03-12-2013 04:03 AM - edited 03-07-2019 12:11 PM
I have a cable from an SFP module in a WS-C3750-48P with 12.2(55)SE1 running to a Gigabit port on a Cisco WLC. After the switch recovers from a power failure, the gigabit autonegotiation fails. The cure is a long drive to unplug and reseat the SFP. Note this happens at too many similar sites for this to be a loose connection. Interface shutdown then 'no shutdown' is not sufficient. The state is 'line protocol is down (not connected)'.
Interface is configured for switchport mode trunk (auto speed, auto duplex). Command 'switchport nonegotiate' makes no difference. Any ideas? Is there a more powerful command than 'shutdown' which might toggle the interface signals? Is there some way of resetting the SFP?
sh int gi 1/0/1 displays 'media type is 10/100/1000BaseTX SFP' and zero packets received.
03-12-2013 04:35 AM
Hello John,
Which is the model of the SFP?
Best regards,
Alex
03-12-2013 04:56 AM
SFP assembly part number : 73-7757-03
SFP Mpdule revision number : A0
03-13-2013 01:48 AM
Hello John,
Please check if the SFP is one of these models:
If you hardcode the speed of the interface does the SFP work properly?
Best regards,
Alex
03-13-2013 05:43 AM
Firmware version 12.2(55)SE1 seems valid for a WS-C3750-48P with GLC-T and min release 12.2(53)SE.
Fixing speed I have tried and makes no difference. While I can encourage others to check their own ios versions, I shall have to live with occasionally reseating the SFP modules.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide