Testing for this year's MeKa event showed that my old Cisco
Catalyst WS-C2940-TF8-S switches (shake,
rattle, and roll) are very picky about
the SFP modules they accept. Cisco-branded only, please!
That policy by Cisco from around 2003 caused much hoopla in the industry, and Cisco was effectively forced to accept any MSA-compliant transceivers with with later IOS versions (12.2ish).
These switches are running something around IOS
12.1(22)EA14, though, and they won't accept a service
unsupported-transceiver command. They do accept an
no errdisable detect cause gbic-invalid but it doesn't
help in any way even for Agilent SFPs. (The port is just stuck and
remains so, even when putting in a proper Cisco SFP instead. A cold
restart is necessary.)
So in the aftermath of the meeting, I ebayed two GLC-SX-MM SFPs with them bridges on (19.98 EUR for the pair, incl. shipping). Just to have a few more fibre options in my lab...