The following are the requirements for the Nexus 1000V implementation:
The physical switch should be a Cisco switch.
CDP (Cisco Discovery Protocol) should be enabled on the physical switch and Nexus 1000V.
SNMP should be enabled on Nexus 1000V
The discovery of the ESX host and the Nexus 1000V switch is required, to allow the discovery of the CDP cable connection.Note:
If the ESX host is not discovered, then the CDP cable connection cannot be discovered.
To create connections between a physical switch and an ESX server, Cisco Discovery Protocol (CDP) should be enabled on both the physical switch and the vSwitch (Standard vSwitch, Distributed vSwitch and Nexus 1000 vSwitch) installed on the ESX server. CDP should be running in both Listen and Advertize mode. If CDP is not enabled in both Listen and Advertize mode, then the connections between the physical switch and the ESX server will not be created.
The ESX hostname should have an entry in DNS server mapping to ESX IP address.