Components of an LLDP Implementation

LLDP is implemented with the following components:

• The LLDP package must be installed to enable the LLDP feature. This package delivers the LLDP daemon, command-line utilities, service manifest and scripts, and other components that are required for LLDP to operate.

• The lldp service is enabled by the svcadm command. This service manages the LLDP daemon and is responsible for starting, stopping, restarting, or refreshing the daemon. The service is disabled by default. Therefore, to use LLDP, the service must first be enabled globally for the system. After the lldp service is enabled and the daemon is started, then the LLDP functionality can be enabled on individual links as determined by the system administrator.

• The lldpadm command administers LLDP on individual links and is used, for example, to configure the operating mode of LLDP, to specify Time-Length-Value (TLV) units that will be transmitted, and to configure DCB application information. Specifically, the command is used to set per-agent LLDP properties as well as global LLDP properties. The general subcommands of the lldpadm command parallel those of the dladm and ipadm commands.

  • lldpadm set-* specifies the action to be performed in which one or more values are set for a given LLDP property.

  • lldpadm show-* displays the values that are set for a specified LLDP property.

  • lldpadm reset-* returns the configuration of a specified LLDP property to its default values.

  Use of these subcommands is illustrated in subsequent sections. For more information about the lldpadm command, refer to the lldpadm(1M) man page.

• The LLDP library (liblldp.so) provides APIs that can be used to retrieve LLDP information on a link, to parse LLDP packets, and to perform other functions.

• LLDP agents are LLDP instances that are associated with the physical NICs where LLDP is enabled. An LLDP agent controls LLDP behavior on the associated NIC. LLDP agents can be configured only on physical NICs.

• The LLDP daemon (lldpd) functions as a manager of the LLDP agents on the system. It also interacts with snmpd, the daemon for the Simple Network Management Protocol (SNMP), to retrieve LLDP information that is received on the system through SNMP. In addition, the daemon posts sysevents information as well as responds to queries from the LLDP library.

The following section describes the LLDP agent in more detail.