Duplicate address detection (DAD) is utilized to confirm that an IPv6 address is extraordinary on the LAN before the address is allocated to a physical interface. DAD is empowered in the default IPv6 design and can be reconfigured, debilitated. DAD can be valuable in assisting to troubleshoot erroneous answers to DAD requests. If DAD confirms that a unicast IPv6 address is a copy, the address is not utilized. If the link-local address of the VLAN interface is discovered to be a copy of an address for another device on the interface, the interface stops processing IPv6 traffic.