Mailcow-dockerized: Question: Config with a containerized Reverse proxy

[jpbaril]

First, sorry to write here as it's a support request and not a real issue, but the forum is down.

I read https://mailcow.github.io/mailcow-dockerized-docs/firststeps-rp/ but it is not working.

I suspect the reason is that I run the reverse proxy in a container.

I'm new to Docker so a bit of help would be appreciated.

Thanks

P.S. I first searched many hours on the internet for a solution but could not find.

[chaosbunker]

I can't help, sorry. Just wanted to add that I am curious about this also 😊

[andryyy]

I wonder if it is enough to set network_mode: "host" and use Nginx' IP instead of hostname (DNS will likely fail to resolve) in the RP configuration.

[thaefner]

I have running nginx running in a docker container as proxy and it is working perfectly.
Make sure you have your proxy container added to the mailcowdockerized_mailcow-network network.
And your proxy-pass rule needs to be: proxy_pass http://nginx-mailcow:8080/;.
I think this is not mentioned in the docs.

[andryyy]

It is important that the external ips are given as x-headers to nginx-mailcow. @P0ly does docker-compose logs --tail=1000 nginx-mailcow show your external IP when accessing mailcow_hostname/rspamd ?

[thaefner]

@andryyy Oh, actually not. Does this affect spam filtering?
Have no issue with it otherwise.

[andryyy]

No. But you should disable the Rspamd web UI as everyone can login with any password.
Or you try to use network_mode host and proxy_pass to http://172.22.1.251:8080

[thaefner]

@andryyy Wow, good that I posted this here.
How can I disable the web UI?

[andryyy]

Should be enough to set static_dir = "/dev/null"; in data/conf/rspamd/override.d/worker-controller.inc.

[jpbaril]

I was almost able to make the reverse proxy to work.

I added mailcow-nginx to the reverse proxy network.

I wanted the mailcow webui to be in a directory, e.g. domain.com/mailcow

It kinda worked but all css, images, javascript and links were broken as they were refering to /css, /img, /js and not to /mailcow/css, etc.

Would there be any change possible to make that work?

[thaefner]

Got already asked in #393.
I think this is what you are looking for:
https://serverfault.com/questions/650117/serving-multiple-proxy-endpoints-under-location-in-nginx
Maybe you can try that out.

[PhoenixPeca]

It kinda worked but all css, images, javascript and links were broken as they were refering to /css, /img, /js and not to /mailcow/css, etc.

@jpbaril ill try to fix that up. For now, I suggest you to manually create a few redirect rules for these files.

[andryyy]

Maybe proxy_redirect is of use here.

[PhoenixPeca]

I'm thinking about linking the assets with relative urls without the leading foreslashes, so it wont break the RP out of the box. what do you think @andryyy?

[andryyy]

it could work, but I have no idea if it breaks the API. :/

[jpbaril]

Well, if that's too complicated I can also have it in a subdomain. That's what I did for now. Thanks all for your answers and for Mailcow.

BTW, I used Caddy as a very simple reverse proxy.

[andryyy]

It is important you setup Caddy as transparent proxy. Like...

proxy / 127.0.0.1:8080 {  
    transparent
}

[jpbaril]

Yeah, that's what I did except that instead of localhost I point to the Mailcow-nginx container's docker alias.
Thanks! ;-)

[Braintelligence]

@jpbaril
Can you post your complete working caddy config? :)

[jpbaril]

It's almost as andryyy posted and also based on domains listed in mailcow docs about reverse proxy:

mailcow.domain.com, mail.domain.com, autodiscover.domain.com, autoconfig.domain.com {
  proxy / mailcow:80 {
    transparent
  }
}

As the mailcow-nginx content is served by reverse proxy I changed the docker-compose file to not bind ports to the host and instead simply expose port 80.

```

ports:

- "${HTTPS_BIND:-0.0.0.0}:${HTTPS_PORT:-443}:${HTTPS_PORT:-443}"

- "${HTTP_BIND:-0.0.0.0}:${HTTP_PORT:-80}:${HTTP_PORT:-80}"

expose:

• 80
  ```