With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
fcmPortLcClass2RxPbsyFrames
fcm Port Lc Class2 Rx Pbsy Frames
1.3.6.1.2.1.10.56.1.5.1.9
The number of times that P_BSY was returned to this port as a result of a Class 2 frame that could not be delivered to the other end of the link. This can occur when the destination port is temporarily busy.
Back to FC-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor fcmPortLcClass2RxPbsyFrames on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco routers right now.