1.通过docker network create 已经创建好了一个网络

ubuntu:ultimate是我自己提交的镜像，集成了一些常用的软件包。download.sh 中的内容是安装nginx，启动然后开始ping test3
后续的pin.sh pin1.sh pin2.sh分别是 ping nginx1、ping test1、ping test2，最后形成一个环。
通过networks指定使用的网络是 net111111，这是我自定义的网络

在下面与services对齐的位置配置自定义的网络
因为是事先建立好的，因此要用external:true
如果不指定名称，默认就是net111111，就是你在顶级networks下写的这个名字

当然，可以指定名称！下面两种yml文件，第一个是直接写为了net111111，第二个名称改为了net1，但其实使用的还是自定义的net111111网络

# 1
version: '3.7'
services:
  nginx_server:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: nginx1
    privileged: true
    entrypoint: [ "/app/download.sh" ]
    networks:
      - net111111
  test1:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test1
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net111111
    entrypoint: [ "/app/pin.sh" ]
  test2:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test2
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net111111
    entrypoint: [ "/app/pin1.sh" ]
  test3:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test3
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net111111
    entrypoint: [ "/app/pin2.sh" ]
networks:
  net111111:
    external: true

# 2
version: '3.7'
services:
  nginx_server:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: nginx1
    privileged: true
    entrypoint: [ "/app/download.sh" ]
    networks:
      - net1
  test1:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test1
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin.sh" ]
  test2:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test2
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin1.sh" ]
  test3:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test3
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin2.sh" ]
networks:
  net1:
    external: true
    name: net111111

2.在docker-compose.yml中配置网络

# 3
version: '3.7'
services:
  nginx_server:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: nginx2
    privileged: true
    entrypoint: [ "/app/download.sh" ]
    networks:
      - net1
  test1:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test11
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin.sh" ]
  test2:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test22
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin1.sh" ]
  test3:
    image: "ubuntu:ultimate"
    volumes:
      - "/app:/app"
    restart: always
    container_name: test33
    privileged: true
    depends_on:
      - nginx_server
    networks:
      - net1
    entrypoint: [ "/app/pin2.sh" ]
networks:
  net1:
    name: net222222
    driver: bridge
    ipam:
      driver: default
      config:
        - subnet: 172.16.200.0/24
          gateway: 172.16.200.1

创建成功了



通过容器名访问一下nginx

docker exec -it d711 w3m nginx2

成功！

参考
Networking in Compose
Compose file version 3 reference