[c-nsp] 3750-E + CVR-X2-SFP10G + SFP-10G-SR = disappearing media

[Matthew White (MAWHI)]

Greetings,

I have an open TAC case about this but I figured I'd ask here as well.

I recently installed 10 3750-Es in 5 2-member stacks. Each stack has 2 uplinks to a 6509-VSS. I'm using X2 to SFP+ converters and 10G SFP+ modules on both ends of the links between the stacks and the VSS. In each stack I'm using interface Ten1/0/1 and Ten2/0/1. There is currently no "real" traffic on any of the links. The plan is to do a forklift upgrade of our existing production network and I've set the 3750/VSS up in a test environment. With the exception of two hosts talking iperf to each other, the network is quiet.

The problem I'm seeing is this: after about 6 to 8 hours a 10G interface on the 3750 side will go down. Saying 'show int Ten2/0/1' will show the media type as "Not Present":

Full-duplex, 10Gb/s, link type is auto, media type is Not Present

as opposed to:

Full-duplex, 10Gb/s, link type is auto, media type is SFP-10GBase-SR

I am seeing this behavior on three individual switches and in each case it is ten2/0/1 that fails. I've replaced the X2 converter, the SFP+ module and moved the converter to Ten2/0/2 but the symptoms persist. I RMA'd one of the switches and just installed the replacement, hopefully this will solve the problem.

I also checked software compatibilty and the switches are running (C3750E-UNIVERSALK9-M), Version 12.2(53)SE2

Has anyone seen this before?

-mtw