docker compose Custom Network Implementation Fixed Container ip Address

Because of the default bridge bridging network, the ip address changes when the container is restarted. In some scenarios, we want to fix the container IP address.
docker-compose is an orchestration tool for docker that creates networks, containers, etc. relative to command mode. Using configuration files is relatively more convenient and traceable to problems.

Paste docker-compose. yml files directly

version: '2'
services:
  nginx:
   image: nginx:1.13.12
   container_name: nginx
   restart: always
   tty: true
   networks:
     extnetwork:
      ipv4_address: 172.19.0.2
 
networks:
  extnetwork:
   ipam:
     config:
     - subnet: 172.19.0.0/16
      gateway: 172.19.0.1

Description:

gateway is the gateway address subnet is the network number segment extnetwork is a custom network name

Our nginx container in the above configuration fixed ip to 172.19. 0.2

Example, custom network mode:

version: '2'
services:
  nginx:
   image: nginx:1.13.12
   container_name: nginx
   restart: always
   networks:
     extnetwork:
   ports:
     - 80:80
   volumes:
     - '/nginx/conf.d:/etc/nginx/conf.d'
  nginx2:
   image: nginx:1.13.12
   container_name: nginx2
   restart: always
   networks:
     extnetwork:
      ipv4_address: 172.19.0.2
     
  db:
   image: mysql:5.7
   container_name: db
   volumes:
    - /var/lib/mysql:/var/lib/mysql
   restart: always
   networks:
     extnetwork:
   ports:
     - 3306:3306
   environment:
    MYSQL_ROOT_PASSWORD: wordpress
    MYSQL_DATABASE: wordpress
    MYSQL_USER: wordpress
    MYSQL_PASSWORD: wordpress   
  
  wordpress:
   image: wordpress:latest
   container_name: wordpress
   depends_on:
     - db
   ports:
     - "8000:80"
   restart: always
   networks:
     extnetwork:
   environment:
     WORDPRESS_DB_HOST: db:3306
     WORDPRESS_DB_NAME: wordpress
     WORDPRESS_DB_USER: wordpress
     WORDPRESS_DB_PASSWORD: wordpress
networks:
  extnetwork:
   ipam:
     config:
     - subnet: 172.19.0.0/16
      gateway: 172.19.0.1