[GitLab-CI] Docker lookup fails if DOCKER_HOST is set

[bluthej]

Description

I tried the minimal gitlab example but I could not get it to work with DOCKER_HOST: tcp://docker:2375/.

This sounded like #1269, but their fix was to set privileged = true, which was already set on my runner.

I eventually fixed it by not setting the DOCKER_HOST variable at all.

I didn't change the rest of the config, so I'm not sure if this is due to an update in the docker:dind service, but this might require updating the example. If necessary, I would be willing to perform additional tests if a better fix needs to be found.

Build log

No response

CI config

No response

[joerick]

My test over in #1996 contradicts this, unless I'm missing something. It gives:

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?