Gitlab pipeline docker build stage

Question

I'm trying to implement a docker build stage into my gitlab pipeline. Ideally I'd be able to build the image first and then run later stages against a container. However, when I use the build step in the gitlab-ci.yaml below I sometimes get the error:

error during connect: Get http://docker:2375/v1.37/info: dial tcp: lookup docker on 10.51.240.10:53: no such host ERROR: Job failed: error executing remote command: command terminated with non-zero exit code: Error executing in Docker Container: 1

On the occasions when it doesn't work I can only guess that the docker deamon isn't ready for connections. Does anyone have any ideas on how get this going?

gitlab-ci.yaml:

stages:
  - build

build:
  image: docker:18
  services:
    - docker:18-dind
  variables:
    DOCKER_DRIVER: overlay
    DOCKER_HOST: tcp://docker:2375/
  before_script:
    - docker info
  script:
    - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" "$CI_REGISTRY"
    - docker pull ${CI_REGISTRY_IMAGE}:latest || echo Could not fetch ${CI_REGISTRY_IMAGE}:latest from registry
    - docker pull ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG} || echo Could not fetch ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG} from registry
    - docker build -t ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG} --cache-from ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG} .
    - docker push ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG}
    - if [[ ${CI_COMMIT_REF_SLUG} == "master" ]] ; then docker tag ${CI_REGISTRY_IMAGE}:${CI_COMMIT_REF_SLUG} ${CI_REGISTRY_IMAGE}:latest ; fi
    - if [[ ${CI_COMMIT_REF_SLUG} == "master" ]] ; then docker push ${CI_REGISTRY_IMAGE}:latest ; fi
  stage: build

UPDATE: I am using a kubernetes executor.

Answer 1

Are you using gitlab-runner to run jobs? If so, are you setting --executor docker registering your runner?

Are you passing /var/run/docker.sock as a volume to the runner?

I have docker images building in GitLab CI working without any problems. I'm not passing any DOCKER_DRIVER or DOCKER_HOST variables.