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Link Layer Discovery Protocol (LLDP)
Link layer discovery protocol (LLDP) advertises connectivity and management from the local station to the adjacent stations on
an IEEE 802 LAN.
LLDP facilitates multi-vendor interoperability by using standard management tools to discover and make available a physical
topology for network management. The Dell Networking operating software implementation of LLDP is based on IEEE standard
801.1ab.
The starting point for using LLDP is invoking LLDP with the protocol lldp command in either CONFIGURATION or INTERFACE
mode.
The information LLDP distributes is stored by its recipients in a standard management information base (MIB). You can access
the information by a network management system through a management protocol such as simple network management
protocol (SNMP).
An Aggregator auto-configures to support the link layer discovery protocol (LLDP) for the auto-discovery of network devices.
You can use CLI commands to display acquired LLDP information, clear LLDP counters, and debug LACP operation.
Supported Modes
Standalone, PMUX, VLT, Stacking
Topics:
• Protocol Data Units
• Configure LLDP
• CONFIGURATION versus INTERFACE Configurations
• Enabling LLDP
• Advertising TLVs
• Optional TLVs
• LLDP Operation
• Storing and Viewing Unrecognized LLDP TLVs
• Viewing the LLDP Configuration
• Viewing Information Advertised by Adjacent LLDP Agents
• Configuring LLDPDU Intervals
• Configuring a Time to Live
• Clearing LLDP Counters
• Debugging LLDP
• Relevant Management Objects
Protocol Data Units
Configuration information is exchanged in the form of type, length, value (TLV) segments. The below figure shows the chassis
ID TLV.
● Type — Indicates the type of field that a part of the message represents.
● Length — Indicates the size of the value field (in byte).
● Value — Indicates the data for this part of the message.
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