One of the most important things to consider when building your own home server is power delivery. Not only is the quality of the power supply inside your server important, since it is what regulates voltages and delivers power to your components, but where it gets its power is also just as important. Here in eastern Kentucky, our power flickers quite often because of a stiff breeze causing a tree to touch a wire, thunderstorms, etc. Those flickers or fluctuations, if allowed to enter our devices, can damage them. In the case of a home server, a sudden outage at the wrong moment can cause data loss or even physical damage to your hardware. For this reason, I highly recommend one of the first items you buy for your home server is an uninterruptible power supply.
An “Uninterruptible Power Supply”, also known as an “UPS”, is basically a battery that goes between your device and the mains power supply. You plug the UPS into the wall, then you plug your devices, such as your server, into the UPS, and it protects them. The battery inside the UPS powers your device, and in turn, is constantly being recharged by your mains power. When the power goes out, there is no change-over time like there would be with a generator where your device would lose power before the generator kicked in. You might hear the click of a relay, and a fan might kick in to cool the battery as it discharges, but your devices won’t lose power. An UPS also regulates and cleans up power before it is delivered to your devices. The power coming in from your mains is often dirty and noisy with regular fluctuations up and down. An UPS cleans it up and offers a much cleaner, more consistent source of power for your device, which in turn can lead to improved system stability in instances where dirty power might cause a system to malfunction.
An UPS, in my opinion, is a must have for anybody who operates a desktop PC, even if it’s not a server. I can’t tell you how many Reddit and forum posts I have seen from people asking for support with a problem they’re having as a direct result of a power flash, surge, brown-out, etc.
Source: https://www.reddit.com/r/pcmasterrace/comments/81e78c/this_is_what_i_get_for_trying_to_game_through_a/
On more than one occasion a friend or family member’s deep freeze has been fried by rapid power flashes, and they didn’t realize it until they went to get something a couple of days later and found their deep freeze half thawed out. A generator is nice because if your power goes out completely, it can continue to power your devices for as long as you can keep fuel in it, but even if you have an automated generator that starts itself, there is that changeover period between the power going out and the generator firing up, which means your computers still get hit with the flashes, brown-outs, surges and other nastiness coming in from your mains power. That is where the UPS comes in, it’s like a surge protector on steroids. Even if you have a generator, the UPS can protect your devices in real time against the events that actually harm them, and keep them running until power is restored. An UPS can even straight up disconnect the incoming power on its own and revert to battery power if the incoming voltages dip too low, spike too high, etc. (no actual outage necessary), again, protecting your device not only from regular outages, but from all the garbage that comes in on the mains.
Link: https://play.google.com/store/apps/details?id=com.nitramite.apcupsdmonitor&hl=en_US
There are a variety of different manufacturers and sizes of UPS devices, suitable for different use cases. Many of the larger ones can even be configured or interacted with using your PC. For smaller appliances, such as if you only want to protect a television from rapid flashes, but not necessarily keep it running for long periods of time, you can get smaller ones that just look like glorified power strips and cost you less than $100, some of them even less than $50.
For larger applications, the sky is the limit really. There are huge units designed to be rack mounted and aimed at enterprise applications that can cost tens of thousands of dollars.
For personal use, I like the units rated for the 1500VA/900watts . They offer a good value, ranging between $100 and $200 depending on the manufacturer, and offer a decent runtime in most scenarios so that if the power goes off for an extended period of time and you’re doing something, you’ve got plenty of time to finish what you’re doing before the batteries die. They generally have more battery powered ports on the back than the smaller units, and at nearly 1000 watts capacity, they can even run a powerful gaming PC at maximum load for quite a while.
You can use an UPS to power anything that doesn’t exceed its capacity, it doesn’t have to be a computer, but when you’re using it on a server/PC, one thing you absolutely should think about is management software. If your UPS has a management port, it should come with a management cable, usually USB to RJ-45, that allows you to connect a PC to the UPS. My UPS units are all APC brand. If you are running Windows there is official software from APC called PowerChute. If you are running Linux there is a free, open source solution called apcupsd. PowerChute on Windows uses a GUI, and apcupsd on Linux uses the terminal. CyberPower appears to have its own management software for both Windows and Linux. I would assume most UPS manufacturers provide some sort of management software. Some useful things you can do with the software include, but are not limited to, the following:
- Monitor the current status of the UPS and issue system notifications
- Configure a “master” port which kills power on other ports on the UPS when the power draw on the master port drops to a certain point, such as killing the power to your monitor when your PC shuts down, and restoring it when you turn your PC back on (This feature might be APC specific, I’m not sure)
- Trigger scripted actions based on the status of the UPS, for example, triggering a graceful shutdown if the UPS battery drains to a certain point and there’s no incoming power.
An UPS is an invaluable piece of equipment because it protects your devices from irregularities in the power that comes from your mains. If you’re going to operate a home server, I highly recommend one, and even if you’re not using one on a PC or server, I would recommend considering one for any piece of electronics that might be harmed in the event of a power surge, brown-out, flash, outage, etc. Exactly which one you use is up to you, but if you’re using one in a conventional home setting and you’re unsure, go for a 1500VA one. Those seem to be the biggest “consumer” grade models that most manufacturers make before you start getting into some serious cash, rack mounted chassis, etc. If you’re going to use one on a home server, be sure to set up management software so that if you’re not around, the PC can automatically hibernate or shut itself down in the event of an unexpected outage.
For some, $150 might seem like a lot of money to pay for something that isn’t strictly necessary for your server to function, but when you’re putting personal files on that server, relying on it for services when you’re outside your home, and spending upwards of $500 per drive for storage, $100-$200 for a good consumer grade UPS is an acceptable insurance policy against the inevitable threat of hardware damage or data loss due to a power outage.
I may do another article specifically about setting up and configuring apcupsd on Linux with an APC brand UPS, but I wanted to take this opportunity to explain what an UPS is and why it’s important.
Gerowen's Corner 