Functions of the LLDP Agent

The LLDP agent transmits as well as receives LLDP packets, which are also called protocol data units (PDUs). The agent manages and stores the information contained in these packets in two types of data stores:

• Local management information base, or local MIB. This data store contains network information that pertains to the specific link on which the LLDP agent is enabled. A local MIB contains both common and unique information. For example, the chassis ID is common information that is shared among all the LLDP agents on the system. However, port numbers are different for the system's datalinks. Thus, each agent manages its own local MIB.

• Remote MIB. Information in this data store pertains to other systems on the local network.

Configuring How the LLDP Agent Operates

The LLDP agent can be configured to operate in the following modes:

• In transmit only (txonly) mode, the agent does not process incoming LLDP packets. Therefore, the remote MIB is empty.

• In receive only (rxonly) mode, the agent processes only incoming LLDP packets and stores the information in remote MIBs. However, no information from the local MIB is being transmitted.

• In both transmit and receive (both) mode, the agent transmits as well as receives LLDP packets. Both types of MIBs are actively in use. This mode also automatically enables DCB features that are supported by the underlying link.

• In disabled (disable) mode, the agent does not exist.

How to Enable LLDP

This procedure enables LLDP on your system for the first time.

1. Install the LLDP package.

   # pkg install lldp

   ---

   Note - For an overview about Oracle Solaris packages and how to install them, see Chapter 12, Managing Software Packages (Tasks), in Oracle Solaris Administration: Common Tasks.

   ---

2. Start the LLDP service on the system.

   # svcadm enable svc:/network/lldp:default

3. Identify the datalink on which you want to enable LLDP.
4. Set the mode of operation for that datalink's LLDP agent.

   # lldpadm set-agentprop -p mode=value agent

   where value can be one of the modes of operation, and agent uses the name of the datalink on which LLDP is enabled.

   ---

   Note - The subcommands of the lldpadm command can be typed in abbreviated form to facilitate the command's use. For example, lldpadm set-agentprop can instead be typed as lldpadm set-ap. Refer to the lldpadm(1M) man page for the subcommands and their abbreviated forms.

   ---

5. To confirm the LLDP agent's mode of operation, type the following command:

   # lldpadm show-agentprop -p mode agent

6. To disable an LLDP agent, use either of the following commands:
   • lldpadm set-agentprop -p mode=disable agent
   • lldpadm reset-agentprop -p mode agent
7. To turn off LLDP in the entire system, type the following:

   # svcadm disable svc:/network/lldp:default

Example 16-1 Enabling LLDP on Multiple Datalinks

In this example, a system has two datalinks, net0 and net1, and LLDP is enabled in different modes for each LLDP agent. One agent operates by both transmitting and receiving LLDP packets while the other agent only transmits LLDP packets.

# svcadm enable svc:/network/lldp:default
# lldpadm set-agentprop -p mode=both net0
# lldpadm set-agentprop -p mode=txonly net1

Configuring What Information To Advertise

The LLDP agent transmits system and connectivity information in LLDP packets or LLDPDUs. Such packets would contain information units that are individually formatted in Type-Length-Value (TLV) format. Thus, the information units are also called TLV units. Certain TLV units are mandatory and are included in LLDP packets by default when LLDP is enabled. The mandatory TLV units are as follows:

• Chassis ID

• Port ID

• TTL (time to live)

• End of PDU

The Chassis ID is the information that is generated by the hostid command while the Port ID is the MAC address of the physical NIC. Multiple LLDP agents can be enabled in a single system depending on the number of links. The combined Chassis ID and Port ID uniquely identifies an agent and distinguishes it from other agents on the system.

You cannot use the lldpadm command to exclude any of the mandatory TLV units from LLDP packets.

Optional TLV units can be added to an LLDP packet. These optional TLV units are means for vendors to insert vendor-specific TLV units to be advertised. The TLV units are identified by individual organization unique identifiers (OUIs) and are typed according to whether these OUIs are IEEE 802.1 specifications or IEEE 802.3 specifications. LLDP agent properties that correspond to each TLV type are created so that you can set the values for each type.

The following table lists the TLV types or groups, their corresponding property names, the TLV units for each property, and their descriptions.

Table 16-1 TLV Units That Can Be Enabled for an LLDP Agent

You configure any one of these properties to specify the TLV units to be included in the packets when LLDP is enabled.

How to Specify TLV Units for LLDP Packets

This procedure shows how to add a TLV unit to be advertised in the LLDP packet. To set TLV units for LLDP packets, you use the lldpadm set-agentprop subcommand.

1. If necessary, identify the LLDP agent property that can contain the TLV unit that you want to add.

   This subcommand also displays the TLV units that are already set for each property.

   # lldpadm show-agentprop agent

   Without specifying the property, this subcommand displays all the LLDP agent properties and their TLV values.

2. Add the TLV unit to the property.

   # lldpadm set-agentprop -p property[+|-]=value[,...] agent

   The +|- qualifiers are used for properties that accept multiple values. These qualifiers enable you to add (+) or remove (-) values from the list. If you do not use the qualifiers, then the value that you set replaces all the values that were previously defined for the property.

3. (Optional) Display the new values for the property.

   # lldpadm show-agentprop -p property agent

Example 16-2 Adding Optional TLV Units to the LLDP Packet

In this example, the LLDP agent net0 is already configured to advertise VLAN information in the packet. You want to include system capabilities, link aggregation, and network virtualization information to be advertised as well. However, you want to remove the VLAN description from the packet.

# lldpadm show-agentprop net0
# lldpadm set-agentprop -p dot1-tlv+=linkaggr net0
AGENT   PROPERTY   PERM   VALUE          DEFAULT   POSSIBLE
net0    mode       rw     both           disable   txonly,rxonly,both,
                                                   disable
net0    basic-tlv  rw     sysname,        none     none,portdesc,
                          sysdesc                  sysname,sysdesc,
                                                   syscapab,mgmtaddr,
                                                   all
net0    dot1-tlv   rw     vlanname,       none     none,vlanname,pvid,
                          pvid,pfc                 linkaggr,pfc,appln,
                                                   all
net0    dot3-tlv   rw     max-framesize   none     none, max-framesize,
                                                   all
net0    virt-tlv   rw     none            none     none,vnic,all


# lldpadm set-agentprop -p basic-tlv+=syscapab,dot1-tlv+=linkaggr,virt-tlv=vnic net0
# lldpadm set-agentprop -p dot1-tlv-=pfc net0
# lldpadm show-agentprop -p net0
AGENT   PROPERTY   PERM   VALUE          DEFAULT   POSSIBLE
net0    mode       rw     both           disable   txonly,rxonly,both,
                                                   disable
net0    basic-tlv  rw     sysname,        none     none,portdesc,
                          sysdesc,                 sysname,sysdesc,
                          syscapab                 syscapab,mgmtaddr,
                                                   all
net0    dot1-tlv   rw     vlanname,       none     none,vlanname,pvid,
                          pvid,                    linkaggr,pfc,appln,
                          linkaggr                 all
net0    dot3-tlv   rw     max-framesize   none     none, max-framesize,
                                                   all
net0    virt-tlv   rw     vnic            none     none,vnic,all