Docker

Internal GitLab Docker Builds

Engineers construct software packages in isolation. Docker provides this execution environment. Continuous integration pipelines mandate standardized, reproducible container structures. You build Docker images on an authenticated internal GitLab runner using customized certificates.

Your GitLab runner configuration file requires a precise setup. The executor block demands the docker type. You must set the privileged attribute to true to allow Docker-in-Docker execution.

The .gitlab-ci.yml file outlines the process. It establishes the image, services, and variables. The script logs into the internal registry. It builds the container artifact from the local context. It attaches tags for the specific commit hash, the explicit semantic version, and the latest iteration. It pushes the artifacts to the registry.

image: docker:25.0.0

services:
  - name: my-internal-registry.internaldomain:5050/my-team/my-internal-dind-image:latest
    alias: docker
    entrypoint: ["env", "-u", "DOCKER_HOST"]
    command: ["dockerd-entrypoint.sh"]

variables:
  DOCKER_HOST: tcp://docker:2376
  DOCKER_TLS_CERTDIR: "/certs"

before_script:
  - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY

build:
  stage: build
  script:
    - VERSION_TAG=`cat VERSION`
    - docker build --tag $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA --tag $CI_REGISTRY_IMAGE:latest --tag $CI_REGISTRY_IMAGE:$VERSION_TAG .
    - docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
    - docker push $CI_REGISTRY_IMAGE:$VERSION_TAG
    - docker push $CI_REGISTRY_IMAGE:latest

This configuration protects proprietary code. It circumvents rate limits imposed by public registries. Custom runners grant comprehensive administrative authority over hardware resources and networking paths.