I just tried to establish a fiber connection between a c4503 and a c2960x using glc-lh-sm modules on both sides, but with no success.
Link comes up on the c2960x but not on the c4503.
I tried "speed nonegotiate" on both sides: link comes up on both sides, but no data received on both sides.
A connection between a c2960-24LC-S and the c2960X-24PD-L works fine, as does a connection between the c2960-24LC-S and the c4503.
All on the same ports and modules and also different ports an modules per switch.
Any suggestions on why a connection between the c4503 and the c2960X doesn't work?
