With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swMSTPStpAdminState
Switch MSTP Stp Admin State
1.3.6.1.4.1.171.12.15.1.1
This object indicates the spanning tree state of the bridge.
Back to MSTP-MIB MIB page.
IPHost Network monitor allows you to monitor swMSTPStpAdminState 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 access points right now.