debug $port $ip recovery

Hello, we had a power out today. Got home from work and the NAS LED lights on the front were flashing saying 

Boot from USB
Failed!

I tried turning the unit back off then on again. Same thing.

 

So I followed the procedure to book from a USB. This worked.

 

However now I get this message  

DEBUG: $PORT
$IP Recovery

I have absolutely no clue what this means?

 

My files are all backed up luckily however would like to see if my NAS still works.