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dockernetwork-programmingproxyconsul

docker reverse proxy DNS/networking issues

I'll try to explain and draw this out

What I want to achieve:

Diagram

Sorry for the crappy paint diagram. Right now, it works perfectly if I hit it from the 10.10.10.0 network. The problem is DNS resolves jenkins.network.com to the 10.10.10.0 network. I want to go back through the proxy though as that has SSL termination to get to the sonarqube server. Is there a good way to accomplish this to keep the services behind the proxy? Do I need to create a second DNS server with the docker network on it? Is this possible to do with consul to have both the external and internal services point to the same domain name?

Edit: Doing something like this would work, since everything goes through the proxies. So when jenkins hits sonar, it think's its ip really is 10.10.10.51 and it can hit it through there. enter image description here

What I need it to do: enter image description here I need it to go out of the proxy, then come back in through the proxy. IE:

172.16.10.2 ---- 172.16.10.1 ----- 10.10.10.50 ----- Proxy then takes over to route to proper location (172.16.10.3:8080 or something)

Solution

  • Since you didn't post your compose. I am making few assumptions. The compose assumed is below

    version: '3'

services:
  nginx:
    image: nginx
    ports:
      - 80:80
      - 443:443
    depends_on:
      - jenkins
      - sonar
  jenkins:
    image: jenkins
  sonar:
    image: sonarqube

    And all of these run on 10.10.10.50. Now if you set the DNS to 10.10.10.20 inside and outside, both jenkins.network.com will resolve to 10.10.10.50. But inside the docker network you want jenkins.network.com to resolved to the IP of the container.

    So if all above is correct then below is the simplest solution

    version: '3'

service:
  nginx:
    image: nginx
    ports:
      - 80:80
      - 443:443
    depends_on:
      - jenkins
      - sonar
  jenkins:
    image: jenkins
    networks:
      default:
        aliases:
          - jenkins.network.com
  sonar:
    image: sonar
    networks:
      default:
        aliases:
          - sonar.network.com

    On the nginx image i can reach jenkins.network.com

    root@be6492f18851:/# telnet jenkins.network.com 8080
Trying 172.23.0.3...
Connected to jenkins.network.com.
Escape character is '^]'.
Connection closed by foreign host.

    And you can do that from both jenkins and sonar containers and get the same results

    Edit-1

    If you want the DNS to go through proxy, you can change the aliases to that network

    version: '3'

service:
  nginx:
    image: nginx
    ports:
      - 80:80
      - 443:443
    depends_on:
      - jenkins
      - sonar
    networks:
      default:
        aliases:
          - sonar.network.com
          - jenkins.network.com
  jenkins:
    image: jenkins
  sonar:
    image: sonar