The initial plans that Facebook drew up were to simply replicate its Oregon data center and implement the same in its Forest City, North Carolina facility. But in due course of time the company realized how much their network traffic had changed and that they needed to think of something different for their new facility. Then came the decision to rejig everything. The North Carolina facility has therefore been given completely overhauled networking infrastructure in order to cater to the growth of traffic due to the growth of its internal services. This overhaul was accompanied by a revamp of servers as well. While the data center building is pretty much similar to the one in Oregon, the inside is very different.
Facebook has changed the internal network to include aspects like installing network cards in the servers, switches and routers. There is also a layer 3 network in place. Facebook has also opted for flash storage.
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