Mysterious reboots - could UPS battery backup solve it?


I'm going forward. The only thing that's weird is that the media server doesn't have these issues, but it has a laptop-style power adaptor, which probably weighs more than the box itself (Intel NUC ~2014).

I'm in agreement with many of the other comments here that a UPS is a good idea in general. These devices protect your equipment from small surges, brown-outs, and also full blown blackouts, giving you time to ride it out or gracefully shut down the equipment. And since essentially all UPS units have some means of monitoring, you can typically get the status in your logs so you'll have some more data about your power conditions.

If it turns out that it doesn't help, I'd then look into the power supply for your actual device -- if it is always possible that the supply is inadequate (underspec or failing), and that could cause brown-out conditions on your device itself. Or it could be a thermal issue. You can always force this situation by stress-testing it (for example, running multiple concurrent speedtests and other high demand operations will increase the power consumption and thermal loading.

And failing those, maybe there is some random bug or conflict... hopefully your logs would reveal that, in time.

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The power-draw of the device itself and the capacity of and in how good condition any capacitors are in the power-supplies all matter. It's a combination of multiple things and your server probably just simply teeters close enough to the brink that it can't cope with transient voltage-drops on the line.

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Thanks again. This makes great sense.

I just sent a note to Pascal at PC-Engines to order another adaptor in case the original was messed up, and I'll order a UPS unit tomorrow morning.

Thanks again. I'll order the UPS tomorrow morning. I'm fully convinced.

Aircon starting up can dim the lights

I had an odd situation that plagued me for years...

tl;dr - I had to replace all surge protectors for all electronics (some protectors which were 30+ years old).

Over 7 years ago, I realized where I lived did not have "clean power"...mainly because the power flashed all the time (quick brown or even black outs). At one point in time, I replaced a motherboard twice in an x86_64 PC. With this machine on it's third motherboard, I bought a new surge protector (about $20 USD with a $15-20k warranty on equipment connected). I never lost another motherboard (I also bought a motherboard model with built-in surge protection)

In other scenarios, I had an issue where a Ethernet switch would randomly loose power...playing with the wall wart would get it running at times...another device...whenever I touched the power supply, power flash, etc., a Meraki MX60 would reboot...loosing all it's settings and sometimes, wiping its flash and booting into the recovery image. In the Meraki's case, the power supply was bad, and running about 4-5 Volts too "hot".

Both were resolved by replacing the power supplies (wall warts). So I would definitely start by checking checking surge protectors and power supplies.


I now have a combination of UPS and solar/battery backups for networking equipment and sensitive electronics, etc. that I want running 24/7/365, for others, I use good surge protectors if I can function with those devices down during a power outage.

:bulb: You could also make an UPS yourself with: a powerful enough wall wart (13-14 V), solar charge controller, and a 12 V battery - given your device it 12 V, that is.


Oh, we're telling stories here now? Well, I may as well chime in, then!

My husband and I bought our house a couple of years ago and we noticed soon after that every now and then, randomly, the circuit breaker supplying power upstairs would trip. We also get brownouts here and there. Turns out that the previous owners have absolutely fscked up the wiring here and we'd basically have to redo the entire building to fix it all up.

Can't afford such a big task for years to come, so for now we've got all of our important stuff behind line-interactive UPSes. I've slowly been accumulating parts and equipment for a small solar-setup, but it's taking forever due to me having basically zero budget.


I had a IP telephone/Internet gateway a while back that suddenly stoped doing anything but everything seemed to work. A power recycle always fixed the problem for a while but in the end I tried a new power adapter and after that it worked until it was scrapped.

But does the power adapter makes any sound what so ever I would say it has done its lifetime.

I doubt voltage suppressors get fried by low voltage. It is probably more likely the suppressor got fried first without anyone noticing and at the same time or after that the power adaptors started failing.

A faulty ground wire in the house can also make voltage peaks that fries electrical things.

The biggest problem with internet equipment and TV is if the internet comes through telephone line or coax cable. Then the modem gets squeezed in between two different ground potentials and the TV or some of the internet equipment will get fried at first lightning storm.


You bring up a good point...

I had to also make sure all coax, AC ground, radio, negative of the solar batter array, etc. was bonded to to the same ground system!


At one point, I realized the cable (MOCA), and then the phone company (FiOS/MOCA) never grounded the coax blocks to the house grounding system (in my area, is required by Electrical Code)!

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No, that's way too simplistic.

Inductors are prone to making noise, that's simply due to the way they work. Many manufacturers do apply some sort of conformal coatings, hot snot, silicone glue and whatnot to try and reduce that, but over time it is entirely possible that any such coatings or glues may simply come loose enough that the inductor's ringing will become audible. That does, however, not imply in any way or form that the inductor is bad or even worn out. Not even a little bit.


I have simply have no working primary switched power adapters that makes a noise under load. They can however sound a little without load but never under normal load.

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I have plenty of both. I have also plenty of ones that didn't use to make a sound, but the glue has come loose and the power-supplies do make quiet, but audible sound now. I have yet to repair a single device where the inductor was the cause of issues, but e.g. one of my UPSes kept tripping the relay almost every 10 minutes and I fixed that UPS by....replacing a couple of the big input-caps.

Capacitors are definitely the #1 culprit I would look at, if there are any issues with stability.


I would like to add that I don't mean to be rude or dismissive. I have Asperger's and I can come off as a little aggressive. I do agree with your statement to the extent that a PSU that suddenly starts to make noise might warrant inspecting it. I just wouldn't take it as a definite sign that it's bad or going bad.

I hope I did not offend.


Oooh. I love the solar idea. I mostly have southeastern exposure, so I can charge for most of the morning.

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The info about inductor construction and sound damping is useful. I can't speak for @flygarn12, but from my point of view you're among friends.

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I have a lot of network/internet things powered by 12 volts.

Everything is plugged into a small car battery which is charged from the mains.

There are never cuts !!!


I own an apu3d4 having a wifi module, LTE LM940 module and a SSD installed. Once in a while my LTE connections stalls. Sometimes the adapter reseats itself, sometimes a manual resetting of the adapter works but most of the time a reset of the whole device is required.

In the Kernel-Log it can be seen that the USB of the LTE modem is lost and then it tries to reconnect. So something between the driver and the modem screws up. I tried a higher rated power brick which did not resolve the issue.

Not sure if there could be a common source of the problem. Haven't analysed the whole power supply but somehow still have the feeling that there might be a bottleneck. Sometimes it runs for weeks without interruption and then just for a few hours.

What you described doesn't sound like a power-related issue.


FWIW I'm pretty confident that the power supply was the issue for me. I got a CyberPower VP1000ELCD, and ever since the router stays up and running until I reboot it for something, with two-month uptime so far.