How to implement a reverse proxy for one subdomain - reverse-proxy

Question

I have a set of servers behind a firewall. It only supports port forwarding. So far all my subdomains (www., server., beta., cloud.) are all on one server (OS X Server).
I also have a dev. subdomain that is on a separate Freebsd server. form my internal network i can use my DNS to send traffic to the correct server for the dev. subdomain. but when i access from outside i cannot get to the dev server via port 80 as that port is forwarded to the main server.
Rather than using a none standard port I would like to reverse proxy back to the dev server from my main server but it looks like this is for URL's not for subdomains. Is there a way i can route all requests for dev.example.com to the internal development server via my main server.
Thanks..

Answer 1

Yes, that's a standard use case for all common rproxies, and you'll find almost ready to use examples in their respective documentations. With nginx the basic setup will look like this (put this a file in the enabled-sites subdirectory):
server {
# prod marked as default so lost traffic ends up on production
listen 192.168.0.1:80 default;
server_name production.your.domain;
access_log /var/log/nginx/production-access.log;
location / {
proxy_pass http://your.production.server:80;
}
}
server {
listen 192.168.0.1:80;
server_name dev.your.domain;
access_log /var/log/nginx/development-access.log;
location / {
proxy_pass http://your.development.server:80;
}
}
With Pound you could use something like
Service
HeadRequire "Host: .*production.your.domain.*"
BackEnd
Address your.production.server
Port 80
End
End
Service
HeadRequire "Host: .*dev.your.domain.*"
BackEnd
Address your.development.server
Port 80
End
End
# and a safety net for lost traffic
Service
URL "/"
Redirect "http://production.you.domain"
end;
Apache's mod_proxy is also possible, but due to lack of hands on experience with that combo I had to borrow an example from an Atlassian documentation webpage:
# Put this after the other LoadModule directives
LoadModule proxy_module /usr/lib/apache2/modules/mod_proxy.so
LoadModule proxy_http_module /usr/lib/apache2/modules/mod_proxy_http.so
# Put this with your other VirtualHosts, or at the bottom of the file
NameVirtualHost *
<VirtualHost *>
ServerName confluence.example.com
ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
ProxyPass / http://confluence-app-server.internal.example.com:8090/
ProxyPassReverse / http://confluence-app-server.internal.example.com:8090/
<Location />
Order allow,deny
Allow from all
</Location>
</VirtualHost>
<VirtualHost *>
ServerName jira.example.com
ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
ProxyPass / http://jira-app-server.internal.example.com:8080/
ProxyPassReverse / http://jira-app-server.internal.example.com:8080/
<Location />
Order allow,deny
Allow from all
</Location>
</VirtualHost>