lldpd daemon implements the IEEE802.1AB (Link Layer Discovery Protocol, or LLDP) standard. LLDP enables you to know which ports are neighbors of a given port. By default,
lldpd runs as a daemon and is started at system boot.
lldpd command line arguments are placed in
lldpd configuration options are placed in
/etc/lldpd.conf or under
For more details on the command line arguments and config options, see
lldpd supports CDP (Cisco Discovery Protocol, v1 and v2).
lldpd logs by default into
/var/log/daemon.log with an
lldpcli is the CLI tool to query the
lldpd daemon for neighbors, statistics, and other running configuration information. See
man lldpcli(8) for details.
lldpd settings in
Here is an example persistent configuration:
The last line in the example above shows that LLDP is disabled on eth0. You can disable LLDP on a single port by editing the
/etc/default/lldpd file. This file specifies the default options to present to the
lldpd service when it starts. The following example uses the
-I option to disable LLDP on swp43:
lldpd logs to
/var/log/daemon.log with the lldpd prefix:
Example lldpcli Commands
To show all neighbors on all ports/interfaces:
lldpd statistics for all ports:
lldpd statistics summary for all ports:
To show the
lldpd running configuration:
A runtime configuration does not persist when you reboot the switch — all changes are lost.
To configure active interfaces:
To configure inactive interfaces:
To reset any interface list to none:
Enable the SNMP Subagent in LLDP
LLDP does not enable the SNMP subagent by default. You need to edit
/etc/default/lldpd and enable the
Caveats and Errata
- Annex E (and hence Annex D) of IEEE802.1AB (lldp) is not supported.