I'd like to configure a reverse http proxy to serve traffic from numerous internal webservers while exposing a single external ip.
I plan to have an externally published wildcard dns for *.domain.com, and then a set of internal records for foo.domain.com, boo.domain.com, etc which could be frequently added/removed to dns.
Thus a user would do a look up for any of *.domain.com and get the same ip, which directs to the reverse proxy. The reverse proxy is configured to use the internal dns to resolve, and the traffic is proxied to the particular internal node.
The requirement that has tripped me up is the ability to add/remove internal dns entries without having to touch the proxy configuration. I've experimented with squid and apache/mod_proxy but could not find a way to do this without specifying each host in the config, which becomes arduous / difficult to maintain.
I imagine this is a problem that has been solved before, though I'm not finding a lot on google. Any suggestions on what proxy tool I should use and any configuration tricks?