i started that way usb hdd, and now i have changed to NAS solution with CIFS, yesterday I had a problem with nextcloud restaure confs and data, flawless all up and running after 25 min of restaure,… but i need hotsync to make an second nethserver in case of machine failure(nethserver my main router at home)…
If it is to have a safe remote storage, I strongly suggest to use a cloud soluition for that. Preferably by using a VPS so you have full control over the storage.
AFAIK NethServer backup uses encryption, so IF the backup ever gets compromised in some way, a key is needed to decrypt the backup.
Besides that you could add an extra layer of encryption by using a (veracrypt) container where you backup to… (that’s what I do with the database for my password manager)
IMVHO the different label causes errors when the cartdrige is changed and needs a fix for the destination of the backup.
adding the small file into the root dir of the drive will allow from console/ssh to correctly identify which cartdrige is inserted.
OR…
Maybe you can also workaround creating a backup profile for each cartdrige, but in this way you will generate N-1 errors for any schedule, with N as the number of cartdrige available.