Data Centre Tiers Explained



“Today we are likely to be talking in regards to the different data centre tier levels, whatever they cover and if they’re still relevant.

The info centre tier levels had been first started by the Telecoms Industry Association to determine four levels of dependability within data centres, and how well they might survive a fault such as for instance a mains failure or failure that is cooling.

A few years later, the Uptime Institute brought down their form of the tier standards, which covered four amounts of reliability, nonetheless they also offered a certification option, and right now there’s confusion between TIA and Uptime Institute standards.


We are going to focus on the Uptime Institute’s tiering because that is the the one that a lot of people use. The tiers run through someone to four, with one being the redundant that is least and four being the most resilient.

Tier One has little to no redundancy and if the ability goes, the whole site will go out. There’ll be no power that is back-up plus it’s only useful for applications and systems that you are happy to go offline at pretty much any point.

Tier Two, while it may still have a path that is single energy and cooling, there will be back-up generation systems and some degree of redundancy built-in.

Tier three introduces the idea of concurrent maintainability. This means one down for maintenance, while still providing service through to the data floor and the applications that you can lose any one component, or take.

You may possibly have a slightly lower level of redundancy while these components are out but you will have failover and resilience in there. So you’ll typically have a couple of generators, additional air-con units (so you can take a unit off for maintenance), and some additional UPS. Tier Three is the most common standard within the British which rackspace colocation align themselves to.

Tier Four is the top tier within the Uptime Institute’s degrees of tiering and, with that, you’re taking a look at complete resilience through the entire site. So you’ll have two power that is completely separate, two completely separate cooling paths, two completely split community paths and, generally, a lot more than one feed off the mains grid, and this ensures that you’ll lose any component in the information centre and you’ll nevertheless have full resilience out to the data floor. Each of these power paths will have its resilience that is own in you can think of it like having two Tier Three data centres because you will have Tier Three standard on each of those paths.

There are really tier that is few standard data centres, just because the cost of adding in that additional level of resilience generally outweighs the benefits of doing things like good proactive maintenance and good testing of the systems. What you should really do is go and do your own due diligence. Therefore get go to the facility and meet the data centre team that is running it.

Learn what sort of planned maintenance that is preventative do, uncover what testing they’ve put in place, and what type of monitoring they’re doing.

If they’re doing things such as full building tests that are black-out where a mains failure is simulated, that’s great for ensuring the generators are run properly while the UPS’s are working effectively.

Having a well run Tier Three rackspace colocation will give you much generally better uptime than a poorly maintained and poorly run Tier Four data centre. Another thing that is good look at is the general level of resilience and uptime you’ll need in your systems and applications. Just having the body in a Tier Three or Tier Four information centre is not planning to guarantee you a level that is certain of and you should consider splitting your system, or your applications, across multiple Tier Three data centers – that means you are able to handle your failover and your resilience in the applying layer and you’re not so reliant regarding the data centre itself.

Even a Tier that is certified four centre is only certified to 99.99% uptime, which still means you can have up to 29 minutes of unplanned downtime per year. So an application split across two Tier Three rackspace colocation will give a much higher aggregate uptime than having it hosted in a single Tier Four website.

I am hoping that was helpful and offered a bit of background towards the tier standards you have heard about when taking a look at rackspace colocation, because well as providing a little bit of real-world context as to how you should approach them.

You can call us at 4D to learn more about us and arrange an information centre tour.”