So how many data centers, server rooms, and data closets do you think there are in the United States? You guess maybe 20,000? Maybe 100,000? Try 2.94 million, at least according to the box-counters at IDC. This is a much larger number than you might expect, and considering there are tens of millions of small businesses in the US …
Is there a precise definition of a data centre?
I assumed that a data centre was quite a big setup, not to be confused with a mere server room, but it sounds like standards might be slipping.
Quite. If your definition of 'data center' includes a cupboard with a router in it, I wouldn't be surprised to learn that Walmart has more than 20,000 of those.
A bit bigger
Walmart is a step above a cupboard with a router. IIRC their standard store setup is about 3 racks of equipment in a back room. Cisco managed switches, plus a bunch of servers to manage the inventory. Been about 10 years since I saw their setup, though.
Eerie part of Walmart, if you need to call the Home Office for approval to plug in an Ethernet connection and get put on hold, you'll notice that the hold music is the same as the overhead music in the store. Not the same selection, it's piped in.