4D have been operating UK-based colocation data centres since 2007, and in that time we have never had a power failure. This is a result of industry-leading equipment, as well as the expertise and commitment of our engineers.
In the modern business world, connection to your computer services is essential at all times, and downtime caused by a power cut will lead to: lost working hours, frustrated employees, and disgruntled customers. Without proper power redundancies in place your system will lack the resilience you need to stay competitive.
[What should data centres provide? Download our data centre checklist to see]
Our Data Centre’s UPS
There have been local and UK-wide power cuts affecting our data centre, but these never had an impact on the performance of our clients’ servers. This is thanks to our Uninterruptable Power Supplies (UPS).
Our UPSs sit between the mains power and our equipment, protecting the data centre from power surges, as well as power cuts. The basics of a UPS is that it is a very large battery, which takes power from the mains to charge up, and also constantly feeds power through to the data centre.
[To learn more, watch our video Beginner’s Guide to Server Room UPSs]
UPSs are an integral part of our data centres, but it is 4D’s expert planning and maintenance that has made sure they are used to their full effect. We operate with two high-capacity UPSs at both our Gatwick and Surrey data centres. This provides us with 2N redundancy, meaning each of our two UPSs is capable of running the data centre, protecting our customers systems if one of them fails.
N is the required capacity to run a data centre. 2N means we have double that capacity.
We also regularly test our UPSs to their full capacity to ensure they are fully functioning. It would be much too late if we only became aware of a fault during a power outage.
Our Data Centre’s Generators
Each of our data centres is equipped with two generators, each of which is capable of powering their data centre. This is 2N redundancy again, since one generator would be enough to keep the data centre going in the case of a mains power outage, and we also have an additional generator as a spare.
In the case of a power outage, the generators can be started up within the time it takes to deplete the UPSs’ batteries. This means that there is never a moment when the data centre is lacking power, since the UPS activates immediately, and before it runs out of battery power, the generators will begin recharging it.
Additionally, the generators will be able to keep the data centre powered indefinitely, no matter the length of the power outage. Our engineers can refuel and perform maintenance on one generator while the other powers the data centre, guaranteeing our customers are protected from the effects of the power cut.
Once a month at each of our data centres, we test the UPS and generator system to make sure all of the equipment is working as intended. We cut the data centre off from the mains power grid, and allow the UPSs to take over.
We then activate the generators to feed power into the UPSs. We run each generator one at a time so that it is used to full capacity, as this process quite literally blows the cobwebs off of them, and only using the generators at half-capacity would only be testing them halfway.
This allows us to discover any problems, with the safety net of being able to switch back to mains power if the system fails. We can then fix any of these issues, keeping our data centres ready for an actual power cut if one occurs.
Why We’re so Careful
As well as the downtime caused, sudden power loss can damage equipment and corrupt data. This, in turn, leads to more downtime and expensive maintenance, and potentially the complete loss of some systems if the data corruption is irrecoverable.
As a data centre provider, 4D takes rigorous testing and maintenance of our resilience equipment extremely seriously. Our customers have a wide range of vital services and applications running in our data centres, and it is our responsibility to ensure we maximise up time. Power resilience is a large part of this, as well as: cooling, network redundancy, and cyber security. Our customers include banks and the NHS, because we've got a proven track record of providing consistent reliability.