How to sync files automatically with Syncthing

Syncthing is an open-source tool that keeps files synced between several devices, directly between them, with no cloud service in the middle. The data stays yours.

1. Install

apt-get update -y
apt-get install -y syncthing
systemctl enable --now syncthing@root

2. Access the interface

Syncthing has a web interface on port 8384. Access it through an SSH tunnel or a secured reverse proxy.

3. Connect the devices

Each device has a unique ID. You add them to each other and choose which folders sync. Changes propagate automatically in real time.

Uses

• Sync files between two servers for redundancy.
• Keep an identical working folder on several machines.
• Continuously back up from a device to the server.

Security

Syncthing traffic is encrypted. Do not expose the web interface publicly; use a reverse proxy with authentication or limit access with the firewall. For pure backup, a Backup Box with rsync stays simpler.