With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cegBufferRejLowMem
Evolved Packet Core Gateway Buffer Rej Low Memory
1.3.6.1.4.1.9.9.731.1.1.2.9
This object represents the total number of times, buffer allocation is rejected due to, low memory availability in the gateway.
Back to CISCO-EPC-GATEWAY-MIB MIB page.
IPHost Network monitor allows you to monitor cegBufferRejLowMem 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.