How to configure port mapping for replicated containers in Docker Compose? - docker

Question

The goal is to run two containers of publisher-app. One container should be mapped to port 8080 on the host machine, and the other on 8081. Here is the docker-compose:
publisher_app:
ports:
- "8080-8081:8080"
environment:
server.port: 8080
deploy:
mode: replicated
replicas: 2
Two containers are created, but as I understand, both ports are assigned to the first one, and the second one produces this error: Ports are not available: listen tcp 0.0.0.0:8081: bind: address already in use.
Here is the output of docker ps -a:
6c7067b4ebee spring-boot-rest-kafka_publisher_app "java -jar /app.jar" 33 seconds ago Up 28 seconds 0.0.0.0:8080->8080/tcp, 0.0.0.0:8081->8080/tcp spring-boot-rest-kafka_publisher_app_2
70828ba8f370 spring-boot-rest-kafka_publisher_app "java -jar /app.jar" 33 seconds ago Created spring-boot-rest-kafka_publisher_app_1
Docker engine version: 20.10.11
Docker compose version: 2.2.1
How to handle this case? Your help will be very appreciated.
Here is the source code: https://github.com/aleksei17/springboot-rest-kafka-mysql/blob/master/docker-compose.yml

Answer 1

tried locally on Windows 10 and failed similarly, both with v2 and with v2 disabled.
It seems like a compose issue
when tried on arch: amd64 fedora based linux distro with package manager installed docker and manually installing docker-compose 1.29.2 (using the official guide for linux) worked:
compose file:
version : "3"
services:
web:
image: "nginx:latest"
ports:
- "8000-8020:80"
docker command:
docker-compose up --scale web=5
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
b304d397b2cd nginx:latest "/docker-entrypoint.…" 14 seconds ago Up 7 seconds 0.0.0.0:8004->80/tcp, :::8004->80/tcp testdir_web_4
a8c6f177a6e6 nginx:latest "/docker-entrypoint.…" 14 seconds ago Up 7 seconds 0.0.0.0:8003->80/tcp, :::8003->80/tcp testdir_web_3
b1abe53e7d7d nginx:latest "/docker-entrypoint.…" 14 seconds ago Up 8 seconds 0.0.0.0:8002->80/tcp, :::8002->80/tcp testdir_web_2
ead91e9df671 nginx:latest "/docker-entrypoint.…" 14 seconds ago Up 9 seconds 0.0.0.0:8001->80/tcp, :::8001->80/tcp testdir_web_5
65ffd6a87715 nginx:latest "/docker-entrypoint.…" 24 seconds ago Up 21 seconds 0.0.0.0:8000->80/tcp, :::8000->80/tcp testdir_web_1