The simple way to run Docker-in-Docker for CI

FROM jenkins/jenkins:lts

USER root 

COPY docker_install.sh /docker_install.sh

RUN chmod +x /docker_install.sh

RUN /docker_install.sh

#!/bin/sh

apt-get update && \
apt-get -y install apt-transport-https \
     ca-certificates \
     curl \
     gnupg2 \
     zip \
     unzip \
     software-properties-common && \
curl -fsSL https://download.docker.com/linux/$(. /etc/os-release; echo "$ID")/gpg > /tmp/dkey; apt-key add /tmp/dkey && \
add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/$(. /etc/os-release; echo "$ID") \
   $(lsb_release -cs) \
   stable" && \
apt-get update && \
apt-get -y install docker-ce

version: '3'

services:
  jenkins:
    build:
      context: .
      dockerfile: Dockerfile
    container_name: 'jenkins'
    restart: always
    ports:
      - '8081:8080'
      - '50200:50000'
    expose:
      - '8080'
      - '50000'
    volumes:
      - 'jenkins_data:/var/jenkins_home'
      - '/var/run/docker.sock:/var/run/docker.sock'
    environment:
      TZ: "Asia/Seoul"

    networks:
      - jenkins

volumes:
  jenkins_data:

networks:
  jenkins:

docker compose up --file docker-compose-jenkins.yaml --detach --project-name="jenkins"

docker exec -it jenkins bash
root@c83639ffd83c:/# docker ps
CONTAINER ID   IMAGE                  COMMAND                  CREATED              STATUS              PORTS                                                                            NAMES
c83639ffd83c   jenkins_jenkins        "/sbin/tini -- /usr/…"   About a minute ago   Up About a minute   0.0.0.0:8081->8080/tcp, 0.0.0.0:50200->50000/tcp                                 jenkins