Test Fiber SFP

[mikegrous]

Is there a way to test whether an SFP in say a 3750 is working correctly?

[davy.timmermans]

if you insert the SFP module you'll see a message on the console that the module has been inserted.

If you have 2SFP's, you can insert them and connect them with a LC-LC cable. If you see amber lights on these ports you can say it's working.

If you've only 1 SFP you can test it if you've a looped cable

[mikegrous]

I know how to physically test it. I am just curious if there are any commands that test it.

[bretjaquish]

The 3750 has online diagnostic tools:

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_25_see/configuration/guide/swgold.html#wp1041595

Besides those commands, you could turn on UDLD to verify the optics are okay.