With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
vrNsPacketsFailed
Virtual Router Ns Packets Failed
This attribute counts the total number of packets processed through NetSentry which ended with a fail disposition. This counter will wrap around to zero when it exceeds its maximum value, 4294967295.
Back to Nortel-Magellan-Passport-NetSentryMIB MIB page.
IPHost Network monitor allows you to monitor vrNsPacketsFailed on Allied Telesis device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Nortel switches right now.