title: GitLab CI runner can't connect to unix:///var/run/docker.sock in kubernetes
body: <p>GitLab's running in kubernetes cluster. Runner can't build docker image with build artifacts. I've already tried several approaches to fix this, but no luck. Here are some configs snippets:</p>
  
  <p>.gitlab-ci.yml</p>
  
  <pre><code>image: docker:latest
  services:
    - docker:dind
  
  variables:
    DOCKER_DRIVER: overlay
  
  stages:
    - build
    - package
    - deploy
  
  maven-build:
    image: maven:3-jdk-8
    stage: build
    script: "mvn package -B --settings settings.xml"
    artifacts:
      paths:
        - target/*.jar
  
  docker-build:
    stage: package
    script:
    - docker build -t gitlab.my.com/group/app .
    - docker login -u gitlab-ci-token -p $CI_BUILD_TOKEN gitlab.my.com/group/app
    - docker push gitlab.my.com/group/app
  </code></pre>
  
  <p>config.toml</p>
  
  <pre><code>concurrent = 1
  check_interval = 0
  
  [[runners]]
    name = "app"
    url = "https://gitlab.my.com/ci"
    token = "xxxxxxxx"
    executor = "kubernetes"
    [runners.kubernetes]
      privileged = true
      disable_cache = true
  </code></pre>
  
  <p>Package stage log:</p>
  
  <pre><code>running with gitlab-ci-multi-runner 1.11.1 (a67a225)
    on app runner (6265c5)
  Using Kubernetes namespace: default
  Using Kubernetes executor with image docker:latest ...
  Waiting for pod default/runner-6265c5-project-4-concurrent-0h9lg9 to be running, status is Pending
  Waiting for pod default/runner-6265c5-project-4-concurrent-0h9lg9 to be running, status is Pending
  Running on runner-6265c5-project-4-concurrent-0h9lg9 via gitlab-runner-3748496643-k31tf...
  Cloning repository...
  Cloning into '/group/app'...
  Checking out 10d5a680 as master...
  Skipping Git submodules setup
  Downloading artifacts for maven-build (61)...
  Downloading artifacts from coordinator... ok        id=61 responseStatus=200 OK token=ciihgfd3W
  $ docker build -t gitlab.my.com/group/app .
  Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
  ERROR: Job failed: error executing remote command: command terminated with non-zero exit code: Error executing in Docker Container: 1
  </code></pre>
  
  <p>What am I doing wrong?</p>