I am doing some physical changes to a dev network. The physical hardware is a Cisco ASR9006 to a traffic generator with duplex MM fiber. I am changing from a 10G traffic generator to a 1G. I am stumped and have not been able to get it to work (down/down from "show int tengig <ports>", rx error on the traffic generator).

What I have done in chronological order:

- Changed the C9k SFP from 10G to 1G. The 1G SFPs are NOT Cisco branded.
- Changed the bandwidth in the running config from 10G to 1G. Committed the changes.
- Verified 1G SFPs are in the traffic generator
- Did a loopback test on the used interfaces of the traffic generator. It worked fine.
- Lunch
- Go back to 10G SFPs on the C9k and put a pair in the traffic generator. Left the speed at 1G in the C9k running config. No dice.
- Went back to the original 10G setup. Worked just fine.


I am lost. Is there anything that I missed here?

**EDIT:**

Additional information.

Avago 850nm SFP (C9k and traffic generator)
Multimode fiber (OM3 50/125), 50micron