The latest docker:dind has breaking changes. Here are two fixes if you are enchanting issues with GitLab CI and your runners.
Fix 1: GitLab CI Config
Add the following to your .gitlab-ci.yml
variables: DOCKER_TLS_CERTDIR: ""
Fix 2: Change runner config
Alternatively, another fix is to change the runner:
$ nano /etc/gitlab-runner/config.toml
Modify to mach the following (specifically environment and volumes)
[[runners]] environment = ["DOCKER_DRIVER=overlay2","DOCKER_TLS_VERIFY=1","DOCKER_CERT_PATH=/certs/client"] [runners.docker] image = "docker:dind" privileged = true disable_entrypoint_overwrite = false oom_kill_disable = false disable_cache = false volumes = ["/cache","/certs"]
Then restart the gitlab runner
$ service gitlab-runner restart
I hope at least one of these fixes resolves your issues.