Hi all, this is my problem.
I have two buildings in a campus that are connected by fibre, probably only a few hundred metres, and all works well. I'm trying to remove some switches and introduce some new ones. The existing ones are 3550s and have SC Gbics in them. The new switches are 3560s and have LC Gbics (GLS-SX-MM). When I connect these to the fibre, 3560 one end, and 3560 at the other, I get no link light, no matter what I try. I have tried different fly leads, of both 50 and 62.5 as I don't know what type of fibre connects these buildings.
From the testing I've done, it would point to an incompatible fibre, or Gbics that aren't up to the job, although I find this doubtful. I have tried these Gbics in test-lab switches, with the fly leads and all is OK. The only way I can introduce the 3560s is to leave the 3550s in place, and that's not what I want to do.
I can see light coming from the GBICs connected to the switch at both ends, but cannot see light at the other end of the campus, either way. This is why I'm suspecting an incompatible Gbic.
Does anyone have any ideas about this?