Prerequisites for a DAD Check

To successfully test an IP interface, at least one port in the host VLAN (Virtual LAN) must be in the Up state. If all ports in the host VLAN are Down, the DAD check does not run.

The DAD check does not run on loopback VLANs; an IP address for a loopback VLAN is marked valid and the address is identified in the show ip dad command display with the L flag.