I have a Cat4507R with WS-X4148-RJ 10/100 ethernet module that is connected to an MRV EM316-EFRM/S1 fiber meida converter which then ships it off to a CPE metro ethernet circuit via single mode fiber. When I set the MRV equipment's RJ-45 port facing the 4507R to 100 full and then the 4507R to
100 full, the link goes out. If I hardcode either side to 100 full and then set either side to autonegotiate, I get an autonegotiated 100 half link. I also tried with a Cat 2900 in place of the 4507R and had similar bad luck. Is there any way I narrow down where the issue is or are there some diagnostics I could use to try to point the finger at either piece of equipment?paperboy