With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
vsiSessionEntry
vsi Session Entry
1.3.6.1.4.1.9.9.162.1.2.1
A vsiSessionEntry is a set of objects that together represent the status of each instance of VSI protocol and the slave in an ATM switch to which that instance corresponds. There is one vsiSession for each slave. The number of slaves is discovered via the VSI protocol. Each slave is responsible for a subset of the total number of external interfaces on the ATM switch. Session entries refer back to their respective controllers via vsiSessionControllerIndex, and are in turn referred to by vsiLogicalIfSessionIndex in the VsiLogicalIfEntry. These entries are never deleted.
Back to CISCO-VSIMASTER-MIB MIB page.
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