A real show stopper when doing a HyperFlex Edge/No-FI install is the 25G connection between the UCS HyperFlex hosts and the upstream switch, like a Nexus 9K. Here’s how to make it go smoothly.
When connecting Cisco UCS HyperFlex servers with a VIC 1467 interface card to a Nexus 9k, you need to take care that the FEC mode is correct. So after completing the cabling and before you even try to begin your install, check the CIMC via the CIMC UI and look at the External Ethernet Interfaces. If all interfaces are in a Link down state, as shown below, toggle the FEC mode to CF74 on the connected interfaces.