Let us say I curently have an internet forum running on one HTTP web server and delay pills work acceptable for more often than not. Now as customers grow tremendously I've no choice but to create the forum a distributed web service spanning over many hosts.

To attain things i referred to, what tools/programs/frameworks will i need?

And if I've several hosts running exactly the same service, how do you make sure the consistency of information (within this example, it might be forum structure, user posts etc) around the hosts? Do they should be shown or something like that?