Preparation failed: Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock

Question

Trying to transform a project in gitlab to docker image. The gitlab is selfhosted. This is the error I get:

Running with gitlab-runner 13.12.0 (7a6612da)
on test -KnwQXuT
Preparing the "docker" executor
ERROR: Failed to remove network for build
ERROR: Preparation failed: Got permission denied while trying to connect to the Docker daemon 
socket at unix:///var/run/docker.sock: Get http://%2Fvar%2Frun%2Fdocker.sock/v1.25/info: dial 
unix /var/run/docker.sock: connect: permission denied (docker.go:858:0s)

I added a runner,registered it, created a gitlab-ci.yml with docker template which I left unmodified. As solutions I tried chmod 666 /var/run/docker.sock before and after adding the runner but it did not work. I also added sudo before running and registering the docker runner but still no success. I found another option to add my docker user to group docker but all my users are in the docker group. The docker runner is run as a docker image. I did not know what to do...Please help. I`m am trying for about 10 days with no success... Thanks in advance

Answer 1

1. Create docker group if not exist : sudo groupadd docker
2. Add user to docker group : sudo usermod -aG docker ${USER}
3. Change docker.sock to new permission : sudo chmod 666 /var/run/docker.sock
4. Finally restart docker daemon service : sudo systemctl restart docker

Answer 2

When you use gitlab self-hosted runner, by default, it creates a user named gitlab-runner . You need to assign the permissions to it.

sudo usermod -aG docker gitlab-runner

this will assign the correct permissions to the gitlab-runner and should pull the docker images on that VM.