Wiki / Backup and restore
What a backup is
| What it contains | The Kustos database -- one file per snapshot. Library-operations metadata backups are written alongside it, under backups\metadata\, one .yml per library; Kustos restores those itself from Library operations. |
| Where it lives | %ProgramData%\Kustos\backups\ on Windows, /config/backups in Docker |
| What it is called | kustos-20260930-155318.db — the date and time are UTC, not your local clock |
| How big | As big as your database. On a library of ~3,000 titles, about 700 MB each |
| How it is taken | SQLite's own VACUUM INTO, which is safe to run against a live database — Kustos does not have to stop, and the snapshot cannot be half-written |
What it does not contain. A backup is the database only:
- Not your artwork files. Those live in your assets folder and are untouched by a restore. That includes the clean pre-overlay posters in %ProgramData%\Kustos\overlay-base.
- Not your Plex library. Posters already pushed to Plex stay exactly as they are.
- Not Sonarr, Radarr or Prowlarr. Those are separate applications with their own backups.
So a backup holds every decision Kustos has made and nothing it has made those decisions about.
How many you have
Settings → Maintenance → Backups lists them, newest first, and the retention setting is a count, not a number of days. Fourteen backups is fourteen backups: if three are taken in one day, that day uses three of your fourteen. The panel shows the oldest date you can actually get back to, which is the question the count is a poor answer to.