Change a QSFP-4x10G connection to 10G FET connections

[David Correa Garcia]

Hello Community,

Possibly this would be a very strange question since I couldn't find any information on how to do this.

I have a connection with a QSFP-4x10G cable that goes from a Cisco N56128P to the uplinks of a Cisco 2248P FEX. The situation is that I need to replace that QSFP cable and use LC-LC fibers with the respective FET SFPs but I need to perform the change online without disruption.

So my question is: Is it possible to perform this?

My idea would be:

1. Configure the new ports on the 5K as members of the current port-channel for the FEX.

2. Disconnect one QSFP fiber from the FEX.

3. Connect one LC-LC fiber to one of the new ports, attach the fiber to the FEX.

4. Repeat the process with the remaining three fibers.

Any ideas are very welcome.

Kind Regards,

[Wes Austin · Accepted solution]

If your links are in a port-channel between the N5K and N2K, you can replace the links one at a time without disruption. Just ensure the links come back online before replacing the next one.

The port-channel configuration appears as a single logical link between N5K and N2K. As long as the entire Po does not go down, there should be no disruption, as other links in the Po will be utilized during the cable change.

If you are concerned or have further questions about this process, I would advise opening a TAC case to review your config and ensure there are no known bugs that would impact this process.

[David Correa Garcia]

Dear @Wes Austin,

Thanks a lot for this!. As you mentioned that is how I migrate from QSFP breakout to normal LC-LC fibers with FET SFP's.

I did the procedure one by one and the Port Channel was always up.

Cheers!