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a different power value using the max-milliwatts option with the power inline auto | static command. Dell
Networking also honors the power value (power requirement) the powered device sends when the port is configured for
power inline auto.
Figure 72. Extended Power via MDI TLV
LLDP Operation
On an Aggregator, LLDP operates as follows:
● LLDP is enabled by default.
● LLDPDUs are transmitted and received by default. LLDPDUs are transmitted periodically. The default interval is 30 seconds.
● LLDPDU information received from a neighbor expires after the default Time to Live (TTL) value: 120 seconds.
● Dell Networking OS supports up to eight neighbors per interface.
● Dell Networking OS supports a maximum of 8000 total neighbors per system. If the number of interfaces multiplied by eight
exceeds the maximum, the system does not configure more than 8000.
● LLDP is not hitless.
Storing and Viewing Unrecognized LLDP TLVs
Dell EMC Networking OS provides support to store unrecognized (reserved and organizational specific) 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 specific 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
first unrecognized TLV is stored and the TLV discard counter is incremented for the successive TLVs.
Organizational Specific Unrecognized LLDP TLVs
The type value for organizational specific TLV is 127.
The system processes each LLDP frame to retrieve the OUI, subtype, and data length, and stores the retrieved data of
organizational specific 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 identification index for each unrecognized organizational specific
LLDP TLVs upon receiving more than one TLV with the same OUI and subtype, but with different organizationally defined
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
454 Link Layer Discovery Protocol (LLDP)