Web server behind a web server
I’ve acquired a new server which is to supply services to a certain group. On most cases, I would have used PREROUTE chain in my IPTABLES on my router for prerouting, based on a rule such as this:
iptables -t nat -I PREROUTING -i <external_Interface_name> -p tcp -s <Some_IP_address> –dport 80 -j DNAT –to-destination <New_server_internal_IP>:80
I can do this trick to any other port just as well, however, I already have one web server inside my network, and I cannot know the source IP of my special visitors. Tough luck.
Reverting to more application-based solution, I can use my existing Apache server, which listens on port 80 alread, and gets its requests already, with mod_proxy directive and Name based Virtual Hosts.
Assuming the name of the server should be domain.com, and that the DNS entries are correct, I would add such a directive to my vhosts.conf (or whatever other file containing your Apache2 Virtual Servers configuration):
<VirtualHost *:80>
ServerName domain.com
ErrorLog logs/domain.com-error_log
CustomLog logs/domain.com-access_log common
ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
ProxyPass / http://<Internal_Server_IP_or_Name>/
ProxyPassReverse / http://<Internal_Server_IP_or_Name>/
</VirtualHost>
I’m not absolutely sure about the need for logs, but I was able to see few issues by using them, such as that the internal server was down, etc. I can see that the internal server is being accessed, and that it’s working just fine.
A note – If it’s the first Name Based Virtual Host you’ve added, you will need to “readjust” your entire configuration to a Name Based Virtual Host. Name agnostic and Name based cannot reside on the same IP configuration. It just won’t work.
