0

I'm trying to work with VSCode Dev Containers, but I facing an issue.

I have a docker-compose.yml, with 2 services:

version: '3'

services:
  redis:
    image: redis:alpine
    ports:
      - "6379:6379"

  worker:
    depends_on:
      - redis
    image: app
    build: .
   ...

But if I try to run Dev Containers: Rebuild and Reopen, it fails to bring up the new redis container because the port 6379 is already in use: 0.0.0:6379 failed: port is already allocated

Then, to avoid this I manually run docker stop <container_id>. But I want to automate this , or put some command inside my docker-compose.yml to prevent this, is it possible?

How can I fix this issue?

Thanks

Vitor Albres
  • 113
  • 3
  • 9

1 Answers1

1

You're encountering the 'port is already in use' error because a port on your system can only be used by one process at a time, and Docker containers run in isolated environments, each with its own set of ports. To resolve this issue, you have a few options:

  1. Change Port Mapping: In your Docker Compose file (docker-compose.yml), you can modify the port mapping to use a different port on your host machine. For example, you can change the mapping from 6379:6379 to 8080:6379. This allows you to access the containerized service on port 8080 of your host machine.

  2. Use docker run with Port Binding: When starting a container using docker run, you can specify port binding using the -p or --publish option. For example: docker run -p 8080:6379 my_redis_container. This maps port 6379 in the container to port 8080 on your host.

  3. Use a Reverse Proxy: If you have multiple services that need to use the same port, consider using a reverse proxy like Nginx or Traefik. It can route requests to the appropriate containers based on hostname or path, allowing you to avoid port conflicts.

  4. Stop Existing Containers: You can manually stop the container that's using the conflicting port by running docker stop <container_id>. To automate this, you can create a script that stops the container before starting your development containers.

If you have any more questions or encounter any further issues, please feel free to ask. I'm here to help!

user21879527
  • 41
  • 4