With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
rttMonApplLatestSetError
Round Trip Time Monitor Appl Latest Set Error
1.3.6.1.4.1.9.9.42.1.1.12
An error description for the last error message caused by set. Currently, it includes set error caused due to setting rttMonApplFreeMemLowWaterMark greater than the available free memory on the router or not enough memory left to create new probes.
Back to CISCO-RTTMON-MIB MIB page.
IPHost Network monitor allows you to monitor rttMonApplLatestSetError on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.