F*EX use case: reverse proxy

You can prosecute F*EX behind a reverse proxy, but then you are limited to the capabilities of this proxy.
For example, if you use apache, then you have a 2 GB upload limitation and a throughput penality.

Example for apache 2.4 reverse proxy

If you want to contact the F*EX server via alias URL https://fex.tandem-fahren.de/ then you have to put in apache's httpd.conf :
  <VirtualHost fex.tandem-fahren.de:80>
        ServerAdmin webmaster@tandem-fahren.de
        ServerName fex.tandem-fahren.de
        ProxyRequests Off
        ProxyPass        / http://tandem-fahren.de:488/
        ProxyPassReverse / http://tandem-fahren.de:488/

and in apache's proxy.conf :

  <Proxy *>
    AddDefaultCharset off
    Order deny,allow
    Allow from all

And write to /home/fex/lib/fex.ph :

  $hostname = 'fex.tandem-fahren.de';
  $reverse_proxy_ip = '';
  @durl = qw(http://tandem-fahren.de:488/fop https://fex.tandem-fahren.de/fop);
See also: http://8d.no/fexproxy.html