Is there a recommended method to backup the data?
Are you using VirtualBox? If so you can always just take snapshots of your VM.
I am using KVM and an external USB drive.
Looks like KVM can take snapshots too
I am nowhere near an expert with KVM or hypervisors though…I just generally find snapshots to be useful for my cloud servers and what not
KVM snapshots are for the complete VM. I used tar and the shared folder to backup the data.
How to backup a KVM VM?
I mean, unrelated to Whonix, unspecific to Whonix.