> ## Documentation Index
> Fetch the complete documentation index at: https://3to1go.docs.thesteau.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> 3to1go is a self-hosted backup ecosystem made of two apps: Edge and Central.

<img src="https://mintcdn.com/3to1go/OsK8VqQyJUdPIZZK/images/3to1go.png?fit=max&auto=format&n=OsK8VqQyJUdPIZZK&q=85&s=e4e9f055ce6413548b7c3e9fdc6c0165" alt="Go gophers racing — 3, 2, 1, Go!" width="420" data-path="images/3to1go.png" />

3to1go is a simple, self-hosted backup system. It is one ecosystem made of **two separate apps** that you deploy independently:

<CardGroup cols={2}>
  <Card title="Edge" icon="laptop" href="/edge/overview">
    Runs on each machine that has files you care about. Finds the folders you marked, packs and **encrypts** them, and uploads them to Central on a schedule.
  </Card>

  <Card title="Central" icon="server" href="/central/overview">
    The always-on receiver. Stores encrypted snapshots on disk, keeps the most recent ones per job, and lets you browse and download them in a web UI.
  </Card>
</CardGroup>

Run one Central, and one Edge on every machine you want to back up. Each app has its own container, web UI, sign-in, and settings.

<Frame caption="Three example machines sending backups to one Central. You can add more Edges.">
  <img src="https://mintcdn.com/3to1go/bF_2U-Cls7u4cht_/images/backup-layout.svg?fit=max&auto=format&n=bF_2U-Cls7u4cht_&q=85&s=acdc0d93f1bcca7cc280cedef3c886db" alt="Three Edges with separate IP addresses on port 6556 upload to Central on port 6555, with an optional external sync to cloud storage for a third copy." width="960" height="410" data-path="images/backup-layout.svg" />
</Frame>

Each Edge keeps the original files on its machine; Central stores the second copy. An external sync tool can copy Central's encrypted snapshots to cloud storage for a **third copy**. You configure that extra copy separately. See [Storage and the 3-2-1 rule](/concepts/storage-and-3-2-1).

## The short version

<Steps>
  <Step title="Pick a machine to run Central">
    A home server, NAS, or VPS that stays on.
  </Step>

  <Step title="Run Edge on each machine you want to back up">
    Give each Edge a unique `EDGE_ID` and a credential minted by Central.
  </Step>

  <Step title="Mark folders with a .upload_dir file">
    Any folder containing `.upload_dir` becomes a backup job.
  </Step>

  <Step title="Edge packs and encrypts those folders">
    Snapshots are encrypted on Edge before they leave the machine.
  </Step>

  <Step title="Central stores the snapshots">
    Browse, download, and verify them from Central's web UI, or restore them from Edge.
  </Step>
</Steps>

## Why the name?

The name works on three levels: it references the [3-2-1 backup rule](https://en.wikipedia.org/wiki/Backup#Storage) (keep **3** copies, on **2** different media, with **1** offsite), it reads as a countdown (3, 2, 1, Go!), and the "Go" is the [Go](https://go.dev/) language both apps are written in.

## Why use 3to1go

* **Simple Central/Edge model.** Central receives and organizes backups. Each Edge owns scanning, encryption, scheduling, and upload retries.
* **Encrypted snapshots by default.** Edge encrypts archives before upload, so Central never needs access to your plaintext files.
* **Instance-aware storage.** Central tracks both `edge_id` and `edge_instance_id`, so related machines can be grouped without mixing their snapshots or pruning each other.
* **Operator-friendly credentials.** Central mints Edge credentials from its UI, and can revoke one without deleting any snapshots.
* **No giant config file.** You mark folders with a small file instead of writing a central backup manifest.

## Next steps

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/quickstart">
    Run Central and Edge with Docker and take your first backup.
  </Card>

  <Card title="How it works" icon="diagram-project" href="/concepts/how-it-works">
    Follow a folder from marker to stored snapshot.
  </Card>
</CardGroup>

<Note>
  3to1go is open source under the MIT License. Source, issues, and example deployments are on [GitHub](https://github.com/thesteau/3to1go).
</Note>