With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swL3Dhcpv6RelayInfoServerInterfaceName
Switch L3 Dhcpv6 Relay Info Server Interface Name
1.3.6.1.4.1.171.11.70.5.3.3.3.3.1.3
When the swL3Dhcpv6RelayInfoServerAddress is multicast address, this object indicates the name of the interface, which is connected to the DHCPv6 server.
Back to DES3528-SWL3MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor swL3Dhcpv6RelayInfoServerInterfaceName on D-Link device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring D-Link WiFi routers right now.