[SOLVED] Docker [Compose] configuring Iptables wrong

Issue

I am trying to setup this project: https://github.com/ao-data/albiondata-docker

But my server does not allow me to connect to any hosts from my browser.

this is the Docker-Compose stripped down:

version: "3"
services:
  sql:
    depends_on: 
      - mysql
      - nats
    networks: 
      - albiondata
  api:
    ports:
      - 8056:80
    depends_on: 
      - mysql
    networks: 
      - albiondata
  gate:
    ports:
      - 4223:4223
    depends_on: 
      - nats
      - redis
    networks: 
      - albiondata
  deduper:
    depends_on: 
      - nats
      - redis
    networks: 
      - albiondata
  nats:
    ports:
      - 4222:4222
      - 6222:6222
      - 8222:8222
    networks: 
      - albiondata
  mysql:
    ports:
      - 3306:3306
    networks: 
      - albiondata
  mysql-backup:
    depends_on: 
      - mysql
    networks: 
    - albiondata
  redis:
    ports:
      - 6379:6379
    networks: 
      - albiondata
  proxy:
    ports:
      - "80:80"
      - "443:443"
      - "81:81"
    networks: 
      - albiondata
  nginx:
    ports:
      - "80:80"
      - "443:443"
      - "81:81"
    networks: 
      - albiondata
  nginx:
    ports:
      - 8080:80        
networks:
  albiondata:

I am using ufw for configuration of iptables and i've also enabled forwarding described here https://docs.docker.com/network/bridge/ with the commands

sysctl net.ipv4.conf.all.forwarding=1
sudo iptables -P FORWARD ACCEPT

I have validated my ports with netstat (yes they are open to 0.0.0.0) and all containers are running with no error. I have also allowed all ports specified in the docker-compose specifically with ufw aswell.

But I cannot connect to port 8080 or 4223, the api bound to port 8056 is also not available. Disabling iptables (deleting all rules) fixes it and I can access all services.

My server is running on debian 11

Solution

When you work with ufw, and make change in firewall, you should restart docker daemon.

Both docker daemon and ufw work with iptable in background. When you make any change in ufw, it conflicts with docker daemon.

Restart it with: docker restart docker

Answered By - Mojtaba Ahadi

Answer Checked By - Gilberto Lyons (WPSolving Admin)