Add LLDP to Services chapter

docs/services.rst

@@ -793,6 +793,102 @@ ddclient_ will load the webpage at `[url]` and will try to extract an IP
 address for the response. ddclient_ will skip any address located before the
 string set in `[skip]`.
 
+LLDP
+----
+
+The Link Layer Discovery Protocol (LLDP) 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.[1] 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:: sh
+
+  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 operationnal command ``show log lldp`` to display logs.
+
 mDNS Repeater
 -------------
 
@@ -1096,6 +1192,8 @@ The resulting configuration will look like:
 
 .. _ddclient: http://sourceforge.net/p/ddclient/wiki/Home/
 .. _RFC2136: https://www.ietf.org/rfc/rfc2136.txt
+.. _`Cisco Discovery Protocol`: https://en.wikipedia.org/wiki/Cisco_Discovery_Protocol
+.. _`Foundry Discovery Protocol`: https://en.wikipedia.org/wiki/Foundry_Discovery_Protocol
 .. _`Multicast DNS`: https://en.wikipedia.org/wiki/Multicast_DNS
 .. _SNMP: https://en.wikipedia.org/wiki/Simple_Network_Management_Protocol
 .. _SNMPv2: https://en.wikipedia.org/wiki/Simple_Network_Management_Protocol#Version_2