imagegenius/semaphore

Semaphore is a modern UI for Ansible. It lets you easily run Ansible playbooks, get notifications about fails, control access to deployment system.

Supported Architectures

We use Docker manifest for cross-platform compatibility. More details can be found on Docker's website.

To obtain the appropriate image for your architecture, simply pull ghcr.io/imagegenius/semaphore:latest. Alternatively, you can also obtain specific architecture images by using tags.

This image supports the following architectures:

Architecture	Available	Tag
x86-64	✅	amd64-<version tag>
arm64	✅	arm64v8-<version tag>
armhf	❌

Application Setup

The WebUI can be accessed at http://your-ip:3000, login with the admin user/password set in the variables.

The home for Semaphore (abc) is set to /config, so that SSH keys can be stored in /config/.ssh.

To get SSH working, you first need to SSH into the client (with keys of course). Add your key to /config/.ssh/id_rsa, make sure that you run chmod 600 id_rsa and chown abc:abc id_rsa.

You can now run s6-setuidgid abc /bin/bash to open a shell as abc, and run your SSH commands (ssh <user>@<host>), and you should be prompted with yes/no, type yes, then exit the SSH session, Semaphore/Ansible should now be able to SSH into that client.

Usage

Example snippets to start creating a container:

Docker Compose

---
services:
  semaphore:
    image: ghcr.io/imagegenius/semaphore:latest
    container_name: semaphore
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=Etc/UTC
      - SEMAPHORE_DB_DIALECT=bolt
      - SEMAPHORE_ADMIN=admin
      - SEMAPHORE_ADMIN_PASSWORD=password
      - "SEMAPHORE_ADMIN_NAME=John Doe"
      - [email protected]
      - SEMAPHORE_ACCESS_KEY_ENCRYPTION=admin
      - SEMAPHORE_DB_HOST=192.168.1.x #optional
      - SEMAPHORE_DB_USER=semaphore #optional
      - SEMAPHORE_DB_PASS=semaphore #optional
      - SEMAPHORE_DB=semaphore #optional
    volumes:
      - </path/to/appdata>:/config
    ports:
      - 3000:3000
    restart: unless-stopped

Docker CLI (Click here for more info)

docker run -d \
  --name=semaphore \
  -e PUID=1000 \
  -e PGID=1000 \
  -e TZ=Etc/UTC \
  -e SEMAPHORE_DB_DIALECT=bolt \
  -e SEMAPHORE_ADMIN=admin \
  -e SEMAPHORE_ADMIN_PASSWORD=password \
  -e SEMAPHORE_ADMIN_NAME="John Doe" \
  -e [email protected] \
  -e SEMAPHORE_ACCESS_KEY_ENCRYPTION=admin \
  -e SEMAPHORE_DB_HOST=192.168.1.x `#optional` \
  -e SEMAPHORE_DB_USER=semaphore `#optional` \
  -e SEMAPHORE_DB_PASS=semaphore `#optional` \
  -e SEMAPHORE_DB=semaphore `#optional` \
  -p 3000:3000 \
  -v </path/to/appdata>:/config \
  --restart unless-stopped \
  ghcr.io/imagegenius/semaphore:latest

Parameters

To configure the container, pass variables at runtime using the format <external>:<internal>. For instance, -p 8080:80 exposes port 80 inside the container, making it accessible outside the container via the host's IP on port 8080.

Parameter	Function
-p 3000	WebUI Port
-e PUID=1000	UID for permissions - see below for explanation
-e PGID=1000	GID for permissions - see below for explanation
-e TZ=Etc/UTC	Specify a timezone to use, see this list.
-e SEMAPHORE_DB_DIALECT=bolt	Choose either bolt, postgres or mysql. If bolt is chosen, the optional variables (SEMAPHORE_DB...) do not need to be specified as bolt is a 'built-in' database
-e SEMAPHORE_ADMIN=admin	Specify the admin user
-e SEMAPHORE_ADMIN_PASSWORD=password	Specify the admin password
-e SEMAPHORE_ADMIN_NAME=John Doe	Specify the admin name
-e [email protected]	Specify the admin email
-e SEMAPHORE_ACCESS_KEY_ENCRYPTION=admin	Specify the key for encrypting access keys in database. It must be generated by using the following command: `head -c32 /dev/urandom
-e SEMAPHORE_DB_HOST=192.168.1.x	Host IP of PostgreSQL or MySQL
-e SEMAPHORE_DB_USER=semaphore	PostgreSQL/MySQL database user
-e SEMAPHORE_DB_PASS=semaphore	PostgreSQL/MySQL database password
-e SEMAPHORE_DB=semaphore	PostgreSQL/MySQL database
-v /config	Appdata Path

Umask for running applications

All of our images allow overriding the default umask setting for services started within the containers using the optional -e UMASK=022 option. Note that umask works differently than chmod and subtracts permissions based on its value, not adding. For more information, please refer to the Wikipedia article on umask here.

User / Group Identifiers

To avoid permissions issues when using volumes (-v flags) between the host OS and the container, you can specify the user (PUID) and group (PGID). Make sure that the volume directories on the host are owned by the same user you specify, and the issues will disappear.

Example: PUID=1000 and PGID=1000. To find your PUID and PGID, run id user.

  $ id username
    uid=1000(dockeruser) gid=1000(dockergroup) groups=1000(dockergroup)

Updating the Container

Most of our images are static, versioned, and require an image update and container recreation to update the app. We do not recommend or support updating apps inside the container. Check the Application Setup section for recommendations for the specific image.

Instructions for updating containers:

Via Docker Compose

• Update all images: docker-compose pull
  • or update a single image: docker-compose pull semaphore
• Let compose update all containers as necessary: docker-compose up -d
  • or update a single container: docker-compose up -d semaphore
• You can also remove the old dangling images: docker image prune

Via Docker Run

• Update the image: docker pull ghcr.io/imagegenius/semaphore:latest
• Stop the running container: docker stop semaphore
• Delete the container: docker rm semaphore
• 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: docker image prune

Versions

• 24.04.24: - rebase to alpine 3.19
• 28.04.23: - Added rsync package.
• 14.04.23: - Initial release.