I have Two UCS-FI-6454 Fabric Interconnects that I want to use QSFP-H40G-CU1M DAC cables to connect to a C9500-24Y4C switch and I am having an issue with the links coming up.
On the Cisco compatibility matrix is states "The 40G DAC can only be supported when auto-negotiation is disabled on both ends"
When I plug in the QSAP and do a "show interface hundredGigE 1/0/25 transceiver properties" on the 9500 switch, it shows that it detects the transceiver. But when I do a "show interface hundredGigE 1/0/25" it shows the interface is down and the line is down.
I have went into config terminal and went to the interface and entered "speed negotiate" and the interface will still not come up on the 9500 switch.
I think there is something that needs to be done on the 6454 Fabric Interconnect on the interfaces that the QFSP is plugged in. I have configured the interfaces on the Fabric Interconnect as uplink ports, but I do not how to disable auto-negotiation on them.
I am not even sure if that is the cause of the issue. Does anyone have any suggestions? Is this cable even truly compatible in this situation (switch to fabric interconnect) or should I use a QSFP-H40G-AOC1M that does not requote auto-negotiate to be disabled instead?
