Files and backups
Where an L4 Server stores messages and files, what a Backup contains and leaves out, and why backups live apart from live storage.
A Server keeps its data in its own storage. A Backup is a recovery copy kept somewhere else. It is not a second running Server.
Where data lives
| Data | On Cloudflare | On a VPS (celld) |
|---|---|---|
| Messages, Accounts, Roles, Tasks, Mail records, settings | The Server's D1 database | celld's D1, stored in the private RustFS bucket |
| Files and attachments, raw email | The Server's private R2 files bucket, or Basic KV storage | The same RustFS bucket |
| Live state (presence, typing, active calls) | Durable Objects | celld Durable Objects |
| Backups | A separate backups bucket, or a download | Archives outside the live volumes |
Every file read goes through the Server's normal authorization. Files are never served from a public bucket.
Basic KV storage on Cloudflare
A Cloudflare Server can run without R2. File payloads are then stored in the Server's existing KV namespace, with a limit of 20 MiB per file and 500 MiB in total. Cloudflare's own KV limits and daily quotas still apply.
To move to R2, open Server settings → Storage, choose Connect R2, then Move files to R2. The copy runs in resumable batches and checks every file's hash. Uploads pause while it runs; reading continues. The original KV copies are kept.
If a Server has no file storage at all, uploads and full backups fail with "File storage is unavailable. Ask the Server operator to configure storage."
What a Backup contains
The Server's own backup (Server settings → Deployment → Backups) is a TAR archive with:
- A logical export of the D1 database: messages, authentication records, Roles and all other Server data.
- The live files (R2 objects, or KV file payloads on Basic storage).
- A summary of table, row, object and byte counts.
It does not contain:
- Environment secrets, including
AUTH_SECRET. - Live Durable Object state.
- KV connection tickets.
- Data held by external providers, such as RealtimeKit.
Important
Keep the original
AUTH_SECRET(and any provider secrets) safe and separate from the archive. Stored credentials, such as model provider keys, backup keys and the Server's push notification identity, are encrypted with it. A restore with a different secret cannot decrypt them.
Where Backups go
On Cloudflare, the installer creates a separate backups bucket next to the files bucket. If it exists, the Server writes a backup there every week, and before every update. Without one, Settings downloads the archive to your computer. You can also save S3 credentials for a separate destination of your own; use a private bucket that is not the files bucket L4 already uses.
On a VPS, llll backup archives the whole installation, including .env and all volumes. On Docker Compose or Coolify you stop the stack and archive the volumes yourself. See VPS and Docker Compose.
Backups stay separate
- Backups are never stored in the live files bucket. Otherwise later archives could include earlier ones, and one bucket failure could remove both the files and their backups.
- Removing a Server never deletes its backup bucket or backup archives.
- Restoring a backup brings back the same Server UUID, Accounts, Roles, messages and files.
Updates make a verified backup first. See Releases and updates.