With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
fcNameServerTableLastChange
fc Name Server Table Last Change
1.3.6.1.4.1.9.9.293.1.1.2
The value of sysUpTime at the time of the last update to the fcNameServerTable. This includes creation of an entry, deletion of an entry and modification of an existing entry. If no updates have taken place since the last re-initialization of the local network management subsystem, then this object contains a zero value.
Back to CISCO-NS-MIB MIB page.
IPHost Network monitor allows you to monitor fcNameServerTableLastChange on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco multiplexers right now.