Last week I blogged about designing a private cloud infrastructure, based on the practices employed by the major cloud service providers.
Today I got a taste of the scale of some of those cloud operations, when Microsoft gave an online presentation on Windows Azure to their International Customer Advisory Board (ICAB) for Server and Cloud (of which I’m a participant).
Remember the shipping contains that I mentioned as units of scale in a modern datacentre? Here are a few stats about Microsoft’s Azure datacentres:
- Each datacentre runs at around 95°F (or 35°C): that’s pretty warm but, even though there is air conditioning installed, it’s rarely used, as the containers are self-cooling (using a water system).
- Containers are stacked in units that are two high and then connected to power, water and networks. (Now that’s some appliance!)
- Each container unit contains around 2500 servers and a whole datacentre has 360,000 servers.
- The containers are normally dark – I described resource decay in my earlier post – that means that it’s rarely necessary to enter the datacentre.
- In fact, the datacentres are so highly automated, that there are just 12 staff: 9 armed security guards and 3 administrators. (I’m guessing that’s working 3 shifts, so only 3 or 4 on duty at any one time.)
- Humans are never alone – systems exist to ensure that people can only enter in pairs, and leave in pairs too.
- So far, Microsoft has spent $2.5bn on its six Azure data centres, with more planned (and that doesn’t include the datacentres for its other operations).