere 5, a new option called consolidate was introduced. When initiating a snapshot delete action, the delta disk changes are then written to the base or parent VMDK file and the snapshot is deleted. After consolidation, redundant disks are removed, which improves virtual machine performance and saves storage space. The snapshot Consolidation searches for hierarchies or delta disks to combine without violating data dependency. This might happen, for example, if you delete a snapshot but its associated disk does not commit back to the base disk. Snapshot consolidation is useful when snapshot disks fail to compact after a Delete or Delete all operation or if the disk did not consolidate. When you delete the base parent snapshot, all changes merge with the base virtual machine disk. Deleting a snapshot consolidates the changes between snapshots and previous disk states and writes to the parent disk all data from the delta disk that contains the information about the deleted snapshot. The snapshot files are consolidated and written to the parent snapshot disk and merge with the virtual machine base disk.ĭeleting a snapshot leaves the current state of the virtual machine or any other snapshot untouched.