How to enable CDP in Cisco UCS Blades
1- Login to Cisco UCS Manager
2- Click on LAN tab

Click on Policies > Network Control Policies >
Add New Policy

Click OK .
Now go to Servers > Server Profiles > Server Profile (your server name ) > vNICs >
Click on the vNIC on which you want to enable CDP .
on the Right pane under the policies

Click on network control policy drop down button
Choose your policy and apply it .
Now on ESXi host Network interfaces you would be able to see the CDP information .