Trouble connecting to Docker daemon in GitLab CI-CodePudding

I'm trying to create a fairly simple GitLab CI file to build out Docker images. Whenever I run the pipeline, I end up getting a Docker daemon connection issue. What can I do to properly build my image? Thanks!

GitLab CI:

image: docker:20.10.16

services:
  - docker:20.10.16-dind

variables:
  DOCKER_HOST: tcp://docker:2375

iac-build:
  stage: build
  extends: .iac
  rules:
    - if: $CI_COMMIT_BRANCH != $CI_DEFAULT_BRANCH
      when: always
    - if: $CI_PIPELINE_SOURCE == 'merge_request_event'
      when: never
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
      when: always
  script:
    - docker build -t testfirstimage .
  allow_failure: false

Error:

$ docker build -t testfirstimage .
failed to dial gRPC: cannot connect to the Docker daemon. Is 'docker daemon' running on this host?: dial tcp 127.0.0.1:2375: connect: connection refused
Cleaning up project directory and file based variables
ERROR: Job failed: command terminated with exit code 1

CodePudding user response：

First thing I would check is if you already have something running on that local host - I've literally tried running a server on a local host port for hours and kept having it refused, only to find out that I had forgotten to terminate my connection to that port.
If that isn't the issue, I had this issue before and had to run this command to get it to work:


concurrent = 1
check_interval = 0

[[runners]]
  name = "#####"
  url = "#####"
  token = "#####"
  executor = "docker"
  [runners.docker]
    tls_verify = false
    image = "docker:latest"
    privileged = false
    disable_cache = false
    cache_dir = "cache"
    volumes = ["/var/run/docker.sock:/var/run/docker.sock", "/cache"]
  [runners.cache]
    Insecure = false

I spent forever trying to figure it out and couldn't get anything to work until I found out to add

volumes = ["/var/run/docker.sock:/var/run/docker.sock", "/cache"]

I didn't figure it out by magic though - props to this issues page: https://gitlab.com/gitlab-org/gitlab-runner/-/issues/1986

Hopefully that works.

CodePudding user response：

In order to get Docker-in-Docker working with GitLab CI, you will first need to decide if you want to use Docker-in-Docker with or without TLS. Then, change /etc/gitlab-runner/config.toml settings, and assign the DOCKER_TLS_CERTDIR in your .gitlab-ci.yml file. See the Docker-in-docker section of the GitLab docs.

Docker-in-docker with TLS:

# /etc/gitlab-runner/config.toml

[[runners]]
  url = "https://gitlab.com/"
  token = TOKEN
  executor = "docker"
  [runners.docker]
    tls_verify = false
    image = "docker:20.10.16"
    privileged = true
    disable_cache = false
    volumes = ["/certs/client", "/cache"]
  [runners.cache]
    [runners.cache.s3]
    [runners.cache.gcs]

# .gitlab-ci.yml

image: docker:20.10.16

variables:
  DOCKER_TLS_CERTDIR: "/certs"

services:
  - docker:20.10.16-dind

before_script:
  - docker info

# rest of .gitlab-ci.yml