Parse /etc/hosts to allow using synonyms for IP addresses

[adrifromhh]

Is your feature request related to a problem? Please describe.
NPM seems to ignore the /etc/hosts file, so it's impossible to use a concise name for your proxy Hosts Forward Hostname / IP. That would be very helpful in a setup where the forward hosts are not docker containers, or on a different docker host.

Describe the solution you'd like
Please make NPM resolve addresses in the /etc/hosts file, so with the following addition to the Docker-Compose file, we could use synonyms for hosts IP addresses:

extra_hosts:
      - "host1:10.0.0.1"
      - "host2:10.0.0.2"

This adds hosts to the containers internal /etc/hosts file.

Best wishes
Adrian

[jc21]

In this project, Nginx is using a resolver directive which is generated on startup. It's usually something like this

resolver 127.0.0.11  valid=10s;

When doing this, Nginx ignores the hosts file for resolution.

From researching, I don't think there's any nginx-supported workaround for this. One possible option is to have the NPM project read from the hosts file on startup and create upstreams in nginx config, but that's a bit of a refactor.

[jc21]

I suppose another option is to disable the resolver generation with a env var. It might work for you

[jc21]

My commit message was Attempt to fix #5335 .. but github thought this means it's actually resolved.

If you'd like to test with the following image and env var:

services:
  npm:
    image: nginxproxymanager/nginx-proxy-manager-dev:develop
    environment:
      DISABLE_RESOLVER: true

let me know if that works for you

[adrifromhh]

Hey, thank you very much for your quick response! This would be exyctly what I need!
I pulled your image, but at the moment it still doesn't resolve, even though my host is present in the npm containers /etc/hosts file.

(Connection to the same host via it's IP works)

[srlihg66]

This requires DNS resolution.
Use a self-hosted DNS server to specify the IP address for resolution, and then set the DNS in docker-compose like this:

dns:

• 192.168.3.9 # your DNS server IP

This way, the domain can be resolved properly.