To prevent this you alias the 10.1.1.1 address (cluster address as it is called) on the loopback adapter of the www1 and www2 servers and trick them into to thinking that 10.1.1.1 is a valid address ...

In loopback, an application sends a test message to the loopback address on a machine that is not delivered to the network but is instead returned to the sending application. Applications often use ...