In most cases you can use tools provided by your Virtual Machine Host to create a Backup and/or Snapshot of the installed VCL.
Understanding VM snapshots in ESXi / ESX
How to create Checkpoint with Hyper-V
Take a Snapshot in the vSphere Client
All the changes made after Snapshot was made will not be recovered, it is recommended to keep snapshot/checkpoints up to date.
You can also use Other backup solutions to Backup whole virtualization Platform.