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Snapshots are NOT backups

A virtual machine snapshot is not a copy so it cannot be treated as a direct backup. A snapshot file is simply a log of changes to the original virtual disk. The virtual machine is running on the most current snapshot, not the original vmdk disk files. To reiterate: snapshots are not copies of the VM's original vmdk disk files. Taking a snapshot does not create a complete copy of the original vmdk disk file, rather it only copies the delta disks.

Side effects

...

of running with snapshots

• An excessive number of

  Decreased performance if there are too many delta files in a chain (caused by

  an excessive number of snapshots) or large delta files may cause decreased virtual machine and host performance. Not able to increase size of Virtual Disk

  having too many snapshots).

• Decreased performance if delta files become too large.

• Cannot increase Virtual Disk size while snapshots are active.

• Delta files can grow to the same size as the original base disk file

  , which is why the provisioned storage size of a virtual machine increases by an amount up to the original size of the virtual machine multiplied by the number of snapshots on the virtual machine.

Recommended Reading

• Understanding virtual machine snapshots in VMware ESXi and ESX (VMware KB Article 1015180)
• Best practices for virtual machine snapshots in the VMware environment (VMware KB Article 1025279)

• : a virtual machine's provisioned storage size can grow to ( its original size ) multiplied by ( the number of snapshots ).

Requesting a Snapshot

To request a snapshot for your VM, please use one of the following methods:

• fill out the following Snapshot Request form.
• use the EIS Virtual Cloud RESTful API - How to schedule a VM snapshot

  How-to Create Virtual Machine Snapshot

Reverting to a Snapshot

To revert a VM to (or from) a specific snapshot, please use one of the following options:

• send

  How-to Revert to Virtual Machine Snapshot  

Deleting a Snapshot

To delete a snapshot for your VM, please use one of the following methods:

• https://eis-vss.atlassian.net/wiki/spaces/VSSPublic/pages/1356922991/Manage+virtual+machine+snapshots#%5BinlineExtension%5D%5BinlineExtension%5DDelete

Consolidate Disks 

To consolidate VM disks, please use one of the following options:

• Use the VSS Command Line Interface 

• Use the ITS Private Cloud RESTful API

• Send an email to vss(at)eis.utoronto.ca

  .use the EIS Virtual Cloud RESTful API

Recommended Reading

• Understanding virtual machine snapshots in vSphere (VMware KB Article 1015180)

• Best practices for virtual machine snapshots in the VMware environment (VMware KB Article 1025279)

Snapshot Old Notification

• The ITS Private Cloud will notify periodically when a snapshot is not compliant with the 72 hour lifetime period.

• The Notifications will:

  • be ongoing until the deletion and will include the VM admin, informational contacts and the user who created the snapshot.

  • have the subject is Snapshot Old Detected

  • are sent on a daily basis until deleted