You can plug in the data drive from your HASSOS machine to another computer and copy the snapshot out of it before reimaging the drive.
Ooooooor more usefully and realistically, if you hit update and it detects you haven’t done a backup, it could make a backup and then prompt you to save it to another computer.
Could even have the supervisor keep track of when each snapshot was downloaded last so if you made a backup yesterday but didn’t download it, it prompts you to download it before the update.
Now that HASSOS supports using a separate drive for your data volume, separating that out from the same drive as HASSOS is installed on can provide a little security here too, since you could re-image the boot drive without erasing the data volume, but it doesn’t protect against the update failing in a way that corrupts data on mounted storage.
I’m upvoting this cause I think that even just reminding people to make and download a backup before updates is a sensible move, even if they then have to do it themselves, cause it’s easy to slip the mind of the average user, and home assistant is all about making the smart home accessible to all
I’d also love if you could set a SMB or NFS share as the target director for snapshots, so it auto uploads them to somewhere else whenever you do one.