Jellyfin

Jellyfin creates backups through its API but can’t download or upload them, so mount Jellyfin’s backups folder into Backuparr. It is /config/data/backups in the official image and /config/data/data/backups in linuxserver’s:

    volumes:
      # official image, with Jellyfin's /config at /share/Container/jellyfin/config
      - /share/Container/jellyfin/config/data/backups:/mnt/jellyfin-backups
      # or linuxserver image, with Jellyfin's /config at /share/Container/jellyfin
      # - /share/Container/jellyfin/data/data/backups:/mnt/jellyfin-backups

Then fill in the card: the URL, an API key from Dashboard > API Keys (a user’s sign-in token can’t manage backups), and Backups folder = /mnt/jellyfin-backups. If the path is wrong, Test connection names the folder Jellyfin actually uses.

• What’s in the backup: Jellyfin’s database (users, watched state, playlists, collections, libraries, settings and API keys) and config files. Images and subtitles are left out; a library scan brings them back. The archive holds password hashes and API keys.
• Mount the folder read-write: Backuparr removes Jellyfin’s copy of each archive after taking it, and a restore writes into the folder. Read-only, backups still work but restores don’t.
• Restore replaces Jellyfin’s database and settings, then Jellyfin restarts to apply them. The archive stays in Jellyfin’s backups folder; delete it there when you’re done. API keys come back too: after rebuilding Jellyfin, enter the new install’s key under Restore to a different target, not in Settings - the key from the backup works again afterwards.
• Reverse proxy: Jellyfin takes its API key only in the Authorization header, so a proxy credential needs another header name.