Between two server rooms on an office campus I have three pairs of fiber with an interconnect panel in the middle. Two of the three pairs were connected before I started here and are working. I cannot get a connection over the last pair for the life of me. I've tested all my patch cables and transceivers and I know they're all good, and I've had the fiber tested and it's good, so I have to assume maybe I've got an incompatibility somewhere?
The SFPs I'm using are 10Gbps/850nm multimode. The patch cables are OM1 2.0mm LC/ST. If I run from one switch to the other with an LC/LC or LC/ST - patch panel - LC/ST they get connected fine. Then if I try to run from one server room to the interconnect panel, no dice. I have tested both polarities to confirm that's not the issue. The cable that's running between that server room and interconnect panel is labeled
04/97 - FTB250MN which I believe refers to a 250um fiber diameter. Is that potentially the issue? I don't know but that might be singlemode fiber?