How to install gitlab-runner using docker-compose

First, choose a directory where the service will reside in. I recommend /opt/gitlab-runner.  Then create docker-compose.yml in said directory with this content:

services:
  gitlab-runner:
    image: 'gitlab/gitlab-runner:latest'
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - ./config:/etc/gitlab-runner
    restart: unless-stopped

then run this command to configure the runner:

docker-compose up -d
docker-compose exec gitlab-runner gitlab-runner register

It will ask you for details about the GitLab instance you want to attach to. You will find this information at https://<your-gitlab-domain>/admin/runners. This example is for my GitLab instance:

Runtime platform                                    arch=amd64 os=linux pid=38 revision=943fc252 version=13.7.0
Running in system-mode.

Enter the GitLab instance URL (for example, https://gitlab.com/):
https://gitlab.techoverflow.net/
Enter the registration token:
Loo2lahf9Shoogheiyae
Enter a description for the runner:
[148a53203df8]: My-Runner
Enter tags for the runner (comma-separated):

Registering runner... succeeded                     runner=oc-oKWMH
Enter an executor: custom, docker-ssh, shell, virtualbox, docker-ssh+machine, docker, parallels, ssh, docker+machine, kubernetes:
shell
Runner registered successfully. Feel free to start it, but if it's running already the config should be automatically reloaded!

Now, restart the runner that is running with the old config (i.e. with no gitlab instance being attached):

docker-compose down

After that’s finished, you can run the script from our previous post Create a systemd service for your docker-compose project in 10 seconds in the directory where docker-compose.yml is located.

curl -fsSL https://techoverflow.net/scripts/create-docker-compose-service.sh | sudo bash /dev/stdin

This will automatically generate a systemd service and start the runner (also on boot). For more details, see the corresponding blogpost. If your directory is named gitlab-runner, the service file will be stored in /etc/systemd/systemd/gitlab-runner.service, hence these are commands you can use to control the service:

Note that the script that creates the systemd service will automatically start the runner, so you don’t need to start it manually. !

Start by

sudo systemctl start gitlab-runner

Restart by

sudo systemctl restart gitlab-runner

Stop by

sudo systemctl stop gitlab-runner

View status:

sudo systemctl status gitlab-runner

View & follow logs:

sudo journalctl -xfu gitlab-runner

View logs in less:

sudo journalctl -xu gitlab-runner

Also see Mini systemd cheat-sheet

Also see How to register gitlab runner for multiple GitLab instances.

Note that you can also use

docker-compose logs -f

to view the logs (run this from the directory where docker-compose.yml) is located.

In case you see an error message like

error during connect: Post http://docker:2375/v1.40/auth: dial tcp: lookup docker on 192.168.178.1:53: no such host

in your jobs, see How to fix Gitlab CI error during connect: Post http://docker:2375/v1.40/auth: dial tcp: lookup docker on … no such host