Cisco VLAN sensor

The Cisco VLAN sensor uses the Cisco VLAN Membership MIB to discover VLAN contents.

The SnmpMib2Sensor invokes CiscoVlanSensor when VLANs are configured for Cisco devices. The CiscoVlanSensor then invokes BridgeSnmpSensor2 for each VLAN using the ethernet protocol. The sensor discovers the VLAN membership table, creates L2Interfaces, and attaches them to the VLAN bridge.

Note: Default VLANs, token ring, etc, will not spawn a BridgeSnmpSensor2.

Sensor name that is used in the GUI and logs


Object identifiers (OIDs) that are used

The sensor follows the standards documented in RFC 1286 to get the VLAN interface. The high level OIDs queried are:

  • OID . to get the VLAN membership table
  • OID . to get the management domain table
  • OID . to get the vtp VLAN table
  • OID . to get the VLAN trunk port information.

Model objects created

The sensor creates the following model objects:

  • net.L2Interface
  • net.Vlan
  • net.VlanInterface
  • sys.UnitaryComputerSystem