Concept Guide

Figure 82. Conguring LLDP
Storing and Viewing Unrecognized LLDP TLVs
Dell EMC Networking OS provides support to store unrecognized (reserved and organizational specic) LLDP TLVs. Also, support is
extended to retrieve the stored unrecognized TLVs using SNMP.
When the incoming TLV from LLDP neighbors is not recognized, the TLV is categorized as unrecognized TLV. The unrecognized TLVs is
categorized into two types:
1 Reserved unrecognized LLDP TLV
2 Organizational specic unrecognized LLDP TLV
Reserved Unrecognized LLDP TLVs
The type value for reserved TLV ranging from 9 to 126.
The system processes each LLDP frame to retrieve the type and length, and stores the retrieved data of reserved unrecognized LLDP
TLVs in a list. The stored list of unrecognized TLVs is removed when subsequent LLDP neighbor frame is received, neighbor is lost, or
neighbor ages out. If there are multiple unrecognized TLVs with the same TLV type, only the information of rst unrecognized TLV is stored
and the TLV discard counter is incremented for the successive TLVs.
Organizational Specic Unrecognized LLDP TLVs
The type value for organizational specic TLV is 127.
The system processes each LLDP frame to retrieve the OUI, subtype, and data length, and stores the retrieved data of organizational
specic unrecognized LLDP TLVs in a list. The stored list of organizational TLVs is removed when the neighbor is lost or neighbor ages out.
The software assigns a temporary identication index for each unrecognized organizational specic LLDP TLVs upon receiving more than
one TLV with the same OUI and subtype, but with dierent organizationally dened information strings.
NOTE
:
The system increments the TLV discard counter and does not store unrecognized LLDP TLV information in following scenarios:
• If there are multiple TLVs with the same information is received
• If DCBX is down on the receiving interface
Link Layer Discovery Protocol (LLDP) 595