With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cswStackPowerMasterSwitchNum
csw Stack Power Master Switch Num
1.3.6.1.4.1.9.9.500.1.3.1.1.4
This object indicates the switch number of the power stack master. The value of this object would be zero if the power stack master is not part of this data stack.
Back to CISCO-STACKWISE-MIB MIB page.
IPHost Network monitor allows you to monitor cswStackPowerMasterSwitchNum on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.
