Dynamically add docker container ip in Dockerfile ( redis)

Question

How do I dynamically add container ip in other Dockerfile ( I am running two container a) Redis b) java application . I need to pass redis url on run time to my java arguments

Answer 1

you can assign a static ip address to your dokcer container when you run it, following the steps:

1 - create custom network:

docker network create --subnet=172.17.0.0/16 redis-net

2 - run the redis container to use the specified network, and assign the ip address:

docker run --net redis-net --ip 172.17.0.2 --name my-redis -d redis

by then you have the static ip address 172.17.0.2 for my-redis container, you don't need to inspect it anymore.

3 - now it is possible to run the java appication container but it must use the same network:

docker run --net redis-net my-java-app

of course you can optimize the solution, by using env variables or whatever you find convenient to your setup.

More infos can be found in the official docs (search for --ip):

• docker run
• docker network

Edit (add docker-compose):

I just find out that it is also possible to assign static ips using docker-compose, and this answer gives an example how.

This is a similar example just in case:

version: '3'

services:
  redis:
    container_name: redis
    image: redis:latest
    restart: always
    networks:
      vpcbr:
        ipv4_address: 172.17.0.2

  java-app:
    container_name: java-app
    build: 
    networks:
      vpcbr:
        ipv4_address: 172.17.0.3
    depends_on:
     - redis

networks:
  vpcbr:
    driver: bridge
    ipam:
     config:
       - subnet: 172.17.0.0/16
         gateway: 172.17.0.1

official docs: https://docs.docker.com/compose/networking/

hope this helps you find your way.