Power Resiliency – CompTIA Security+ SY0-701 – 3.4

Our computing systems rely on a stable power source. In this video, you’ll learn how UPS technologies and generators can be used to maintain power.


The one resource that connects all of our technologies together and is the foundation of everything we do is the power provided to our systems. We spend a great deal of time engineering our data centers to be able to support the power needs for all of our computing systems. And we also have to consider what’s going to happen to this power if we happen to have an outage. Of course, most data centers don’t make their own power. We have power provided to us by a local provider. And we can’t control how available that power happens to be.

If there’s an outage to the power grid, then obviously we’ll have an outage in our data center. For that reason, we design and develop systems for our data centers and other locations so that we always have some level of access to electricity. This might be an outage that occurs for minutes or hours, or it might be related to a natural disaster, and you may be without power for a number of days.

If you’re without power for a number of hours, you may be able to get through that outage with a UPS. A UPS is an Uninterruptible Power Supply, and it commonly has batteries or some other power source inside of it that allows us to keep up and running even when the main power is no longer operational. The UPS can get us through times when there are complete blackouts, where there’s no power. Maybe there’s a drop in voltage– we refer to that as a brownout– or an excessive amount of voltage. We refer to those as surges.

There are different types of UPSes that you might use depending on your requirements and your budget. Lower-end UPSes tend to be offline or standby UPSes. This is a UPS that is constantly running on main power. But when that main power fails, there’s an internal switch that moves from main power to battery backup. A line-interactive UPS is one that can slowly increase the amount of voltage if you happen to see a drop on your main power line. This can be especially helpful if you live in an area where there tend to be a large number of brownouts.

And if you’d always like to run from battery backup and not have to worry about switching back and forth between main power and battery power, you might want to use an online UPS. You might also hear this referred to as a double-conversion UPS. The batteries inside of a UPS have a limited capacity. So you want to be sure that you get a UPS that is large enough to maintain the system for the amount of time that you’d like to cover during this power outage.

There’s also a number of different features that you can get with the UPS. For example, you can choose how much battery capacity might be in a particular UPS version. And if that battery tends to get lower and lower, you can have the UPS send signals to your systems to automatically shut them down gracefully before the battery power is completely depleted.

You also have choices over the number of outlets that might be available in the back of the UPS. And some UPSes include additional suppression features to plug in an ethernet or telephone cable. If you need more than temporary power, then you might want to look into a generator. A generator provides long-term power backup. And as long as you have fuel, the generator will continue to provide you with power.

Some generators are large enough to power an entire building or a section of outlets inside of the building. If this generator provides partial power, then you’ll probably find outlets inside the building that are marked as generator power.

Most organizations will take advantage of both types of power backups, both the UPS and the generator. This is because the power outage tends to cause the generator to turn on. But there’s a ramp-up process while the generator is starting up. And during that time frame, you may be without power for about a minute. So you can use your UPS to cover that time frame when the generator is not running. And then, once the generator provides power to the building, everything can move over to generator power.