We have a bank of five CRS125-24G-1S. We also have a Cisco WS-C3560-24PS switch
One CRS was upgraded to V6.43.7. That unit will not connect to the Cisco. The symptom is that both units (Cisco and Mikrotik) have flashing link lights. The Cisco is logging ethernet up, ethernet down a few seconds apart.
I tried turning off auto-neg and locking the Mikrotik's port to combinations of speed and duplex without any success.
Moving the connection back to a CRS running V6.43.4 resolves the problem.