8ch 8POE NVR running fine with 7 3mp50ir. I was rearranging cables. And unplugged the power cord to NVR and plugged it in to another outlet. NVR would not reboot, all I had was a light blue screen. I gave it 30 minutes to reboot but no good. Took the 6TB hard drive out and NVR rebooted without HDD. Put HDD back in, it did not reboot just like before a light blue screen. Took out HDD hooked it up to desktop computer and reformatted it. Put HDD back in NVR and it booted normal but 15 days of video was gone, no big deal. 

Now if I lose power will my NVR go blue screen of death on me?

Do NVR's need battery backup? Or UPS?

Have you guys run into this before?

This is the second time I have had to reformat a HDD for 8ch 8poe NVR just to get it going again.

Suggestions? Ideas for me if this happens again.

Thanks