answer:It depends on how much traffic you have and how data-intensive it is. Also, read-only requests are a lot lighter on resources than read-write. At the extremes, say you are running eBay or Amazon.com – that requires separate servers. And if you get a few thousand hits a day, it probably works just as well either way. Obviously the distance between those extremes is immense, and you have to figure out where your application is. If your site is smaller, you could combine them and you would know pretty soon if you needed a second server. If you make the web application modular, changing the data source later is pretty easy.