With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cIsnsNumDd
Cisco iSNS Num Dd
1.3.6.1.4.1.9.10.116.1.1.2.1.2
The current total number of Discovery Domains in this iSNS instance. This is the number of rows in the cIsnsSrvrDdTable.
Back to CISCO-IETF-ISNS-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor cIsnsNumDd on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco routers right now.