Backing up the backup files

There are other parts for best results, and some for any. For example, if you have encrypted the files and lost the passphrase, that’s irrecoverable. Doing an export and safe storage of the configuration can help there, and also avoids having to guess and enter what source files to include to continue with the backup.

The local database that tracks what’s in the backup files can in theory be recreated from them (unless an error is found that stops that), but it can take a very long time for a large backup that has the default sizes.

Depending on how many drives you have, you might lose the storage drive (and still have the databases), in which case you’re in good shape just recreating the storage drive from its backup (keeping in mind the advice others have given that best safety has an independent second backup instead of chained backup).

Losing the database drive will put you in the sometimes awkward situation of configuration and database reconstruction and Recreate. A direct restore from the backup files is probably faster than a full database Recreate, but you asked about continuing backups. You can also also consider the old one as an archive, then take a new one. That’s sometimes faster than rebuilding the database (lots of history in there) for old.

If your configuration changes a lot, or you like scripting, there’s a third-party client that can export backups.

Does it make sense to backup Duplicati config and db files? has some discussion, and there are others…

EDIT: You can move the database to the storage drive if you like, thus have a nice package for robocopy, however doing that might lose performance compared to a split-drive situation, or if storage drive is slow.