235Step Command Remarks2. Enter Ethernet interfaceview or port group view.• Enter Layer 2/Layer 3 Ethernet interfaceview:interface interface-type interface-number• Enter port group view:port-group manual port-group-nameUse either command.3. Set the encapsulationformat for LLDPDUs toSNAP.lldp encapsulation snap Ethernet II encapsulationformat applies by default.NOTE:LLDP-CDP (Cisco Discovery Protocol) packets use only SNAP encapsulation.Configuring CDP compatibilityWhen the switch is directly connected to a Cisco device that supports only CDP rather than LLDP, you canenable CDP compatibility to enable the switch to exchange information with the directly-connecteddevice.With CDP compatibility enabled on the switch, the switch can use LLDP to receive and recognize the CDPpackets received from the directly-connected device and send CDP packets to the directly-connecteddevice. The packets that the switch sends to the neighboring CDP device carry the fields in Table 27.Table 27 Fields in CDP packetsField DescriptionDevice ID Device ID, which is the bridge MAC address of the device.AddressesIPv4 address of the interface.The port IPv4 address is the main IP address of the VLAN interface that is in upstate and whose corresponding VLAN ID is the lowest among the VLANspermitted on the port. If none of the VLAN interfaces of the permitted VLANs isassigned an IP address or all VLAN interfaces are down, no port IP address willbe advertised.Port ID Port ID.Capabilities Device capability, which is Switch.Software Version Software version of the device.Platform Device model.Duplex Duplex mode of the port.MTU Maximum transmit unit.System Name System name.Native VLAN PVID of a port.Voice VLAN VLAN specified by using the lldp voice-vlan command or the voice VLANconfigured on the port.The CDP neighbor-information-related fields in the output of the display lldp neighbor-informationcommand show the CDP neighboring device information that can be recognized by the switch. For more
