Thanks for those tips, I will try using the mount options when I do my tests (forcibly drag out power and up again) to make sure my system can survive power cuts properly. I did re-install armbian just now right before writing this reply and to my surprise everything works perfectly again. The UPS is something I will look into in case I do need it. I don't have that many power cuts, and there is this issue where my internet would take much longer time to come back up then the electricity.
I did attempt to fix it. The logs were of no use, as they ended the time my board got its power cut. As I said I tried restarting sshd manually, but it wouldn't even start, the task was just queued before the kernel crashed. After I pushed my seemingly not so big changes, the box wouldn't even give me a HDMI output, so I just considered the errors to be off bounds for my knowledge and proceeded to reinstall.
Having access to console is indeed good, I have a COM cable where I can probably access the serial console if necessary, but since I put my device inside a case for easy moving it's not that easy to attach the pins, but if it was truly necessary I guess I could plug it in and have the USB end on some other safe device like my router which boots using RAM.
As for the sdcard, I just ran fsck and said there were no errors, more I can't tell if it was corrupted, but I'd assume it was in some way due to the problems I'm having (and it potentially ran fsck itself as per defined in fstab? However, there's nothing in the logs about it. Since I had no logs at all could be it wasn't saved for some reason, and it repaired it before so I couldn't see any fs errors. But I believe the media has to be unmounted for it to be possible unless it does post-booting using tmpfs, excuse my lack in GNU/Linux knowledge it's a hobby after all). It could have been a smart move to get a x64/x86, but I am still sure a small device like this should be able to handle what I need without having to go for something bigger. There is also the fact that Intel is no longer planning to release new Atom-series CPUs which would make me have to go for a bigger CPU in the future.
This sounds very interesting, I didn't think of that. But wouldn't you potentially be charging the battery cells inside to death if it continously draws power and charges it back up again? As you said it only has circuitry for charging/discharging, so as per my understanding it would not be able to directly passthrough the current- But it might be too little to make a difference. I did some tests and I believe some lithium cells on heavy use ended up degrading to 75% of it's original capacity during a period of one and a half year, so if the device does not draw that much energy it should be able to last for a while although it will get less and less hours after some time?
