With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
mplsInterfaceOutDiscards
mpls Interface Out Discards
1.3.6.1.3.96.1.2.1.7
The number of outbound labeled packets, which were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a labeled packet could be to free up buffer space.
Back to MPLS-LSR-MIB MIB page.
IPHost Network monitor allows you to monitor mplsInterfaceOutDiscards on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco mobile switches right now.