Cisco Switch to Cisco Switch using QSFP-40/100-SRBD to 40G-SRBD

[jcp6649]

I am having trouble getting link between Nexus7K and Nexus9504 using 40/100G to 40G BiDi.

Nexus 7k side has module that is 40/100 so it gets the 40/100 BiDi while the Nexus 9504 side has a 40G only module and gets the 40G BiDi. The Cisco compatibility matrix shows the 40/100 BiDi is not supported on the 40G only module just the 40/100 module. I have tried setting speed to 40000 with no luck. It's a direct fiber run(up and over) no structured cabling involved.

This link states it should be able to work: 40/100G QSFP BiDi Transceiver's Backward Compatibility With 40G BiDi - Cisco Blogs

Does anyone have an example of using 40/100 BiDi to 40G BiDi successfully with Cisco modular chassis? 

Thanks in advance.

[Tom Randstrom]

The interop matrix for QSFP-40/100-SRBD transceiver doesn't show the 7K product line as compatible .

The QSFP-40G-SR-BD and QSFP-40/100-SRBD show support on 9K product line. 

[jcp6649]

Thanks for the response, Tom. I was going off of this:

Can you share the link where you see the 7K line being incompatible?

Thanks

[jcp6649]

[jcp6649 · Accepted solution]

We were able to get link by adding "speed 40000" to the 40/100 BiDi side...left the 40G BiDi side to default. FYI. This also worked on the inverse..meaning the 9504 was 40/100 Module and the 7700 was 40 only Module. Same thing.."speed 40000" on 40/100 side but the 9504 also needs "no negotiate auto"...the 7K didn't like "no negotiate auto"

[Tom Randstrom]

Sorry, I must have overlooked the listed N77 family.