Provide static IP to docker containers via docker-compose

Question

I'm trying to provide static IP address to containers. I understand that I have to create a custom network. I create it and the bridge interface is up on the host machine (Ubuntu 16.x). The containers get IP from this subnet but not the static I provided.

Here is my docker-compose.yml:

version: '2'

services:
  mysql:
    container_name: mysql
    image: mysql:latest
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=root
    ports:
     - "3306:3306"
    networks:
     - vpcbr

  apigw-tomcat:
    container_name: apigw-tomcat
    build: tomcat/.
    ports:
     - "8080:8080"
     - "8009:8009"
    networks:
     - vpcbr
    depends_on:
     - mysql

networks:
  vpcbr:
    driver: bridge
    ipam:
     config:
       - subnet: 10.5.0.0/16
         gateway: 10.5.0.1
         aux_addresses:
          mysql: 10.5.0.5
          apigw-tomcat: 10.5.0.6

The containers get 10.5.0.2 and 10.5.0.3, instead of 5 and 6.

Answer 1

If you want to configure a default network in docker compose do it like that:

networks:
  default: # here we set the network name
    driver: bridge
    ipam:
      driver: default
      config:
      - subnet:  10.103.0.1/16

Answer 2

If you are never seeing the static IP address set, perhaps it could be because you are using "docker compose up". Try using "docker-compose up".

When I use "docker-compose up" (with the hyphen) I now see the static IPs assigned.

networks:
  hfnet:
    driver: bridge
    ipam:
      driver: default
      config:
        - subnet: 192.168.55.0/24
          gateway: 192.168.55.1

services:
  web:
    image: 'mycompany/webserver:latest'
    hostname: www
    domainname: mycompany.com
    stdin_open: true # docker run -i
    tty: true        # docker run -t
    networks:
      hfnet:
        ipv4_address: 192.168.55.10
    ports:
      - '80:80'
      - '443:443'
    volumes:
      - '../honeyfund:/var/www/html'

I wasted a lot of time to figure that one out. :(

Answer 3

I realized, that the more convenient and meaningful way is to give the container a container-name. You can use the name in the same docker network as source. This helped me because the docker-containers had changing IPs and by this I can communicate with another container with a static name that I can use in config-files.

Answer 4

I was facing some difficulties with an environment variable that is with custom name (not with container name /port convention for KAPACITOR_BASE_URL and KAPACITOR_ALERTS_ENDPOINT). If we give service name in this case it wouldn't resolve the ip as

KAPACITOR_BASE_URL:  http://kapacitor:9092

In above http://[**kapacitor**]:9092 would not resolve to http://172.20.0.2:9092

I resolved the static IPs issues using subnetting configurations.

version: "3.3"

networks:
  frontend:
    ipam:
      config:
        - subnet: 172.20.0.0/24
services:
    db:
        image: postgres:9.4.4
        networks:
            frontend:
                ipv4_address: 172.20.0.5
        ports:
            - "5432:5432"
        volumes:
            - postgres_data:/var/lib/postgresql/data

    redis:
        image: redis:latest
        networks:
            frontend:
                ipv4_address: 172.20.0.6
        ports:
            - "6379"

    influxdb:
        image: influxdb:latest
        ports:
            - "8086:8086"
            - "8083:8083"
        volumes:
            - ../influxdb/influxdb.conf:/etc/influxdb/influxdb.conf
            - ../influxdb/inxdb:/var/lib/influxdb
        networks:
            frontend:
                ipv4_address: 172.20.0.4
        environment:
          INFLUXDB_HTTP_AUTH_ENABLED: "false"
          INFLUXDB_ADMIN_ENABLED: "true"
          INFLUXDB_USERNAME: "db_username"
          INFLUXDB_PASSWORD: "12345678"
          INFLUXDB_DB: db_customers

    kapacitor:
        image: kapacitor:latest
        ports: 
            - "9092:9092"
        networks:
            frontend:
                ipv4_address: 172.20.0.2
        depends_on:
            - influxdb
        volumes:
            - ../kapacitor/kapacitor.conf:/etc/kapacitor/kapacitor.conf
            - ../kapacitor/kapdb:/var/lib/kapacitor
        environment:
          KAPACITOR_INFLUXDB_0_URLS_0: http://influxdb:8086

    web:
        build: .
        environment:
          RAILS_ENV: $RAILS_ENV
        command: bundle exec rails s -b 0.0.0.0
        ports:
            - "3000:3000"
        networks:
            frontend:
                ipv4_address: 172.20.0.3
        links:
            - db
            - kapacitor
        depends_on:
            - db
        volumes:
            - .:/var/app/current
        environment:
          DATABASE_URL: postgres://postgres@db
          DATABASE_USERNAME: postgres
          DATABASE_PASSWORD: postgres
          INFLUX_URL: http://influxdb:8086
          INFLUX_USER: db_username
          INFLUX_PWD: 12345678
          KAPACITOR_BASE_URL:  http://172.20.0.2:9092
          KAPACITOR_ALERTS_ENDPOINT: http://172.20.0.3:3000

volumes:
  postgres_data:

Answer 5

Note that I don't recommend a fixed IP for containers in Docker unless you're doing something that allows routing from outside to the inside of your container network (e.g. macvlan). DNS is already there for service discovery inside of the container network and supports container scaling. And outside the container network, you should use exposed ports on the host. With that disclaimer, here's the compose file you want:

version: '2'

services:
  mysql:
    container_name: mysql
    image: mysql:latest
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=root
    ports:
     - "3306:3306"
    networks:
      vpcbr:
        ipv4_address: 10.5.0.5

  apigw-tomcat:
    container_name: apigw-tomcat
    build: tomcat/.
    ports:
     - "8080:8080"
     - "8009:8009"
    networks:
      vpcbr:
        ipv4_address: 10.5.0.6
    depends_on:
     - mysql

networks:
  vpcbr:
    driver: bridge
    ipam:
     config:
       - subnet: 10.5.0.0/16
         gateway: 10.5.0.1