I had a rb112 that i didn't use in a while working on routeros 2.9.51
The problem i encountered is that the ether port works randomly
After plugging the Ethernet cable, when i plug the power jack sometimes it works properly and some other times only the green light on the ether port is on and the ether port doesn't work
So i have to make random number of reboots until it works
Same problem happens if i unplug the ether cable and i replug it
When the ether port boots correctly the routerboard works just fine