Step‑by‑Step Guide to Install and Configure Syncthing for Master‑Slave Sync

Overview

Syncthing is a free, open‑source file‑synchronization tool that runs on Windows, macOS, Linux, Android, routers, Raspberry Pi and other hardware, offering a web‑based interface with Chinese language support.

Download

Obtain the installer from the official website https://syncthing.net/downloads/ and select the appropriate package for your platform.

Install Master Server

After extracting the archive, double‑click the executable to run it; the management page opens automatically, typically at http://127.0.0.1:8384/ and supports HTTPS connections.

Configure Master

Set the access address, username and password, then add a synchronization folder, customize its name and directory, and configure the sync interval. The system will automatically create a hidden .stfolder if needed.

Deploy Slave Server

Install Syncthing on the slave machine, then on the master UI click any device entry to reveal its device ID (e.g., NQIYOJG‑TNHCUH7‑44XX6D5‑452FZNU‑GODB7PH‑M5B3OTU‑QETJNOG‑TMVW3QZ) and copy it.

On the slave, add the master as a remote device using the copied ID.

The slave will show “not connected” until the master confirms the addition.

Configure Folder Sync

On the master, select the slave server (do not enable encryption) and save; the UI will show synchronization in progress.

On the slave, add the same folder.

Synchronization completes, showing master content in red and slave content in other colors, confirming bidirectional sync.

Sync Test

Testing confirms that synchronization is bidirectional, deletions and modifications propagate both ways, and the sync interval can be adjusted as needed. Log screenshots illustrate the process.