2960C 8-port gbic no workie

[johnkholmes]

We bought the 2960C 8-port as shown here:

We bought the GBIC as recommended by Cisco, plugged it in, noticed it didn't go orange in the web interface, but it doesn't appear to be getting connectivity to the switch immediately above it in the rack.  We can plug a standard copper CAT-6 into the bottom plug (either works).  Is there something special we need to configure for the GBIC to work?  I've dealt with Cisco switches and routers in the past and it was as simple as plugging in the GBIC, turning on the switch, then pinging beyond it.  Please let me know if you need an sh run or something.

[Leo Laohoo]

What is the model of the SFP?  What is the model of the SFP at the other end?

[johnkholmes]

The SFP on the 2960 is a Long Line 21cfrj class 1

Model No: glc-lh-sm-ddm

1310no 20km 1.25g sfp

On the other side, the fiber goes to Cisco Nexus 2148t fabric extender

GBIC model is a Cisco sfp-10g-lr 10-2457-02 ln#50

[Leo Laohoo · Accepted solution]

This explains it.  One side is 1 Gbps SFP but the other side is 10 Gbps SFP+.  This will definitely won't work. 

Both sides must use 1 Gbps SFP because the 2960C won't support SFP+.

[johnkholmes]

Thanks for your help!  Would you happen to have a recommendation for GBIC on the Nexus?

[Leo Laohoo]

Depends on which Nexus the link is being terminated to.  I believe Nexus 2K supports 1 Gbps SFP.  Don't get the "FET" one.