Has anybody heard of sites being set up in this manner? See Title. Does it provide any advanced security?
It can provide some kind of security if the db server can be accessed only from local area network and not from internet.
This is mostly done to enahnce the performance because webservers are tuned in different ways and database servers in different for optimal performance.
Everything depends on the server configuration but since db serer it can be remotely accessed by a site I dont know ...
It may help for site security but you will surely get better site performance if you run web server and database server separately. Kailash