How to expose a container port outside of docker/container using docker-compose?

Question

I have a container that it has several ports, I want to have access to one of its ports (9001) outside of this docker as remote.

• My docker IP is: 172.17.0.1
• My container IP is: 172.19.0.23
• My server IP is: 192.168.1.131

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I have searched about that and I found expose port keyword, and I did it but not worked.

How to expose docker ports to make your containers externally accessible
Reference

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This is my docker-compose file:

version: '3'

services:
  nginx:
      image: nginx:latest
      container_name: nginx
      ports:
        - "8010:8010"

      volumes:
        - .:/code
        - ./nginx/default.conf:/etc/nginx/conf.d/default.conf

      links:
        - ivms

      restart: unless-stopped

  ivms:
      build: .
      container_name: ivms
      command: bash bashes/createDB.sh
      volumes:
        - .:/code
      expose:
        - "8010"
        - "9001"  # exposed disired port
      ports:
        - "9001:9001"

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I run above docker-compose file with: $ docker-compose up -d

• But when I using server_IP:9001 --> 192.168.1.131:9001 or docker_IP:9001 --> 172.17.0.1:9001 can not access to that (in remote or local mode)
• But when using container_IP:9001 --> 172.19.0.23:9001 this works in local.

What should I do that I can access to server_IP:9001 --> 192.168.1.131:9001?

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[NOTE]:

• In createDB.sh runs several operations such as creating a ZMQ on 9001 port.

• I have been set the port allowing before, using $ ufw allow 9001

• I tried on Ubuntu 16.04 and Ubuntu-Server 16.04

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Any help would be appreciated.

Answer 1

If you want to actually map the port you should use

ivms:
  build: .
  container_name: ivms
  command: bash bashes/createDB.sh
  volumes:
    - .:/code
  ports:
    - "8010:8010"
    - "9001:9001"  # now you can access them locally

warning you are using the same port for these two services ivms and nginx

The EXPOSE instruction informs Docker that the container listens on the specified network ports at runtime. You can specify whether the port listens on TCP or UDP, and the default is TCP if the protocol is not specified.

The EXPOSE instruction does not actually publish the port. It functions as a type of documentation between the person who builds the image and the person who runs the container, about which ports are intended to be published. -Docker Docs

Answer 2

Problem resolved with below instruction:

In ZMQ app (in ivms container) I had used from the server IP to binding a connection as follow:

import zmq

if __name__ == '__main__':
    context = zmq.Context()
    socket = context.socket(zmq.SUB)
    socket.setsockopt(zmq.SUBSCRIBE, "")
    socket.bind("tcp://192.168.1.131:9001")  # doesn't work with server or docker IP

    while True:
        data = socket.recv_json()

It was working only as below:

socket.bind("tcp://192.168.1.131:9001")  # works, but can't access as remote

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Now I edited this line as the follows:

socket.bind("tcp://*:9001")  # Works both locally and remotely.

---

And this is my docker-compose.yml configuration:

version: '3'

services:
  nginx:
      image: nginx:latest
      container_name: nginx
      ports:
        - "8010:8010"

      volumes:
        - .:/code
        - ./nginx/default.conf:/etc/nginx/conf.d/default.conf

      links:
        - ivms

      restart: unless-stopped

  ivms:
      build: .
      container_name: ivms
      command: bash bashes/createDB.sh
      volumes:
        - .:/code
      expose:
        - "8010"
      ports:
        - "9001:9001"