Receiving LLDP Messages

You can configure each port to transmit LLDP messages, receive LLDP messages, or both.

After you configure a port to receive TLVs, all LLDP TLVs are received (even if the LLDP MED capabilities TLV is not enabled). Each port can store LLDP information for a maximum of four neighbors.

Note

When both IEEE 802.1X and LLDP are enabled on the same port, incoming LLDP packets are accepted only when one or more clients are authenticated.

When configured to receive LLDP messages, the TLVs received at a port are stored in a standard Management Information Base (MIB), which makes it possible for the information to be accessed by an SNMP-compatible NMS. Unrecognized TLVs are also stored on the switch, in order of TLV type. TLV information is purged after the configured timeout interval, unless it is refreshed by the remote LLDP agent. You can also manually clear the LLDP information for one or all ports with the clear lldp neighbors command.