How do i create a image backup of the nextbox?
just in case and how would i restore?
Yes, but i believe this is about a backup of a already initiated instance. i would want to “clone the drive” and be able to go back to “virgin state”
a safety net for recovering from failed experiments if you will
Ah, ok I understand, cloning the drive(s) (you would have to clone the sd-card and the hard-drive) is not supported currently, but also not needed.
To return your NextBox to a “virgin state” you can factory-reset the NextBox as described here: Factory Reset — Nitrokey Documentation .
i think the term “factory reset of the nextbox” is misleading here. As i observed the underlying OS is not reset. So in fact it is only a reset of the nextcloud system and maybe the configuration which the nextbox-app does.
If my observations are correct, please clearify this in the Documentation, cause miss interpretation may lead to severe damage, if some users depend on it.
Well, depending on what you actually mean with “OS is not reset” you are right 
But clearly: “factory reset” is a simplification of the applied process, but I am with you, more details are always better. I added a todo for the documentation to be more precise here: https://github.com/Nitrokey/nitrokey-documentation/issues/38
yeah, that sounds fine to me.
As i am just testing the backup and restore process right now, i would also suggest to say a word about the fact, that the backup contains nothing about the installed apps and it is necessary to manually remember them and install them again before restoring the backup. Or is there any way to reconstruct the needed apps from the Backup?
yes, the backup/restore process is also to be documented in detail, see the link above