Setting proxy redirection from other server

Staszek

Not sure where to put it, so off-topic for now.
I have domain, that points to one server (I cannot change that) let's call it myproperurl.pl/flarum, but I want to have Flarum on the other one, let's call it urlofsecondserver.pl, using that domain Both servers are apache. How can I do that, using .htaccess on both servers? Right now, I was able to set up proxy on first server using this rules:

RewriteRule ^[\/]{0,1}flarum$ /flarum/ [R,L]
RewriteCond %{REQUEST_URI} ^[\/]{0,1}flarum(\/.*)
RewriteRule ^(.*) http://urlofsecondserver.pl%1 [P]

The problem is that when I install Flarum (I launch config installer using first server URL), in config I have URL of second server. So when I load FLarum after install, FontAwesome does not work (CORS) and all URLs are set to second server (only URL in browser is ok). But when I change URL in config.php, then everything stops working for some reason - I get nothing in response, both using first URL, and second.

Can anybody help?

Pollux

In general: A) Have Flarum running properly before handling the rewrites. B) Start the rewrite process with simple tasks. I therefore have two questions to begin with:

Is http://urlofsecondserver.pl/flarum/ working properly once it is set in its config.php?
Is e.g. http://myproperurl.pl/test.txt showing the result of http://urlofsecondserver.pl/test.txt (give both test.txt files different content to prove it)?

Staszek

Thanks for your answer.
Before I installed Flarum, I did simple tests, to confirm, that redirection works as expected. I put setting index.php with phpinfo() to second server, and I was able to reach it. Then I installed Flarum. It works ok, when url in config.php is set to http://urlofsecondserver.pl (it is not in flarum subfolder there), but problem is when I change url in config.php to http://myproperurl.pl/flarum (in root there is my webside, which is in yet another second url, and I want Flarum to appear onmyproperurl.pl/flarum).