To create a snapshot, follow these steps:
- From vSphere Client, right-click the VM you want to process and select Snapshots | Take Snapshot.
- Enter a name and provide a description. If the VM is powered on during the snapshot creation, you have the option to Snapshot the virtual machine's memory (grayed out if the VM is off). If this option is enabled, the RAM of the VM is also included in the snapshot.
Not implemented in the HTML5-based client yet, vSphere Web Client has an additional Quiesce guest file system (Needs VMware Tools installed) option that brings the on-disk data into a state suitable for backups, ensuring consistent and working backups. This option is available if VMware Tools is installed on the VM:
Assign a meaningful name to easily identify the snapshot
- Click OK to take a snapshot of the selected VM.
When a snapshot is taken, multiple new files are created in the VM folder—.vmdk, -delta.vmdk, .vmsd, and .vmsn files:
Files created when a snapshot is taken
Let's have a look at the files created when a snapshot is taken and the role they have:
- vmname-00000#.vmdk: This is a text file that contains info about the snapshot and snapshot disks. For every snapshot taken, the file is created for each of the .vmdk files.
- vmname-00000#-delta.vmdk: This is the delta disk file that represents the difference between the current state of the VM and the state at the time of snapshot creation.
- vmname.vmsd: This file holds snapshot information such as names, descriptions, and relationships between snapshots.
- vmname.snasphot#.vmsn: This stores the memory state of the VM when the snapshot is taken and it is created each time you take a snapshot.