Power Management – CompTIA Network+ N10-007 – 3.2


Maintaining a power source is obviously important for maintaining uptime and availability. In this video, you’ll learn about UPS devices, generators, and dual-power supplies.

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An important part of maintaining the uptime and availability of your network is providing power to all of your components. In this video, we’ll look at different options for providing power redundancy in your data center and for your devices.

One common power redundancy component is a UPS. This is an uninterruptible power supply. If you lose power, have a brownout or have a power surge, the UPS can help keep everything up and running by providing this battery backup.

There are generally three categories of UPS. One of them is an offline or standby that will only switch over to battery if you lose the main power source. There’s also a line-interactive UPS that can slowly bring the power up from the battery, which is very useful if you happen to have a brownout.

And an on-line or double-conversion UPS is one where you’re always running from the battery. And if you happen to lose power, no switchover is needed. You’ll simply continue to use that battery until the power is restored.

When you’re looking for the right UPS, you may need to look at the different features that are available. For example, you may want to look at an auto shutdown function. If the power goes out, it will still continue to run. But as the battery grows lower and lower, it will send a signal to your computer to automatically shut down so you don’t lose anything in your system. You can also get a UPS with additional battery capacity.

Some UPSs will last much longer because they have much larger batteries. They also have some that have a different number of outlets on the back. And some UPSs will even have interfaces on the back to use for your phone lines to prevent any voltages from coming through the phone line connection.

If you need a long-term power source if the power goes out, then you want to look at a generator. The generator is an engine that will use fuel to create a power source for the components in your building. This may include every electrical outlet in your building. Or there may be certain outlets that are specifically tagged as being associated with the UPS power.

Of course, a generator is usually not running when the power is available to your building. But when power goes out, it takes a little bit of time to get the generator turned on and up to speed. So there is usually a set of batteries that’s able to provide power for the building until the generator is up and running.

On your individual servers, you can also create power redundancy if the server can support redundant power supplies. And this is a good example of servers that have redundant power supplies installed into those systems. This is designed so that each power supply can handle 100% of the power load. If you’re connecting both power supplies and they’re both running at the same time, then they would normally run at 50% of the load.

These power supplies are usually also hot-swappable. You can hit the button on the top, pull out a power supply while the system is running, put in the new power supply, and turn it on without having any impact to the system that it’s running on. In a properly configured dual-power supply, you would not only have the multiple power supplies, but you would be connecting one power source to one power supply and another live power source to the other. That way, if either one of these power supplies fails or someone happens to disconnect one of those power supplies, the other power supply will keep the system up and running.