With IPHost Network Monitor you can run simple snmp requests against a IBM device in your network.
ibmfrBRSTrafficClassTotalLastBytesOverflow
ibmfr BRS Traffic Class Total Last Bytes Overflow
1.3.6.1.4.1.2.6.119.4.4.4.1.4.1.33
The total number of bytes for packets that could not be transmitted for this traffic class before the counter was being cleared.
Back to ibm-ibmfrbrs MIB page.
IPHost Network monitor allows you to monitor ibmfrBRSTrafficClassTotalLastBytesOverflow on IBM device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring IBM switches right now.