.. _lldp:

LLDP
----

:abbr:`LLDP (Link Layer Discovery Protocol)` is a vendor-neutral link layer
protocol in the Internet Protocol Suite used by network devices for advertising
their identity, capabilities, and neighbors on an IEEE 802 local area network,
principally wired Ethernet. The protocol is formally referred to by the IEEE
as Station and Media Access Control Connectivity Discovery specified in IEEE
802.1AB and IEEE 802.3-2012 section 6 clause 79.

LLDP performs functions similar to several proprietary protocols, such as
`Cisco Discovery Protocol`_, `Foundry Discovery Protocol`_,
Nortel Discovery Protocol and Link Layer Topology Discovery.

Information gathered
^^^^^^^^^^^^^^^^^^^^

Information gathered with LLDP is stored in the device as a management
information database (MIB_) and can be queried with the Simple Network
Management Protocol (SNMP_) as specified in :rfc:`2922`. The topology of an
LLDP-enabled network can be discovered by crawling the hosts and querying this
database. Information that may be retrieved include:

* System name and description
* Port name and description
* VLAN name
* IP management address
* System capabilities (switching, routing, etc.)
* MAC/PHY information
* MDI power
* Link aggregation

Configuration
^^^^^^^^^^^^^

* Enable service with:

  :code:`set service lldp`

Options
*******

* Configure a Define management-address:

  :code:`set service lldp management-address <x.x.x.x>`

* Define listening interfaces

  :code:`set service lldp interface <all|interface name>`

* LLDPd also implements an SNMP subagent. To Enable SNMP queries of the LLDP
  database:

  :code:`set service lldp snmp enable`

* Enable optional/other protocols

  :code:`set service lldp legacy-protocols cdp`

  Supported legacy protocols:

 * ``cdp`` - Listen for CDP for Cisco routers/switches
 * ``edp`` - Listen for EDP for Extreme routers/switches
 * ``fdp`` - Listen for FDP for Foundry routers/switches
 * ``sonmp`` - Listen for SONMP for Nortel routers/switches


Display neighbors
^^^^^^^^^^^^^^^^^

* Display with:

``show lldp neighbors``

Exemple:

.. code-block:: none

  vyos@vyos:~# show lldp neighbors
  Capability Codes: R - Router, B - Bridge, W - Wlan r - Repeater, S - Station
                   D - Docsis, T - Telephone, O - Other
  Device ID                 Local  Proto  Cap   Platform             Port ID
  ---------                 -----  -----  ---   --------             -------
  swA309                    eth0   LLDP   ?     Cisco IOS Software,  GigE0/33


* Options:

 * ``detail`` - Show lldp neighbors detail
 * ``interface`` - Show LLDP for specified interface

Troubleshooting
^^^^^^^^^^^^^^^

Use operational command ``show log lldp`` to display logs.

.. include:: references.rst