linuxserver/syncthing Docker Image

The https://linuxserver.io team brings you another container release featuring:

• regular and timely application updates
• easy user mappings (PGID, PUID)
• custom base image with s6 overlay
• weekly base OS updates with common layers across the entire LinuxServer.io ecosystem to minimise space usage, down time and bandwidth
• regular security updates

Find us at:

• https://blog.linuxserver.io - all the things you can do with our containers including How-To guides, opinions and much more!
• https://linuxserver.io/*** - realtime support / chat with the community and the team.
• https://github.com/orgs/linuxserver/discussions - post on our community forum.
• https://github.com/linuxserver - view the source for all of our repositories.
• https://opencollective.com/linuxserver - please *** helping us by either donating or contributing to our budget

https://github.com/linuxserver/docker-syncthing

Syncthing replaces proprietary sync and cloud services with something open, trustworthy and decentralized. Your data is your data alone and you deserve to choose where it is stored, if it is shared with some third party and how it's transmitted over the Internet.

Supported Architectures

We utilise the docker manifest for multi-platform awareness. More information is available from docker https://distribution.github.io/distribution/spec/manifest-v2-2/#manifest-list and our announcement https://blog.linuxserver.io/2019/02/21/the-lsio-pipeline-project/.

Simply pulling lscr.io/linuxserver/syncthing:latest should retrieve the correct image for your arch, but you can also pull specific arch images via tags.

The architectures supported by this image are:

Application Setup

**Note: ** The Syncthing devs highly suggest setting a password for this container as it listens on 0.0.0.0. To do this go to Actions -> Settings -> set user/password for the webUI.

Usage

To help you get started creating a container from this image you can either use docker-compose or the docker cli.

[!NOTE] Unless a parameter is flagged as 'optional', it is mandatory and a value must be provided.

docker-compose (recommended, https://docs.linuxserver.io/general/docker-compose)

yaml
---
services:
  syncthing:
    image: lscr.io/linuxserver/syncthing:latest
    container_name: syncthing
    hostname: syncthing #optional
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=Etc/UTC
    volumes:
      - /path/to/syncthing/config:/config
      - /path/to/data1:/data1
      - /path/to/data2:/data2
    ports:
      - 8384:8384
      - 22000:22000/tcp
      - 22000:22000/udp
      - 21027:21027/udp
    restart: unless-stopped

docker cli (https://docs.docker.com/engine/reference/commandline/cli/)

bash
docker run -d \
  --name=syncthing \
  --hostname=syncthing `#optional` \
  -e PUID=1000 \
  -e PGID=1000 \
  -e TZ=Etc/UTC \
  -p 8384:8384 \
  -p 22000:22000/tcp \
  -p 22000:22000/udp \
  -p 21027:21027/udp \
  -v /path/to/syncthing/config:/config \
  -v /path/to/data1:/data1 \
  -v /path/to/data2:/data2 \
  --restart unless-stopped \
  lscr.io/linuxserver/syncthing:latest

Parameters

Containers are configured using parameters passed at runtime (such as those above). These parameters are separated by a colon and indicate <external>:<internal> respectively. For example, -p 8080:80 would expose port 80 from inside the container to be accessible from the host's IP on port 8080 outside the container.

Environment variables from files (Docker secrets)

You can set any environment variable from a file by using a special prepend FILE__.

As an example:

bash
-e FILE__MYVAR=/run/secrets/mysecretvariable

Will set the environment variable MYVAR based on the contents of the /run/secrets/mysecretvariable file.

Umask for running applications

For all of our images we provide the ability to override the default umask settings for services started within the containers using the optional -e UMASK=022 setting. Keep in mind umask is not chmod it subtracts from permissions based on it's value it does not add. Please read up here before asking for support.

User / Group Identifiers

When using volumes (-v flags), permissions issues can arise between the host OS and the container, we avoid this issue by allowing you to specify the user PUID and group PGID.

Ensure any volume directories on the host are owned by the same user you specify and any permissions issues will vanish like magic.

In this instance PUID=1000 and PGID=1000, to find yours use id your_user as below:

bash
id your_user

Example output:

text
uid=1000(your_user) gid=1000(your_user) groups=1000(your_user)

Docker Mods

We publish various https://github.com/linuxserver/docker-mods to enable additional functionality within the containers. The list of Mods available for this image (if any) as well as universal mods that can be applied to any one of our images can be accessed via the dynamic badges above.

Support Info

• Shell access whilst the container is running:

  bash
  docker exec -it syncthing /bin/bash
  

• To monitor the logs of the container in realtime:

  bash
  docker logs -f syncthing
  

• Container version number:

  bash
  docker inspect -f '{{ index .Config.Labels "build_version" }}' syncthing
  

• Image version number:

  bash
  docker inspect -f '{{ index .Config.Labels "build_version" }}' lscr.io/linuxserver/syncthing:latest
  

Updating Info

Most of our images are static, versioned, and require an image update and container recreation to update the app inside. With some exceptions (noted in the relevant readme.md), we do not recommend or support updating apps inside the container. Please consult the Application Setup section above to see if it is recommended for the image.

Below are the instructions for updating containers:

Via Docker Compose

• Update images:

  • All images:

    bash
    docker-compose pull
    

  • Single image:

    bash
    docker-compose pull syncthing
    

• Update containers:

  • All containers:

    bash
    docker-compose up -d
    

  • Single container:

    bash
    docker-compose up -d syncthing
    

• You can also remove the old dangling images:

  bash
  docker image prune
  

Via Docker Run

• Update the image:

  bash
  docker pull lscr.io/linuxserver/syncthing:latest
  

• Stop the running container:

  bash
  docker stop syncthing
  

• Delete the container:

  bash
  docker rm syncthing
  

• Recreate a new container with the same docker run parameters as instructed above (if mapped correctly to a host folder, your /config folder and settings will be preserved)

• You can also remove the old dangling images:

  bash
  docker image prune
  

Image Update Notifications - Diun (Docker Image Update Notifier)

[!TIP] We recommend https://crazymax.dev/diun/ for update notifications. Other tools that automatically update containers unattended are not recommended or supported.

Building locally

If you want to make local modifications to these images for development purposes or just to customize the logic:

bash
git clone https://github.com/linuxserver/docker-syncthing.git
cd docker-syncthing
docker build \
  --no-cache \
  --pull \
  -t lscr.io/linuxserver/syncthing:latest .

The ARM variants can be built on x86_64 hardware and vice versa using lscr.io/linuxserver/qemu-static

bash
docker run --rm --privileged lscr.io/linuxserver/qemu-static --reset

Once registered you can define the dockerfile to use with -f Dockerfile.aarch64.

Versions

• 10.09.26: - Rebase to Alpine 3.24. Compile on Alpine edge.
• 03.03.26: - Rebase to Alpine 3.23.
• 16.08.25: - Rebase to Alpine 3.22.
• 13.08.25: - Use double-dash long options for syncthing v2.0.0.
• 03.12.24: - Rebase to Alpine 3.21.
• 06.06.24: - Rebase to Alpine 3.20.
• 05.03.24: - Rebase to Alpine 3.19.
• 05.09.23: - Rebase to Alpine 3.18.
• 01.07.23: - Deprecate armhf. As announced https://www.linuxserver.io/blog/a-farewell-to-arm-hf
• 13.02.23: - Rebase to Alpine 3.17, migrate to s6v3.
• 17.08.22: - Build on alpine 3.16 for go 1.18).
• 03.05.22: - Rebase to alpine 3.15 (builds on edge for go 1.18).
• 05.10.21: - Rebase to alpine 3.14.
• 12.05.21: - Remove sysctl parameter again
• 03.05.21: - Raise maximum UDP buffer size.
• 03.05.21: - Add port mapping for 22000/udp.
• 29.01.21: - Deprecate UMASK_SET in favor of UMASK in baseimage, see above for more information.
• 23.01.21: - Rebasing to alpine 3.13.
• 15.09.20: - Use go from alpine edge repo to compile. Remove duplicate UMASK env var. Add hostname setting.
• 01.06.20: - Rebasing to alpine 3.12.
• 19.12.19: - Rebasing to alpine 3.11.
• 28.06.19: - Rebasing to alpine 3.10.
• 23.03.19: - Switching to new Base images, shift to arm32v7 tag.
• 05.03.19: - Update Build process for v1.1.0 release.
• 22.02.19: - Rebasing to alpine 3.9.
• 16.01.19: - Add pipeline logic and multi arch.
• 30.07.18: - Rebase to alpine 3.8 and use buildstage.
• 13.12.17: - Rebase to alpine 3.7.
• 25.10.17: - Add env for manual setting of umask.
• 29.07.17: - Simplify build structure as symlinks failing on > 0.14.32
• 28.05.17: - Rebase to alpine 3.6.
• 08.02.17: - Rebase to alpine 3.5.
• 01.11.16: - Switch to compiling latest version from git source.
• 14.10.16: - Add version layer information.
• 30.09.16: - Fix umask.
• 09.09.16: - Add layer badges to README.
• 28.08.16: - Add badges to README.
• 11.08.16: - Rebase to alpine linux.
• 18.12.15: - Initial testing / release (IronicBadger)
• 24.09.15: - Inital dev complete (Lonix)