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Snapshots can be named however you like. Also you can take as many as you like, to save different states of the Opal server.
For example, you could take Snapshot 1 straight after importing the Opal server, and then later Snapshot 2 after uploading some of your own simulated data.
Implications on shutting down VMs
If you have followed the above instructions to create a snapshot, it will mean you will have the option to save the machine state as you shut down.
For general users, who have made no changes to the VM, there is no need to do this so shut down without checking the box:
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However if you have made changes you don’t want to save, select Power off the machine and check the box marked Restore current snapshot .