Deployed Docker-Compose returns "502 Bad Gateway"

Question

Please assist.

I found a blog post, https://blog.ssdnodes.com/blog/host-multiple-ssl-websites-docker-nginx/) regarding deploying multiple docker-compose application with the same nginx-proxy but with different VIRTUAL_HOST names

But for some reason, both applications are returning an Error 502 Bad Gateway

The following error is what I see when I run docker-compose logs nginx

2019/05/29 20:52:26 [error] 8#8: *15 connect() failed (111: Connection refused) while connecting to upstream, client: 52.209.30.187, server: gregsithole.com, request: "GET / HTTP/1.1", upstream: "http://172.20.0.5:80/", host: "gregsithole.com"

And I believe the upstream is using an internal docker network IP because that's not the IP for my Server. My upstream is determined by the following file: https://raw.githubusercontent.com/jwilder/nginx-proxy/master/nginx.tmpl

But I'm not too familiar with how it works.

The following is an example of my docker-compose files:

nginx-proxy/docker-compose.yaml

version: "3.6"
services:
  nginx:
    image: nginx
    container_name: nginx-proxy
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - conf:/etc/nginx/conf.d
      - vhost:/etc/nginx/vhost.d
      - html:/usr/share/nginx/html
      - certs:/etc/nginx/certs
    labels:
      - "com.github.jrcs.letsencrypt_nginx_proxy_companion.nginx_proxy=true"

  dockergen:
    image: jwilder/docker-gen
    container_name: nginx-proxy-gen
    restart: always
    depends_on:
      - nginx
    command: -notify-sighup nginx-proxy -watch -wait 5s:30s /etc/docker-gen/templates/nginx.tmpl /etc/nginx/conf.d/default.conf
    volumes:
      - conf:/etc/nginx/conf.d
      - vhost:/etc/nginx/vhost.d
      - html:/usr/share/nginx/html
      - certs:/etc/nginx/certs
      - /var/run/docker.sock:/tmp/docker.sock:ro
      - ./nginx.tmpl:/etc/docker-gen/templates/nginx.tmpl:ro

  letsencrypt:
    image: jrcs/letsencrypt-nginx-proxy-companion
    container_name: nginx-proxy-le
    restart: always
    depends_on:
      - nginx
      - dockergen
    environment:
      NGINX_PROXY_CONTAINER: nginx-proxy
      NGINX_DOCKER_GEN_CONTAINER: nginx-proxy-gen
    volumes:
      - conf:/etc/nginx/conf.d
      - vhost:/etc/nginx/vhost.d
      - html:/usr/share/nginx/html
      - certs:/etc/nginx/certs
      - /var/run/docker.sock:/var/run/docker.sock:ro

volumes:
  conf:
  vhost:
  html:
  certs:

networks:
  default:
    external:
      name: nginx-proxy

dockerized-ghost/docker-compose.yaml

version: "3.6"
services:

  ghost:
    image: ghost
    restart: always
    expose:
      - 80
    volumes:
      - ../../ghost:/var/lib/ghost/content
    environment:
      NODE_ENV: production
      url: https://blog.gregsithole.com
      VIRTUAL_HOST: blog.gregsithole.com
      LETSENCRYPT_HOST: blog.gregsithole.com
      LETSENCRYPT_EMAIL: hidden-email

networks:
  default:
    external:
      name: nginx-proxy

Please assist

Answer 1

You should assign the network nginx-proxy to the service ghost:

  ghost:
    networks:
      - nginx-proxy
    ...

Also assign the newtwork to nginx

  nginx:
    networks:
      - nginx-proxy
    ...

Also put the network configuration like this:

networks:
  nginx-proxy:
    external: true
  default:

And its all you need. Remember that in the docker compose file you have to declare the network as external, but that's not enough. You have also assign it individually to each service you want to be part of the network.

I recommend you to upgrade to Træfik or envoy. Nginx is limited in terms of scalability unless you pay for it.

Answer 2

After spending days on this issue trying various solutions. Updating my repo several times. I managed to fix it.

The blog article which I used was out of date as it was written back in 2017, and on the same blog I found the latest article, (https://blog.ssdnodes.com/blog/host-multiple-websites-docker-nginx/) which when checking the differences my nginx-proxy used nginx, 'jwilder/docker-gen' and jrcs/letsencrypt-nginx-proxy-companion.

The latest article only uses jwilder/nginx-proxy but I modified it to also include jrcs/letsencrypt-nginx-proxy-companion see my solution below:

version: "3.6"
services:
  nginx-proxy:
    image: jwilder/nginx-proxy
    container_name: nginx-proxy
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - conf:/etc/nginx/conf.d
      - vhost:/etc/nginx/vhost.d
      - html:/usr/share/nginx/html
      - dhparam:/etc/nginx/dhparam
      - certs:/etc/nginx/certs:ro
      - /var/run/docker.sock:/tmp/docker.sock:ro

  letsencrypt-nginx-proxy-companion:
    image: jrcs/letsencrypt-nginx-proxy-companion
    environment:
      NGINX_PROXY_CONTAINER: nginx-proxy
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - vhost:/etc/nginx/vhost.d
      - html:/usr/share/nginx/html
      - certs:/etc/nginx/certs

volumes:
  conf:
  vhost:
  html:
  dhparam:
  certs:

networks:
  default:
    external:
      name: nginx-proxy

Also, another one of my issues was that the port which the ghost uses on default was 2368 so I had to bind it to use port 80. So my solution for that was instead of exposing port 80 on ghost, I create an nginx Service which exposes port 80.

The following is my ghost setup:

version: "3.6"
services:

  ghost:
    image: ghost
    restart: always
    volumes:
      - ../../ghost:/var/lib/ghost/content
    environment:
      - VIRTUAL_HOST=blog.domain.com
      - LETSENCRYPT_HOST=blog.domain.com
      - LETSENCRYPT_EMAIL=name@domain.com
      - NODE_ENV=production
      - url=https://blog.domain.com

  nginx:
    image: nginx
    volumes:
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf:ro
    expose:
      - 80
    depends_on:
      - ghost
    links:
      - ghost

networks:
  default:
    external:
      name: nginx-proxy

So I was able to have both my website (https://gregsithole.com) & my blog (https://blog.gregsithole.com) work under the same proxy

Answer 3

I was able to use Greg's answer to resolve this problem, with one tweak: rather than add an nginx service to the ghost docker-compose.yml file, I added VIRTUAL_PORT=2368 and at long last things started right up for me.