With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ciscoDlswVirtualSegmentLFSize
cisco Data Link Switching Virtual Segment LF Size
1.3.6.1.4.1.9.10.9.1.1.7
The largest frame size (including DLC header and info field but not any MAC-level or framing octets) this DLSw can forward on any path through itself. This object can represent any box- level frame size forwarding restriction (e.g., from the use of fixed-size buffers). Some DLSw implementations will have no such restriction. This value will affect the LF size of circuits during circuit creation. The LF size of an existing circuit can be found in can be found in the RIF (Routing Information Field).
Back to CISCO-DLSW-MIB MIB page.
IPHost Network monitor allows you to monitor ciscoDlswVirtualSegmentLFSize on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.