With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
fcmISPortClassFCredit
fcm IS Port Class F Credit
1.3.6.1.2.1.10.56.1.8.1.1
The maximum number of Class F data frames that can be transmitted by the inter-switch port without receipt of ACK or Link_Response frames.
Back to FC-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor fcmISPortClassFCredit on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco optical switches right now.