Google Data Centers
I bet you thought that when you went to www.google.com you were going to a single place that held billions of web pages. The reality is, when you place a search at www.google.com the results are actually coming from one of these data centers:
www2.google.com
www3.google.com
www-dc.google.com
www-ex.google.com
www-zu.google.com
www-ab.google.com
www-sj.google.com
www-va.google.com
www-in.google.com
www-fi.google.com
These are the locations of the data centers that I was able to track down:
sj is in San Jose
dc is in Washington, DC
zu is in Zurich Switzerland
ex is in Santa Clara
va is in Herndon, Virginia
When Google makes an update, one data center changes and slowly populates the new data to other centers until they finally are all updated with the same data.
This is the "Google Dance."
This is especially interesting right now because there has been a May update (called ‘Dominic’ at WebMasterWorld) that has been in flux an especially long time.
The sj data center has been creating a lot of turmoil for those who keep a close eye on all of this.
Here is an interesting site that talks a bit more about these updates: http://dance.efactory.de/