Docker container unreachable from remote machine

Question

I use docker and docker-compose to deploy and run my java application running on port 5555.

I run it as docker-compose -f docker-compose.yml up -d

But if I run telnet command outside of my server where docker container is runnig I get Connection refused message. If run it inside the server everything is fine.

So these things are checked:

$: docker-compose ps

$: ufw status

Status: active

To                         Action      From
--                         ------      ----
OpenSSH                    ALLOW       Anywhere
5555/tcp                   ALLOW       Anywhere
5432                       ALLOW       Anywhere
OpenSSH (v6)               ALLOW       Anywhere (v6)
5555/tcp (v6)              ALLOW       Anywhere (v6)
5432 (v6)                  ALLOW       Anywhere (v6)

docker-compose.yml

version: '3'
services:
  db:
    container_name: db
    image: postgres
    restart: always
    ports:
      - 5432:5432

  auth:
    container_name: auth
    image: registryimg
    restart: always
    stdin_open: true
    tty: true
    ports:
      - 5555:5555

Dockerfile

FROM openjdk:8-jre
ADD target/auth.jar app.jar
EXPOSE 5555
ENTRYPOINT ["java", "-Djava.security.egd=file:/dev/./urandom", "-jar", "app.jar"]

Update 1

From the docker logs of my container I found that application binds correctly to desired port:

2019-01-18 10:18:11.481 DEBUG 1 --- [ntLoopGroup-2-1] io.netty.handler.logging.LoggingHandler  : [id: 0xaf27337e] REGISTERED
2019-01-18 10:18:11.485 DEBUG 1 --- [ntLoopGroup-2-1] io.netty.handler.logging.LoggingHandler  : [id: 0xaf27337e] BIND: localhost/127.0.0.1:5555
2019-01-18 10:18:11.489 DEBUG 1 --- [ntLoopGroup-2-1] io.netty.handler.logging.LoggingHandler  : [id: 0xaf27337e, L:/127.0.0.1:5555] ACTIVE

Update 2

From my home computer I run telnet command telnet myhost 5555 and I get an error:

Trying myhost...
telnet: Unable to connect to remote host: Connection refused

After it's done I watch my container logs and they are empty (netty didn't register any connections).

Else I want to point that if I telnet another container with potgresql inside it - everything is ok.

Answer 1

Well, shot answer is think what host you are binding.

In my case netty server was bound like this:

BIND: localhost/127.0.0.1:5555

I've change it to:

BIND: 0.0.0.0/0.0.0.0:5555

And it works like a charm!