$ sudo virsh list
 Id   Name                           State
----------------------------------------------
 2    puppet-environment_pergamon    running
 4    puppet-environment_riverside   running
 5    puppet-environment_admin-rp1   running

$ sudo virsh snapshot-create-as puppet-environment_admin-rp1 --name rp1-prior-riverside-migration
Domain snapshot rp1-prior-riverside-migration created
$ sudo virsh snapshot-list puppet-environment_admin-rp1
 Name                            Creation Time               State
----------------------------------------------------------------------
 rp1-prior-riverside-migration   2022-01-27 10:11:24 +0100   running
 rp1-snapshot                    2022-01-27 09:52:42 +0100   running
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