That “Forbidden” page is served up by an Apache webserver.
Only one application at a time can listen on any given socket. The first server that starts will claim the HTTP socket for itself, preventing the other server from accepting any connections. You can run Discourse alongside Apache, but it requires a specific setup:
- Apache needs to run with
mpm_event
,mod_proxy
,mod_proxy_http
and probablymod_proxy_balancer
. - You must modify Discourse’s configuration: disable SSL support and expose
"127.0.0.1:4000:80"
. - Change your Apache config to proxy requests for
forum.gameguides.fr
to Discourse atlocalhost:4000
.
You can find further info and examples here on meta. Some Apache config samples are here and here.