2.18. Starting Syncthing Automatically

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Jump to configuration for your system:

2.18.1. Windows

There is currently no official installer available for Windows. However, there are a number of easy solutions.

Task Scheduler

  1. Start the Task Scheduler (taskschd.msc)

  2. Create a New Task (“Action” menu -> “Create Task…”)

  3. General Tab:

    1. Name the task (for example ‘Syncthing’)

    2. Check “Run whether user is logged on or not”

  4. Triggers Tab:

    1. Click “New…”

    2. Set “Begin the task” to “At Startup”

    3. (optional) choose a delay

    4. Make sure Enabled is checked

    5. Click “OK”

  5. Actions Tab:

    1. Click “New…”

    2. [Action] should be set as “Start a program”

    3. Enter the path to syncthing.exe in “Program/Script”

    4. (optional) Enter “-no-console -no-browser” for “Add arguments (optional)”

    5. Click “OK”

  6. Settings Tab:

    1. (recommended) Keep the checkbox on “Allow task to be run on demand”

    2. Clear checkbox from “Stop task if it runs longer than:”

    3. (recommended) Keep “Do not start a new instance” for “If the task is already running, then the following rule applies”

  7. Click OK

  8. Enter password for the user.

Third-party Tools

There are a number of third-party utilities which aim to address this issue. These typically provide an installer, let Syncthing start automatically, and a more polished user experience (e.g. by behaving as a “proper” Windows application, rather than forcing you to start your browser to interact with Syncthing).

See also

Windows GUI Wrappers, Cross-platform GUI Wrappers.

Start on Login

Starting Syncthing on login, without a console window or browser opening on start, is relatively easy.

  1. Find the correct link of the Windows binary from the Syncthing website (choose amd64 if you have a 64-bit version of Windows)

  2. Extract the files in the folder (syncthing-windows-*) in the zip to the folder C:\syncthing

  3. Go to the C:\syncthing folder, make a file named syncthing.bat

  4. Right-click the file and choose Edit. The file should open in Notepad or your default text editor.

  5. Paste the following command into the file and save the changes: start "Syncthing" syncthing.exe -no-console -no-browser

  6. Right-click on syncthing.bat and press “Create Shortcut”

  7. Right-click the shortcut file syncthing.bat - Shortcut and click Copy

  8. Click Start, click All Programs, then click Startup. Right-click on Startup then click Open. Setup Screenshot

  9. Paste the shortcut (right-click in the folder and choose Paste, or press CTRL+V)

Syncthing will now automatically start the next time you open a new Windows session. No console or browser window will pop-up. Access the interface by browsing to http://localhost:8384/

If you prefer slower indexing but a more responsive system during scans, copy the following command instead of the command in step 5:

start "Syncthing" /low syncthing.exe -no-console -no-browser

Run as a service independent of user login

Warning

There are important security considerations with this approach. If you do not secure Syncthing’s GUI (and REST API), then any process running with any permissions can read/write any file on your filesystem, by opening a connection with Syncthing.

Therefore, you must ensure that you set a GUI password, or run Syncthing as an unprivileged user.

With the above configuration, Syncthing only starts when a user logs on to the machine. This is not optimal on servers where a machine can run long times after a reboot without anyone logged in. In this case it is best to create a service that runs as soon as Windows starts. This can be achieved using NSSM, the “Non-Sucking Service Manager”.

Note that starting Syncthing on login is the preferred approach for almost any end-user scenario. The only scenario where running Syncthing as a service makes sense is for (mostly) headless servers, administered by a sysadmin who knows enough to understand the security implications.

  1. Download and extract nssm to a folder where it can stay. The NSSM executable performs administration as well as executing as the Windows service so it will need to be kept in a suitable location.

  2. From an administrator Command Prompt, CD to the NSSM folder and run nssm.exe install <syncthing service name>

  3. Application Tab

    • Set Path to your syncthing.exe and enter -no-restart -no-browser -home="<path to your Syncthing folder>" as Arguments. Note: Logging is set later on. -logfile here will not be applied.

    • Windows NSSM Configuration Screenshot

  4. Details Tab

    • Optional: Set Startup type to Automatic (Delayed Start) to delay the start of Syncthing when the system first boots, to improve boot speed.

  5. Log On Tab

    • Enter the user account to run Syncthing as. This user needs to have full access to the Syncthing executable and its parent folder, configuration files / database folder and synced folders. You can leave this as Local System but doing so poses security risks. Setting this to your Windows user account will reduce this; ideally create a dedicated user account with minimal permissions.

  6. Process Tab

    • Optional: Change priority to Low if you want a more responsive system at the cost of somewhat longer sync time when the system is busy.

    • Optional: To enable logging enable “Console window”.

  7. Shutdown Tab

    • To ensure Syncthing is shut down gracefully select all of the checkboxes and set all Timeouts to 10000ms.

  8. Exit Actions Tab

    • Set Restart Action to Stop service (oneshot mode). Specific settings are used later for handling Syncthing exits, restarts and upgrades.

  9. I/O Tab

    • Optional: To enable logging set Output (stdout) to the file desired for logging. The Error field will be automatically set to the same file.

  10. File Rotation Tab

    • Optional: Set the rotation settings to your preferences.

  11. Click the Install Service Button

  12. To ensure that Syncthing exits, restarts and upgrades are handled correctly by the Windows service manager, some final settings are needed. Execute these in the same Command Prompt:

    • nssm set syncthing AppExit Default Exit

    • nssm set syncthing AppExit 0 Exit

    • nssm set syncthing AppExit 3 Restart

    • nssm set syncthing AppExit 4 Restart

  13. Start the service via sc start syncthing in the Command Prompt.

  14. Connect to the Syncthing UI, enable HTTPS, and set a secure username and password.

2.18.2. macOS

Using homebrew

  1. brew install syncthing

  2. Follow the information presented by brew to autostart Syncthing using launchctl.

Without homebrew

Download and extract Syncthing for Mac: https://github.com/syncthing/syncthing/releases/latest.

  1. Copy the syncthing binary (the file you would open to launch Syncthing) into a directory called bin in your home directory i.e. into /Users/<username>/bin. If “bin” does not exist, create it.

  2. Open syncthing.plist located in /etc/macosx-launchd. Replace the four occurrences of /Users/USERNAME with your actual home directory location.

  3. Copy the syncthing.plist file to ~/Library/LaunchAgents. If you have trouble finding this location select the “Go” menu in Finder and choose “Go to folder…” and then type ~/Library/LaunchAgents. Copying to ~/Library/LaunchAgents will require admin password in most cases.

  4. Log out and back in again. Or, if you do not want to log out, you can run this command in terminal: launchctl load ~/Library/LaunchAgents/syncthing.plist

Note: You probably want to turn off “Start Browser” in the web GUI settings to avoid it opening a browser window on each login. Then, to access the GUI type 127.0.0.1:8384 (by default) into Safari.

2.18.3. Linux

On any distribution (Arch, Debian, Linux Mint, Ubuntu, openSUSE)

  1. Launch the program ‘Startup Applications’.

  2. Click ‘Add’.

  3. Fill out the form:

    • Name: Syncthing

    • Command: /path/to/syncthing/binary -no-browser -home="/home/your\_user/.config/syncthing"

Using Supervisord

Add the following to your supervisor config file:

[program:syncthing]
command = /path/to/syncthing/binary -no-browser -home="/home/some_user/.config/syncthing"
directory = /home/some_user/
autorestart = True
user = some_user
environment = STNORESTART="1", HOME="/home/some_user"

The file is located at /etc/supervisor/supervisord.conf (Debian/Ubuntu) or /etc/supervisord.conf .

Using systemd

systemd is a suite of system management daemons, libraries, and utilities designed as a central management and configuration platform for the Linux computer operating system. It also offers users the ability to manage services under the user’s control with a per-user systemd instance, enabling users to start, stop, enable, and disable their own units. Service files for systemd are provided by Syncthing and can be found in etc/linux-systemd.

You have two primary options: You can set up Syncthing as a system service, or a user service.

Running Syncthing as a system service ensures that Syncthing is run at startup even if the Syncthing user has no active session. Since the system service keeps Syncthing running even without an active user session, it is intended to be used on a server.

Running Syncthing as a user service ensures that Syncthing only starts after the user has logged into the system (e.g., via the graphical login screen, or ssh). Thus, the user service is intended to be used on a (multiuser) desktop computer. It avoids unnecessarily running Syncthing instances.

Several distros (including Arch Linux) ship the needed service files with the Syncthing package. If your distro provides a systemd service file for Syncthing, you can skip step 2 when you setting up either the system service or the user service, as described below.

How to set up a system service

  1. Create the user who should run the service, or choose an existing one.

  2. Copy the Syncthing/etc/linux-systemd/system/syncthing@.service file into the load path of the system instance.

  3. Enable and start the service. Replace “myuser” with the actual Syncthing user after the @:

    systemctl enable syncthing@myuser.service
systemctl start syncthing@myuser.service

How to set up a user service

  1. Create the user who should run the service, or choose an existing one. Probably this will be your own user account.

  2. Copy the Syncthing/etc/linux-systemd/user/syncthing.service file into the load path of the user instance. To do this without root privileges you can just use this folder under your home directory: ~/.config/systemd/user/.

  3. Enable and start the service:

    systemctl --user enable syncthing.service
systemctl --user start syncthing.service

Checking the service status

To check if Syncthing runs properly you can use the status subcommand. To check the status of a system service:

systemctl status syncthing@myuser.service

To check the status of a user service:

systemctl --user status syncthing.service

Using the journal

Systemd logs everything into the journal, so you can easily access Syncthing log messages. In both of the following examples, -e tells the pager to jump to the very end, so that you see the most recent logs.

To see the logs for the system service:

journalctl -e -u syncthing@myuser.service

To see the logs for the user service:

journalctl -e --user-unit=syncthing.service

Permissions

If you enabled the Ignore Permissions option in the Syncthing client’s folder settings, then you will also need to add the line UMask=0002 (or any other umask setting <http://www.tech-faq.com/umask.html> you like) in the [Service] section of the syncthing@.service file.

Debugging

If you are asked on the bugtracker to start Syncthing with specific environment variables it will not work the normal way. Systemd isolates each service and it cannot access global environment variables. The solution is to add the variables to the service file instead.

To edit the system service, run:

systemctl edit syncthing@myuser.service

To edit the user service, run:

systemctl --user edit syncthing.service

This will create an additional configuration file automatically and you can define (or overwrite) further service parameters like e.g. Environment=STTRACE=model.