无法连接到位于 tcp://localhost:2375/ 的 Docker 守护进程。是 docker 守护进程 运行。在 GitLab 上

Question

我正在尝试在 GitLab 中构建 CI 管道。我想问一下如何让 docker 在 GitLab CI.

中工作

来自本期：https://gitlab.com/gitlab-org/gitlab-runner/issues/4501#note_195033385

两种方式我都按照说明进行操作。使用 TLS 而未使用 TLS。 但它仍然卡住了。同样的错误

Cannot connect to the Docker daemon at tcp://localhost:2375/. Is the docker daemon running

我已尝试解决此问题。按照下面，

1. 启用 TLS

使用 .gitlab-ci.yml 和 config.toml 在 Runner 中启用 TLS。

这是我的 .gitlab-ci.yml:

image: docker:19.03
variables:
  DOCKER_HOST: tcp://localhost:2375/
  DOCKER_DRIVER: overlay2
  DOCKER_TLS_CERTDIR: "/certs"
  IMAGE_NAME: image_name

services:
  - docker:19.03-dind

stages:
  - build

publish:
  stage: build
  script:
    - docker build -t$IMAGE_NAME:$(echo $CI_COMMIT_SHA | cut -c1-10) .
    - docker push $IMAGE_NAME:$(echo $CI_COMMIT_SHA | cut -c1-10)
  only:
    - master   

这是我的 config.toml:

[[runners]]
  name = MY_RUNNER
  url = MY_HOST
  token = MY_TOKEN_RUNNER
  executor = "docker"
  [runners.custom_build_dir]
  [runners.docker]
    tls_verify = false
    image = "docker:stable"
    privileged = true
    disable_entrypoint_overwrite = false
    oom_kill_disable = false
    disable_cache = false
    volumes = ["/certs/client", "/cache"]                      
    shm_size = 0

2. 禁用 TLS

.gitlab-ci.yml:

image: docker:18.09
variables:
  DOCKER_HOST: tcp://localhost:2375/
  DOCKER_DRIVER: overlay2
  DOCKER_TLS_CERTDIR: ""
  IMAGE_NAME: image_name

services:
  - docker:18.09-dind

stages:
  - build

publish:
  stage: build
  script:
    - docker build -t$IMAGE_NAME:$(echo $CI_COMMIT_SHA | cut -c1-10) .
    - docker push $IMAGE_NAME:$(echo $CI_COMMIT_SHA | cut -c1-10)
  only:
    - master   

这是我的 config.toml:

[[runners]]
  environment = ["DOCKER_TLS_CERTDIR="]

有人知道吗？

解决方案

您可以在已接受的答案中看到。
此外，在我的例子中还有另一个。看起来根本原因来自 GitLab 托管的 Linux 服务器没有连接 Docker 的权限。让我们检查 GitLab 和服务器上 Docker 之间的权限连接。

Answer 1

您想将 DOCKER_HOST 设置为 tcp://docker:2375。它是一个 "service"，即 运行 在一个单独的容器中，默认情况下以图像名称命名，而不是本地主机。

这是一个应该有效的 .gitlab-ci.yml 片段：

# Build and push the Docker image off of merges to master; based off
# of Gitlab CI support in https://pythonspeed.com/products/pythoncontainer/
docker-build:
  stage: build

  image:
    # An alpine-based image with the `docker` CLI installed.
    name: docker:stable

  # This will run a Docker daemon in a container (Docker-In-Docker), which will
  # be available at thedockerhost:2375. If you make e.g. port 5000 public in Docker
  # (`docker run -p 5000:5000 yourimage`) it will be exposed at thedockerhost:5000.
  services:
   - name: docker:dind
     alias: thedockerhost

  variables:
    # Tell docker CLI how to talk to Docker daemon; see
    # https://docs.gitlab.com/ee/ci/docker/using_docker_build.html#use-docker-in-docker-executor
    DOCKER_HOST: tcp://thedockerhost:2375/
    # Use the overlayfs driver for improved performance:
    DOCKER_DRIVER: overlay2
    DOCKER_TLS_CERTDIR: ""

  script:
    # Download bash:
    - apk add --no-cache bash python3
    # GitLab has a built-in Docker image registry, whose parameters are set automatically.
    # See https://docs.gitlab.com/ee/ci/docker/using_docker_build.html#using-the-gitlab-contai
    #
    # CHANGEME: You can use some other Docker registry though by changing the
    # login and image name.
    - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" "$CI_REGISTRY"
    - docker build -t "$CI_REGISTRY_IMAGE" .
    - docker push "$CI_REGISTRY_IMAGE"

  # Only build off of master branch:
  only:
    - master

Answer 2

您可以尝试关闭tls

services:
- name: docker:dind
  entrypoint: ["dockerd-entrypoint.sh", "--tls=false"]
script:
- export DOCKER_HOST=tcp://127.0.0.1:2375 && docker build --pull -t ${CI_REGISTRY_IMAGE} .

因为有一个有趣的阅读https://gitlab.com/gitlab-org/gitlab-runner/-/issues/27300

docker:dind v20 sleeps for 16 seconds if you don't have TLS explicitly disabled, and that causes race condition where build container starts earlier than dockerd container