What is Syncthing ?

Syncthing is a peer-to-peer (P2P) file synchronization application.
It is designed to replace cloud-dependent synchronization services by offering a decentralized alternative. Your files are never stored on external servers: they only travel between your devices, ensuring better privacy.

Main features

  1. Real-time synchronization:
    Syncthing constantly monitors changes in synchronized folders and instantly replicates updates across connected devices.
  2. Open-source and free:
    Completely free, Syncthing is built on open-source code, allowing the community to audit and improve its security.
  3. Cross-platform:
    Compatible with Windows, macOS, Linux, Android, and even some embedded solutions such as NAS systems.
  4. Enhanced security:
    Syncthing uses the TLS protocol to encrypt communications and ensures that only authorized machines can exchange files.
  5. Conflict management:
    If simultaneous modifications are made on several devices, Syncthing creates backup versions to avoid any data loss.

Why choose Syncthing ?

  • Privacy:
    Unlike services such as Google Drive or Dropbox, your data never leaves your network or your devices.
  • Full control:
    You keep full control over your data and choose which folders to synchronize and which devices to authorize.
  • Flexibility:
    Ideal for individuals and small businesses looking for a reliable alternative with no recurring costs.
  • Performance:
    Syncthing is optimized to minimize bandwidth usage and provide fast performance.

Implementation

In this example, we will see how to use Syncthing on a private network, but first:
– Make sure both machines are connected to the same local network (LAN).
– Download and install Syncthing on both devices from the official website.

Step 2 : Installation

Launch Syncthing on both machines. The application usually runs in your browser through a local web interface.
Each device will generate a unique Device ID. You can copy it from Syncthing’s interface under “Actions” > “Show ID.”

Step 3 : Adding Devices

On Machine A :

  1. Click “Add Remote Device” in the Syncthing interface.
  2. Enter Machine B’s Device ID.
  3. Give the device a name (e.g., “Machine B”).
  4. If you are working on a local network, disable the “Global Discovery” option to avoid searching for the device on the interne

Repeat the same process on Machine B by adding Machine A’s Device ID.

Step 4: Creating and Sharing a Folder

On Machine A :

  1. Click “Add Folder.”
  2. Select a folder to synchronize.
  3. Assign a unique folder ID (example: shared_folder).
  4. Make sure to check the remote device (Machine B) in the list of shared devices.

On Machine B, a notification will appear to accept the shared folder. Click “Accept” and choose a local location for the folder.

Once the setup is complete, Syncthing will automatically start synchronizing files between both machines.
You can monitor synchronization status via the web interface.