With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
vlanTrunkPortVlansXmitJoined2k
vlan Trunk Port Vlans Xmit Joined2k
1.3.6.1.4.1.9.9.46.1.6.1.1.23
A string of octets containing one bit per VLAN for VLANS with VlanIndex values of 1024 through 2047 in the management domain on this trunk port. The first octet corresponds to VLANs with VlanIndex values of 1024 through 1031; the second octet to VLANs 1032 through 1039; etc. The most significant bit of each octet corresponds to the lowest value VlanIndex in that octet. If the bit corresponding to a VLAN is set to '1', then this VLAN is presently being forwarded on this trunk port, i.e., it is not pruned; if the bit is set to '0', then this VLAN is presently not being forwarded on this trunk port, either because it is pruned or for some other reason.
Back to CISCO-VTP-MIB MIB page.
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