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Comment by lokimedes | Hacker News Reader

A thing that is needed when combining RPi with Unbound, is a way to resynchronize the system time after power cuts. The standard NTP setup is driven by DNS hosts, and Unbound, at least with DNSSEC validation is time sensitive. The ballet of NORESOLVE is a nightmare. This happens easily due to the lack of a realtime clock on the Pi. A local GPS with PPS, a dirty ip-based set of NTP hosts or a shell script can solve it, but this should be part of an extensive guide, in my pained opinion :)

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The easiest solution for 90% of unexpected rPi power-down cases is a small uninterruptible power supply.

Another option is to try to find an old and super cheap laptop and use that instead. Maybe find one with a broken screen or busted keyboard or something that you won't care about.

Laptops basically have a UPS built-in.

Better still, do both. Power your Pi off of your laptop server to get the benefits of its built-in battery acting as a UPS for both devices.

If your laptop's USB ports will provide enough amps, that could work.

Doesn't the Pi 3 expect up to 2.5 amps? I imagine some of that is for powering USB ports, so you could probably get away with 1.5 amps if you're not using them, but even that's a lot for laptop USB. I'd be surprised if any offered more than 1 amp.

This is essentially what my MBP with butterfly keyboard has been relegated to in life. The keyboard is unusable, it's too expensive to repair, but it's not a shitty enough computer to just throw away, and there's practically no trade-in value either. So, there it sits in a closet, on a top shelf, just acting as a remote device doing random things as I assign it tasks.

However, cheap is not how I would have described it ;-)

Are there any you could recommend? Most that I have looked at cost about the same or more as a Pi in the first place and don't even come with batteries.

If you power your Pi via USB just use a phone USB bank that works via passthrough. (I don't actually have one to recommend but just one that can charge and discharge at the same time).

> one that can charge and discharge at the same time

I did some research into this as well and I'd gladly consider this as an option but most power banks can't do this. And the ones that do don't tend to advertise it. Every time someone says they found one that can do this, in some forum or whatever, they are no longer available to buy.

I use a big one (think CyberPower and APC) for a small collection of devices including some network hardware. Smaller ones from those brands or AmazonBasics cost around 50 bucks, battery included. I tried a UPS hat, which would have been the most clean-cut solution, but it failed and the battery bloated.

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