Check_MK and Apache Reverse Proxy

Hello everyone,

I have a small home server behind my Fritzbox on which various applications run as Docker images. To reach them from the Internet, I set up Apache subdomains, got a LetsEncrypt Cert for each of them and use the Apache Reverse Proxy function to securely forward requests from the Internet via https. Everything works and has been problem-free for many months.

Now I want to monitor this server with OMD (Check_MK). The installation works locally without any problems, I set up an OMD domain and allow access via the URL
to. Works locally without problems. Now to the reverse proxy for the configuration. Setting up the subdomain, certificate, redirection for http to https - all no rocket science thanks to the Debian packages.

It starts with the configuration of the reverse proxy and I can’t do it. It currently looks like this (only the relevant lines …)

SSL ProxyEngine On
ProxyPassMatch (. *) (\ / Websocket) $ “ws: // 5000 / meinOMD / $ 1 $ 2”
ProxyPass / “
ProxyPassReverse / “

I got myself together from my other configurations …

Now I call the instance from the Internet with https: //omdsubdomian.FQDN and - as I expected - I also get the user / password query for OMD. If I have entered this then I will not be forwarded to the start page but it will appear

https: //omdsubdomain.FQDN/check_mk/logi … t =

Not Found
The requested URL was not found on this server.

At this point I am not able to get any information from the Apache debug log. What can be wrong here?

perhaps take a look here:

Greets Bernd

Sometimes it’s pretty easy …
The solution is to set the proxy directives directly on the IP address of the Docker container

So for example …

Server name checkmk.My-FQDN

ProxyAddHeaders Off
ProxyPreserveHost On

ProxyPassMatch (. *) (\ / Websocket) $ “ws: // <IP-Check_MK-Docker-Container>: 5000 / cmk / check_mk / $ 1”
ProxyPass “/” “http: // <IP-Check_MK-Docker-Container>: 5000 /”
ProxyPassReverse “/” “http: // <IP-Check_MK-Docker-Container>: 5000 /”

… and it works!