This discussions here is not about me but suffice to say I have had plenty of experience with MMO server clusters, infrastructure design and loadtesting to be able to provide some experienced insight on the subject to folks debating the release of LoTR release setup. I will caveat my post here with the tidbit that each MMO engine is a little (if not a lot) different than others and so although this informations pertains to MMO engines I have worked with it is in no way specific or directly relational to LoTR. Take it for what it is or leave it.
MMOs require many many PC boxes to operate a single "server". These clusters of boxes are often called a server farm. In your server farm you can have as few as 3-4 servers right up to 20-30 (or in the case of WoW, 80+) servers. Truely the number is unlimited but for network management purposes going beyond these numbers in a cluster makes for a logistics and backbone nightmare.
Inside your server farm there are usually 3-4 distinct tasks that are divided up aming the servers. Patching, authentication, database and world/zone servers are a pretty standard jobset. The patching servers are usually nothing more than a customized FTP/HTTP server that allow connections from a game client which is then updated as required using checksums to validate the necessary client files on the patch server. The authentication server is pretty much just that. A server that takes the user name and password from game clients and authenticates the account against the entries in the database, verifies the account is active and flags the clients account for access to their player data. Database servers are... well.. database servers.. duh
They are customized to optimize the datastream between the database and the auth/world servers for player data parsing. The world/zone servers are the boxes that handle the actual player data for specific areas of the game world, including load blancing, as needed, for multiple boxes to handle a single area.
Where all this becomes important is when a company underestimates or overestimates their world's population numbers and is unprepared to deal with the fallout for that. As an example, in MMOs the authentication and patcher servers are generally the hardest hit. As MMOs have grown in size, it is not uncommon for a game client to see massive (even over 1 gig) patches at release to make adjustments (that probably should have been done in beta *sigh*) to the game. PErsonally I dont anticipate a "massive" patch for LoTR due to that fact that yes, eventhough they need some tweaks and adjustments, the game is in a very polished state and I don't forsee any sweeping changes. Even IF a game should reuire massive patches for hundreds of thousands of clients simultaneously though the great part is these patch servers dont have any effect on game server performance because they have zero interaction with the databases or the world servers. This means that players ingame arent having their datastream jammed up by 600k people trying to patch 500MB each into their game client.
Authentication servers are the next lot of servers to get hammered. Every single player trying to connect to the game has to bounce through an Auth server in order for the game to verify their username and password and pass back the appropriate player selection info for their account. The great part about auth servers is they run a VERY simple process that is just a checksum of UID/PWD data against the account database and pass back a small stream to the client. Sure the auth servers can back up but when most database servers today can process thousands (if not tens of thousands) of reuests per second it's kind of hard to imagine a company having to deal with more than 50 thousand login attempts per second and causing authentication issues.
World servers and Zone servers are the heart of every MMO. This is also the area that most people are very clueless about the workings of an MMO. World servers generally take up the lions share of the actual server farm. These are the boxes that share the duties of maintaining world object data for their specific area or landblock. The beauty of technology today is that load balancing server power with today's blade platforms means that as a servers load becomes unmanageable the MMO engine can "recruit" more servers dynamically, "on demand" so to speak, within seconds.
Think of a cluster of world servers under "anticipated" traffic. Lets use an example of 10 servers slugging away happily with average load.. In the wings there are another 20 servers, configured and running just idling away with no traffic telling the master server they are there and waiting for instructions. Then it happens!!!! AMG a Gandalf sighting in section 13B!!!! All of the sudden hundreds of players swarm into section 13B to hail the mighty white wizard and the poor server(s) running that section begin to panic. They reach their predetermined "performance" threshhold and send a panic'd scream for help to the shard's master server. After some gentle reassurance to the beseiged world server the master server reaches into the overflow server pool and assigns backup servers A, B and C to alieviate some of the load from sector 13B. Thirty seconds into the great lagfest that was sector 13B the overflow servers step in and all of the sudden the lag becomes more bearable.. all of the sudden the 500 hobbits charging the brandywine bridge trying to head off Gandalf the Gray are actually able to move again and the world is a better place..
Configuring servers the first time is tough. I've been there
Optimizing the servers and software for maximum data throughput and performance levels takes time but once it is done, replication is accomplished in minutes / hours not in days or weeks. Having a server farm of xxx servers, a good network team can configure the appropriate database/world servers in hours. If release is a raging success and they STILL end up swamping their entire overflow pool of servers it's a matter of mere hours to load their software and configure NEW DB and world servers once they are made available from the service provider.