These Cisco convertors are pretty handy I must say. It's an X2 Convertor module that is able to take 2 SFP modules; Allowing you to convert an X2 slot to twin SFP slots. Anyway, when you insert a TwinGig to a switch without first doing the pre-configuration, you're most likely to get an error like this:
%C4K_GLMMAN-3-X2PLUGGABLESEEPROMREADFAILED: Failed to read seeprom on port Te2/8. Reinsert X2 module or configure GigabitEthernet port group if TwinGigConverter is installed.It's because the X2 slot you used is configured as a TenGig slot. It should be set to Gigabit for the TwinGig to be detected. The way it's done on an 4900M is:
hw-module module 2 port-group 4 select gigabitethernet The catch is that the 8 port TenGig module used on the 4900M is over-subscribed and you will have to set a "port-group" which represents 2 ports, as "gigabit" to get the TwinGig to work.
After setting our port-group, the log will show the TwinGig is detected:
Nov 23 10:32:06.501: Port Te2/8: TwinGig Converter inserted: vendor: CISCO SYSTEMS, p/n: 800-27645-02, s/n: FDO14290SE5Here are some references for more info:
Installation Notes for the Cisco TwinGig and OneX Converter ModulesSelecting X2/TwinGig Convertor Mode SFP Interfaces of X2/Twin Gigabit Converter Do Not Come Up
