How to run a service on subdomain instead of port on AlmaLinux with Cpanel? - service

Question

I have a version of keycloak running on my AlmaLinux server. This service runs on port 8080. I can access it using <SERVER-IP>:8080. I however, want to access the service using mysubdomain.mymaindomain.com. This way, the user is not confronted with port-numbers, and I suppose using autoSSL is easier (I cannot get it to work on a different port).
I tried multiple things.
The first (I know, very sketchy) was rerouting using htaccess. I made a rewrite condition that looped to localhost:8080. At first glance this worked, but redirects did not work. I suppose this is, since the service thinks it runs on 'localhost:8080' (what it of course does), and thus redirects (on the browser side) to localhost:8080/home for example.
The second thing I tried was adding this code to the virtualhost config file.
I added this using the WHM environment in the server configuration > apache configuration > include editor. There I tried both 'Pre Virtual Host Include' and 'Post Virtual Host Include' (Originating from here).
<VirtualHost *:80>
DocumentRoot "/public_html/keycloak_public"
ServerName mysubdomain.mymaindomain.com
# Other directives here
</VirtualHost>
That did not work, I found out I had to use a proxy. So I appended the following code behind the former part. (Originating from here).
<VirtualHost *:80>
ServerAdmin me#mymaindomain.com
ServerName mysubdomain.mymaindomain.com
ProxyPreserveHost On
# setup the proxy
<Proxy *>
Order allow,deny
Allow from all
</Proxy>
ProxyPass / http://localhost:8080/
ProxyPassReverse / http://localhost:8080/
</VirtualHost>
However, when I go to mysubdomain.mymaindomain.com this still loads the empty directory, instead of the equivalent of :8080.
According to the above mentioned thread, I have to enable proxy somehow, but I did not find a way to do so in Cpanel, so I kind of assumed it was enabled (I'm sorry). Can that be the problem, or should I look somewhere else in order to fix this problem?

Answer 1

The solution turned out to be replacing the * with the server-ip!