With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swMldSnoopingCtrlTable
Switch Mld Snooping Control Table
1.3.6.1.4.1.171.12.34.3.2
The table controls the Vlan's MLD function. Its scale depends on current VLAN state (swL2VlanInfoStatus). If VLAN is disabled mode, there is only one entry in the table, with index 1. If VLAN is in Port-Base or 802.1q mode, the number of entries can be up to 12, with index range from 1 to 12.
Back to MLD-SNOOPING-MIB MIB page.
IPHost Network monitor allows you to monitor swMldSnoopingCtrlTable 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 switches right now.