I have had four routerboards die on me in less then 7 days. They are on my roof powered by a POE 48V units.
The first unit was the older rb230, then an rb500,and now a second rb112. After the Third one died I switched out everything the rb, the ethernet run, the powersupply. The only thing in common was that I'm using .23 of the code.
You can power the units up via poe but thers no more ethernet connetivity. If you to to /system/reset and clear all settings the units reboot and just continue to reboot anytime you try to enter the submenu /ip.
Is there anyone out there with a simular issue?