When AVVI is enabled, you cannot manually delete a vCenter snapshot because when a snapshot is removed from a virtual machine, ESX automatically creates a Consolidated Helper-0 snapshot which holds the snapshot data until the actual snapshot is deleted. Once the process is complete, the Consolidated Helper-0 is rolled into the resulting .vmdk file only when the following conditions are met:
- Consolidated Helper-0 snapshot file size must meet the minimal snapshot size in VMware which is less than 16MB
- None or minimal I/O write on the virtual machine
To automatically delete a vCenter snapshots, log into the Barracuda Backup web interface, and go to the Backup > Schedules page.
If you attempt to manually delete a vCenter snapshot from Barracuda Backup before the Consolidated Helper-0 snapshot is rolled into the VMDK, an error displays in the Reports > Backup report page in the Barracuda Backup web interface, as shown in the following image:
Verify VMware Disk I/O Issues
If you continue to encounter an error, you may wish to confirm whether there are I/O issues on the virtual machine causing high CPU usage.
- Log into and restart the virtual machine to commit the Consolidated Helper-0 snapshot.
- Log into the vCenter/vSphere Snapshot Manager and create a quiesce snapshot file.
- Once the quiesce snapshot is created, click on the quiesce snapshot file name, and click Delete.
- When you delete the snapshot, if a Consolidate Helper-0 snapshot continues to display, and the Status field displays an error message similar to the following:
You may need to adjust your virtual environment to resolve the high CPU usage.
Unlock the quiesce Snapshot
Use the following steps to unlock the Consolidated Helper-0 file:
- Log into and restart the virtual machine.
- Allow the quiesce snapshot to commit the snapshot; the Consolidated Helper-0 file should be automatically removed once this process is complete.