Inside the data centre - the gap between the image and the reality

Advice Altay Guchveren Nov 30, 2012

When your cloud company offers 'unparalleled service' with a 'distributed architecture' should you be worried?

If we ever got time to read our own publicity, most data centre project managers would be shocked at the contrast between the public image of their company and the view from the patch panel. The 'virtual image' of the company projected by marketing is always several classes of technology ahead of our reality.

The engineer in the cold aisle of the data centre is a bit like a foot soldierin the trenches, while the people upstairs are like the officer class of the service army, well away from the front. The best we might hope for is a one day truce and a game of football with the opposition (aka the clients). Meanwhile, the marketing officers are sending out boastful round-robin Christmas cards, telling everyone what a wonderful year they've been having and what great progress they've made.

The engineer in the cold aisle of the data centre is a bit like a foot soldierin the trenches, while the people upstairs are like the officer class of the service army

You're not likely to even meet the marketing manager unless he or she has had a few too many at the Christmas party. Even then the conversation is always awkward, as we speak different languages. This leads to a disparity between what the company says it can deliver, and the reality.

What they say, and what they do
It's usually only when we’re staffing the stands at trade shows and we actually get round to reading the company’s own sales literature, that we realise the full extent of this disparity.

There’s a skill to interpreting them as they usually have a double meaning. Distributed – as in data, or the workforce – means pervasive, when used by marketing staff.  To the support staff, it means 'all over the place'. As in, what's happened to our secure data strategy? It's all over the place.

Unparalleled is another great word. It could mean you are second to none. But it's more likely to refer to an outfit nobody wants to emulate. As in “I wouldn't want to be you”.

Here's an example: "unparalleled" PUE. Power usage effectiveness (PUE) is one of the criteria on which a cloud service provider might choose a hosting company.

It sounds simple, but it’s not: there’s something not quite right about PUE values. PUE is a calculation based on how many watts of over-head power is used to provide 1W of power to a server. A PUE of 2 is 2W over 1W. Obviously, data centres try to get as close to 1PUE as possible because this obviously makes them appear to be a green and efficiently run DC.

In practice,  unparalleled means there are no back-ups for any critical piece of equipment, such as the power suppliers or the generators. At least, it did in one of the companies I worked for. And that was a Tier 3+ host with a fantastic reputation for building data centres. If the Tier 3+ suppliers are like that, I shudder to think what some of the Tier 1s were like. It's certainly something worth thinking about when it comes to choosing a supplier.

When it comes to PUE the marketing men and the comms workers start from different places and use different metrics. When claiming to have a low PUE the people responsible for publicity might base their estimate on selective criteria for the power they include in their calculation. They may well factor out some of the variables that are inconvenient.

The bottom line is that the PUE can often be misleading. If a company has a low PUE, they could be lying. Ultimately, this means you can't trust anyone's PUE, which is a bit unfair on the honest vendors.

Power failures
A tier 3 data center should provide N+1 redundancy. This is +1 of everything relating to the equipment and network routes. But sometimes the clients have already paid for what they wanted in the DC, but the host sees that everything is going swimmingly without the back up. So they risk not buying the extra units and can keep this hidden till their equipment is fixed, upgraded or baught when the cheque clears. It's a high risk but highly rewarded strategy. As long as you don't get caught.