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When needed, the entire VM can be restored in place (overwrite) or along-side (keep) the original, as long as there are enough resources available within the VDC.
When overwriting, the source VM is first deleted from the VDC and the backup is written in its place.
When keeping the source VM, the backed up VM will be placed back into the same VDC and storage policy it was originally backed up from. Adequate space must be available within the original storage policy otherwise the restore task will fail.