Google 9 datacenters + www, www2 & www3

Explain Google update & relation to datacenters

[jbgilbert]

There are at least 2 "dance tools" on the web.

you can examine all 9 data centers OR
www, www2 & www3.

I can't tell anymore which ones to look at!

Can somebody FULLY explain the inter-relationships of "the dance" process AND all the data centers AND www, www2 & www3?

[musicman]

jbgilbert,
have you read [webmasterworld.com...]
which explains it a bit further. I've seen a more complete description in a thread recently, but can't find it just now. From what I remember, each of the 9 datacentres will update to the new index over a period of (usually) days, although last time longer. Using www.google.com will take results from any of the 9 centres according to load & how busy they are, so during the update period results may vary according to which datacentre it diverts to.

[Receptional Andy]

Google has over 10,000 linux servers, which are placed in one of 9 data centres (like www-fi). When you search at Google.com, your query is routed (by DNS) to one of the 9 data centres.

During the dance, the new index is transferred from one server to another, with the effect of the data centres updating one by one. Because a search at google.com returns results from one of the data centres and during the dance their can be different data on different servers, it's possible to see the old and new results on Google between searches (this variation = dancing ;))

www2 and www3 are not servers - they are merely domain names set to show results from one or other of the data centres, presumably for testing purposes, and convenience.

Unfortunately there is no fixed pattern or order to when the different datacentres update with the new index, so the best bet is to use a tool to query all of the data centres and see which ones have new backlink counts.

[Brett_Tabke]

Thanks Andy.

And lets just remember that since Dominic [webmasterworld.com], all bets are off.