Link Layer Discovery Protocol

This section describes Link Layer Discovery Protocol (LLDP) configuration tasks. Refer to the command descriptions for information about commands used in this chapter.

Topics in this section include:

LLDP Introduction

Link Layer Discovery Protocol (LLDP) lets Ethernet network devices to advertise details about themselves, such as capabilities, identification, and device configurations to directly connected devices on the network that are also using LLDP.

LLDP Overview

LLDP is a discovery protocol that allows devices to advertise information about themselves to peer devices that are on the same physical LAN and store information about the network. LLDP allows a device to learn higher layer management reachability and connection endpoint information from adjacent devices.

Each switch with an active LLDP agent sends and receives messages on all physical interfaces enabled for LLDP transmission. These messages are sent periodically and are typically configured for short time intervals to ensure that accurate information is always available. These messages are then stored for a configurable period of time, and contained within the received packet. The message information expires and is discarded when the configured value is met. The only other time an advertisement is sent is when a relevant change takes place in the switch. If information changes for any reason, the LLDP agent is notified and sends out and update the new values.

LLDP Data Units

A single LLDP Data Unit (LLDPDU) is transmitted in a single 802.3 Ethernet frame. The basic LLDPDU includes a header and a series of Type-Length-Value elements (TLVs). Each TLV advertises different types of information, such as its device ID, type, or management addresses.

LLDP advertises the following TLVs by default:
  • port-description
  • system-capabilities
  • system-description
  • system-name
  • management-address
  • port-vlan

Transmission and Reception

Every device that uses LLDP has its own LLDP agent. The LLDP agent is responsible for the reception, transmission, and management of LLDP. When LLDP is enabled on a port, transmission and reception of LLDPDUs are both enabled by default, but the agent can be configured to only transmit or only receive.

Transmission

When LLDP transmission is enabled, the LLDP agent advertises information about the switch to neighbors at regular intervals. Each transmitted LLDPDU contains the mandatory TLVs, and any enabled optional TLVs.

Reception

When LLDP reception is enabled, the LLDP agent receives and stores advertised information from neighboring devices.

Storing LLDP Information

Whenever the switch receives a valid and current LLDP advertisement from a neighbor, it stores the information in a Simple Network Management Protocol (SNMP) Management Information Base (MIB).

Guidelines and Limitations

LLDP has the following configuration limitations:
  • LLDP must be enabled globally before it can be enabled on an interface.
  • LLDP is not supported on virtual interfaces.
  • LLDP can discover only one device per port.

LLDP configuration procedures

These sections describe the following configuration processes:

Enabling LLDP Globally

The lldp run command globally enables LLDP on the Arista switch. Once LLDP is enabled, the switch will transmit advertisements from the ports that are configured to send TLVs. The neighbor information table is populated as advertisements from the neighbors arrive on the ports.

Example

This command enables LLDP globally on the Arista switch.

switch(config)# lldp run
switch(config)#

Enabling LLDP on an Interface

When enabling LLDP, it is enabled on all interfaces by default. By using the lldp transmit and lldp receive commands, LLDP can be enabled or disabled on individual interfaces or configured to only send or only receive LLDP packets.

Example

  • These commands enable interface ethernet port 3/1 to transmit LLDP packets.

    switch(config)# interface ethernet 3/1
switch(config-if-Et3/1)# lldp transmit
switch(config-if-Et3/1)#

  • These commands enable interface ethernet port 3/1 to receive LLDP packets.

    switch(config)# interface ethernet 3/1
switch(config-if-Et3/1)# lldp receive 
switch(config-if-Et3/1)#

Optional LLDP Parameters

The following sections describe these tasks:

Setting the LLDP Timer

The lldp timer command specifies the time in seconds between LLDP updates sent by the switch.

Examples
  • This command specifies that the LLDP updates should be sent every 120 seconds.
    switch(config)# lldp timer 120
switch(config)#

  • This command reverts the LLDP timer to its default value of 30 seconds.

    switch(config)# no lldp timer 120
switch(config)#

Setting the LLDP Hold Time

The lldp hold-time command sets the amount of time a receiving device should retain the information sent by the device.

Examples
  • This command specifies that the receiving device should retain the information for 180 seconds before discarding it.
    switch(config)# lldp hold-time 180
switch(config)#
  • This command reverts the LLDP hold time and to the default value of 120 seconds.
    switch(config)# no lldp hold-time 180
switch(config)#

Setting the LLDP Re-initialization Timer

The lldp run command specifies the amount in time in seconds to delay the re-initialization attempt by the switch.

Example

This command specifies that the switch waits 10 seconds before attempting to re-initialize.
switch(config)# lldp timer reinitialization 10
switch(config)#

Setting the IP Management Address to be used in the TLV

The lldp management-address command specifies the IP management address or the IP address of the VRF interface in LLDP Type-Length-Value (TLV) triplets.

Example

This command specifies the IP management address to be used in the TLV.
switch(config)# lldp management-address ethernet 3/1
switch(config)#

Selecting the LLDP TLVs

The lldp tlv transmit command specifies which Type, Length, and Value elements (TLVs) are to be included in LLDP packets. The no lldp tlv transmit command removes the TLV configuration.

Example

This command enables the system descriptions to be included in the TLVs.
switch(config)# lldp tlv transmit system-description
switch(config)#

Configuring LLDP for Power over Ethernet

Initial Power over Ethernet (PoE) power-level negotiation with a Powered Device (PD) takes place in hardware (see Configuring Power over Ethernet (PoE)). Once hardware negotiation has taken place, IEEE 802.3at Power Via MDI Type-Length-Value elements (TLVs) are included by default in LLDP packets sent to connected PDs to allow LLDP to further negotiate power needs. LLDP allows the switch to deal with more granular power requests from PDs, and also allows dynamic power-level setting. TLVs received from connected Power-Sourcing Equipment (PSE) are ignored.

Note: Power Via MDI TLVs are not sent (even when enabled) under the following circumstances:
  1. there is a user-configured power limit on the port, or
  2. hardware negotiation sets the power to higher than class 4 because IEEE 802.3bt, which increases the maximum power output for PoE, is not yet supported by LLDP.

To disable Power Via MDI TLVs globally, use the no lldp tlv transmit command and specify the Power Via MDI TLV. Hardware negotiation and manual power limits will remain in effect.

Example

This command disables the sending of Power Via MDI TLVs globally.
switch(config)# no lldp tlv transmit power-via-mdi
switch(config)#

To disable Power Via MDI TLVs on an individual interface, use the poe negotiation lldp disabled command. Hardware negotiation and manual power limits will remain in effect.

Example

These commands disable the sending of Power Via MDI TLVs on interface ethernet 5.
switch(config)# interface ethernet 5
switch(config-if-Et5)# poe negotiation lldp disabled
switch(config-if-Et5)#
New LLDP Fields Defined by IEEE 802.3at-2009
Arista switches do not support the following new LLDP/SNMP fields defined in IEEE standard 802.3at-2009:
  • Power type a LldpXdot3RemPowerType
  • Power source a LldpXdot3RemPowerSource
  • Power priority a LldpXdot3RemPowerPriority
  • PD requested power value a LldpXdot3RemPDRequestedPowerValue
  • PSE allocated power value a LldpXdot3RemPSEAllocatedPowerValue

Displaying LLDP Information

Viewing LLDP Global Information

The show lldp command displays LLDP information.

Examples
  • This command displays global information about LLDP.
    switch# show lldp
LLDP transmit interval      : 60 seconds
LLDP transmit holdtime      : 120 seconds
LLDP reinitialization delay : 2 seconds
LLDP Management Address VRF : default
Enabled optional TLVs:
  port Description
  System Name
  System Description
  System Capabilities
  Management Address (Management0)
  IEEE802.1 port VLAN ID
  IEEE802.3 Link Aggregation
  IEEE802.3 Maximum Frame Size
port       Tx Enabled  Rx Enabled
Et3/1      Yes         Yes

switch#
  • This command displays LLDP information.
    switch# show lldp ethernet interface 3/1
LLDP transmit interval      : 30 seconds
LLDP transmit holdtime      : 120 seconds
LLDP reinitialization delay : 2 seconds
LLDP Management Address VRF : default
Enabled optional TLVs:
  port Description
  System Name
  System Description
  System Capabilities
switch#

Viewing LLDP Local Information

The show lldp local-info command displays the information contained in the LLDP TLVs to be sent about the local system.

Example

This command displays information contained in the TLVS about the local systems.
switch# show lldp local-info management 1   
Local System:
  - Chassis ID type: MAC address (4)
    Chassis ID     : 001c.730f.11a8
  - System Name: "switch.aristanetworks.com"
  - System Description: "Arista Networks eos version 4.13.2F running on an Arista 
Networks DCS-7150S-64-CL"
  - System Capabilities : Bridge, Router
    Enabled Capabilities: Bridge

Interface Management1:
  - port ID type: Interface name (5)
    port ID     : "Management1"
  - port Description: ""
  - Management Address Subtype: IPv4 (1)
    Management Address        : 172.22.30.154
    Interface Number Subtype  : ifIndex (2)
    Interface Number          : 999001
    OID String                :
  - IEEE802.1 port VLAN ID: 0
  - IEEE802.1/IEEE802.3 Link Aggregation
    Link Aggregation Status: Not Capable (0x00)
    port ID                : 0
  - IEEE802.3 Maximum Frame Size: 1518 bytes
switch(config)#

Viewing LLDP Neighbors

The show lldp neighbors command displays information about LLDP neighbors.

Examples
  • This command shows information about LLDP neighbors.
    switch# show lldp neighbor
Last table change time   : 0:12:33 ago
Number of table inserts  : 33
Number of table deletes  : 0
Number of table drops    : 0
Number of table age-outs : 0

port      Neighbor Device ID             Neighbor port ID           TTL
Et3/1     tg104.sjc.aristanetworks.com   Ethernet3/2                120

Ma1/1     dc1-rack11-tor1.sjc            1/1                        120
switch#
  • This command displays detailed information about the neighbor ethernet 3/1.
    switch# show lldp neighbor ethernet 3/1
Last table change time   : 0:16:24 ago
Number of table inserts  : 33
Number of table deletes  : 0
Number of table drops    : 0
Number of table age-outs : 0

port      Neighbor Device ID             Neighbor port ID           TTL
Et3/1     tg104.sjc.aristanetworks.com   Ethernet3/2                120
switch#

Viewing LLDP Traffic

The show lldp counters command displays the LLDP traffic information for the switch.

Example

This command displays the LLDP counters on the switch.
switch# show lldp counters
port          Tx Frames Tx Length Exceeded

Et20              69485                  0
Et21              69394                  0
Et22              69203                  0
Et23              57546                  0
Et24                  0                  0
Ma1               69665                  0
port      Rx Frames     Rx Errors    Rx Discard  TLVs Discard  TLVs Unknown

Et20          69470             0             0             0             0
Et21          69383             0             0             0             0
Et22          69143             0             0             0             0
Et23          55370             0             0             0             0
Et24              0             0             0             0             0
Ma1           69078         69078             0         69078             0
switch#

LLDP configuration Commands

Global configuration Commands

Interface configuration Commands – Ethernet Interface

Privileged EXEC Commands

EXEC Commands

clear lldp counters

The clear lldp counters command resets the LLDP counters to zero.

Command Mode

Privileged EXEC

Command Syntax

clear lldp counters [SCOPE]

Parameters

SCOPE Session affected by command. Options include:
  • no parameter command affects counters on all CLI sessions.
  • session clears LLDP counters for the current CLI session only.
Examples
  • This command resets all the LLDP counters to zero.
    switch(config)# clear lldp counters
switch(config)#
  • This command resets only the LLDP counters for the current CLI session.
    switch(config)# clear lldp counters session
switch(config)#

clear lldp table

The clear lldp table command clears neighbor information from the LLDP table.

Command Mode

Privileged EXEC

Command Syntax

clear lldp table

Example
This command clears neighbor information from the LLDP table.
switch(config)# clear lldp table
switch(config)#

lldp hold-time

The lldp hold-time command specifies the amount of time a receiving device should maintain the information sent by the device before discarding it.

Command Mode

Global configuration

Command Syntax

lldp hold-time period

no lldp hold-time

default lldp hold-time

Parameters

period     The amount of time a receiving device should hold LLDPDU information before discarding it. Value ranges from 10 to 65535 second; default value is 120 seconds.

Examples
  • This command sets the amount of time before the receiving device discards LLDPDU information to 180 seconds. 
    switch(config)# lldp hold-time 180
switch(config)#
  • This command restores the hold-time to its default value of 120 seconds.
    switch(config)# no lldp hold-time 180
switch(config)#

lldp management-address

The lldp management-address command enables the user to add the IP management address used for LLDP Type-Length-Value (TLV).

Command Mode

Global configuration

Command Syntax

lldp management-address [INTERFACE]

no lldp management-address [INTERFACE]

default lldp management-address [INTERFACE]

Parameters

INTERFACE Interface type and number. Options include:
  • all     all interfaces.
  • ethernet e_num     Ethernet interface specified by e_num.
  • loopback l_num     Loopback interface specified by l_num.
  • management m_num     Management interface specified by m_num.
  • port-channel p_num     port-channel Interface specified by p_num.
  • vlan v_num     VLAN interface specified by v_num.
Examples
  • This command specifies the IP management address to be used in the TLV.
    switch(config)# lldp management-address ethernet 3/1
switch(config)#
  • This command removes the IP management address used in the TLV.
    switch(config)# no lldp management-address ethernet 3/1
switch(config)#
  • This command specifies that vlan200 is used in the TLV.
    switch(config)# lldp management-address vlan 200
switch(config)#
  • This command removes the VLAN ID used in the TLV.
    switch(config)# no lldp management-address vlan 200
switch(config)#

lldp management-address vrf

The lldp management-address vrf command enables the user to add the IP address of the VRF interface used in LLDP Type-Length-Value (TLV).

Command Mode

Global configuration

Command Syntax

lldp management-address vrf VRF_INSTANCE

no lldp management-address vrf VRF_INSTANCE

default lldp management-address vrf VRF_INSTANCE

Parameters

VRF_INSTANCE     specifies the VRF instance.

Examples
  • This command specifies the management address VRF to be used in the TLV.
    switch(config)# lldp management-address vrf test 1
switch(config)#
  • This command removes the management VRF used in the TLV.
    switch(config)# no lldp management-address vrf test 1
switch(config)#

lldp receive

The lldp receive command enables LLDP packets on an interface. The no lldp receive command disables the acceptance of LLDP packets.

Command Mode

Interface-Ethernet configuration

Interface-Management configuration

Command Syntax

lldp receive

no lldp receive

default lldp receive

Examples
  • These commands enable the reception of LLDP packets on interface ethernet 4/1.
    switch(config)# interface ethernet 4/1
switch(config-if-Et4/1)# lldp receive
switch(config-if-Et4/1)#
  • These commands disable LLDP the reception of LLDP packets on interface ethernet 4/1.
    switch(config)# interface ethernet 4/1
switch(config-if-Et4/1)# no lldp receive
switch(config-if-Et4/1)#

lldp receive packet tagged drop

The lldp receive packet tagged drop command is a global configuration command and when configured the LLDP ignores all the packets with VLAN-tag. By default, this command is disabled.

Command Mode

Global configuration

Command Syntax

lldp receive packet tagged drop

Example

This command when configured, the LLDP ignores all the packets with VLAN-tag.
switch(config)# lldp receive packet tagged drop

lldp run

The lldp run command enables LLDP on the switch.

Command Mode

Global configuration

Command Syntax

lldp run

no lldp run

default lldp run

Examples
  • This command enables LLDP globally on the switch.
    switch(config)# lldp run
switch(config)#
  • This command disables LLDP globally on the switch.
    switch(config)# no lldp run
switch(config)#

lldp timer reinitialization

The lldp timer reinitialization command sets the time delay in seconds for LLDP to initialize.

Command Mode

Global configuration

Command Syntax

lldp timer reinitialization delay

no lldp timer reinitialization

default lldp timer reinitialization

Parameters

delay the amount of time the device should wait before re-initialization is attempted. Value ranges from 1 to 20 seconds; default value is 2 seconds.

Examples
  • This command specifies that the switch should wait 10 seconds before attempting to re-initialize.
    switch(config)# lldp timer reinitialization 10
switch(config)#
  • This command restores the default initialization delay of 2 seconds.
    switch(config)# no lldp timer reinitialization 10
switch(config)#

lldp timer

The lldp timer command specifies the amount of time a receiving device should maintain the information sent by the device before discarding it. The no lldp timer command removes the configured LLDP timer.

Command Mode

Global configuration

Command Syntax

lldp timer transmission_time

no lldp timer

default lldp timer

Parameters

transmission_time the period of time at which LLDPDUs are transmitted. Values range from 5 to 32768 seconds; the default is 30 seconds.

Examples
  • This command configures a period of 180 seconds at which the LLDPDUs are transmitted.
    switch(config)# lldp timer 180
switch(config)#
  • This command removes the configured period of time at which the LLDPDUs are transmitted.
    switch(config)# no lldp timer 180
switch(config)#

lldp tlv transmit

The lldp tlv transmit command allows the user to specify the Type-Length-Values (TLVs) to include in LLDP packets.

Command Mode

Global configuration

Command Syntax

lldp tlv transmit TLV_NAME

no lldp tlv transmit TLV_NAM

default lldp tlv transmit TLV_NAME

Parameters

TLV_NAME Options include:
  • link-aggregation specifies the link aggregation TLV.
  • management-address specifies the management address TLV.
  • max-frame-size specifies the Frame size TLV.
  • port-description specifies the port description TLV.
  • port-vlan specifies the port VLAN ID TLV.
  • power-via-mdi specifies the power over Ethernet TLV.
  • system-capabilities specifies the system capabilities TLV.
  • system-description specifies the system description TLV.
  • system-name specifies the system name TLV.
Examples
  • This command enables the system description TLV: 
    switch(config)# lldp tlv transmit system-description
switch(config)#
  • This command disables the system description TLV:
    switch(config)# no lldp tlv transmit system-description
switch(config)#

  • This command enables the max-frame-size TLV: 

    switch(config)# lldp tlv transmit max-frame-size
switch(config)#

  • This command disables the max-frame-size TLV:

    switch(config)# no lldp tlv transmit max-frame-size
switch(config)#

lldp transmit

The lldp transmit command enables the transit of LLDP packets on an interface.

Command Mode

Interface-Ethernet configuration

Interface-Management configuration

Command Syntax

lldp transmit

no lldp transmit

default lldp transmit

Examples
  • These commands enable the transmission of LLDP packets.
    switch(config)# interface ethernet 4/1
switch(config-if-Et4/1)# lldp transmit
switch(config-if-Et4/1)#
  • These commands disable the transmission of LLDP packets.
    switch(config)# interface ethernet 4/1
switch(config-if-Et4/1)# no lldp transmit
switch(config-if-Et4/1)#

poe negotiation lldp disabled

Power Via MDI TLVs are included by default in LLDP packets sent to Power over Ethernet (PoE) Powered Devices (PDs) to allow dynamic negotiation of power levels. The poe negotiation lldp disabled command disables the sending of Power Via MDI TLVs from the configuration-mode interface.

The no poe negotiation lldp disabled and default poe negotiation lldp disabled commands restore the default behavior (sending Power Via MDI TLVs) by removing the corresponding poe negotiation lldp disabled command from running-config.

To disable Power Via MDI TLVs globally, use the no lldp tlv transmit command and specify the Power Via MDI TLV.

Command Mode

Interface-Ethernet configuration

Command Syntax

poe negotiation lldp disabled

no poe negotiation lldp disabled

default poe negotiation lldp disabled

Example

These commands disable the sending of power via MDI TLVs on interface ethernet 5.
switch(config)# interface ethernet 5
switch(config-if-Et5)# poe negotiation lldp disabled
switch(config-if-Et5)#

show lldp counters

The show lldp counters command displays LLDP traffic information for the switch.

Command Mode

EXEC

Command Syntax

show lldp counters [INTERFACE]

Parameters

INTERFACE     Interface type and numbers. Options include:
  • no parameter     Display information for all interfaces.
  • ethernet e_range     Ethernet interface range specified by e_range.
  • management m_range Management interface range specified by m_range.

    Valid e_range and m_range formats include number, number range, or comma-delimited list of numbers and ranges.

Example

This command displays the LLDP counters on the switch.
switch# show lldp counters 

port          Tx Frames Tx Length Exceeded

Et20              69485                  0
Et21              69394                  0
Et22              69203                  0
Et23              57546                  0
Et24                  0                  0
Ma1               69665                  0

port          Rx Frames     Rx Errors    Rx Discard  TLVs Discard  TLVs Unknown

Et20              69470             0             0             0             0
Et21              69383             0             0             0             0
Et22              69143             0             0             0             0
Et23              55370             0             0             0             0
Et24                  0             0             0             0             0
Ma1               69078         69078             0         69078             0

show lldp local-info

The show lldp local-info command displays LLDP errors and overflows.

Command Mode

EXEC

Command Syntax

show lldp local-info [INTERFACE]

Parameters

INTERFACE     Interface type and numbers. Options include:
  • no parameter     Display information for all interfaces.
  • ethernet e_range     Ethernet interface range specified by e_range.
  • management m_range Management interface range specified by m_range.

    Valid e_range and m_range formats include number, number range, or comma-delimited list of numbers and ranges.

Example

This command displays the specific LLDP errors and overflows on management interface 1.
switch# show lldp local-info management 1
Local System:
  - Chassis ID type: MAC address (4)
    Chassis ID     : 001c.730f.11a8qqq
  - System Name: "switch.aristanetworks.com"
  - System Description: "Arista Networks eos version 4.13.2F running on an Arista 
Networks DCS-7150S-64-CL"
  - System Capabilities : Bridge, Router
    Enabled Capabilities: Bridge

Interface Management1:
  - port ID type: Interface name (5)
    port ID     : "Management1"
  - port Description: ""
  - Management Address Subtype: IPv4 (1)
    Management Address        : 172.22.30.154
    Interface Number Subtype  : ifIndex (2)
    Interface Number          : 999001
    OID String                :
  - IEEE802.1 port VLAN ID: 0
  - IEEE802.1/IEEE802.3 Link Aggregation
    Link Aggregation Status: Not Capable (0x00)
    port ID                : 0
  - IEEE802.3 Maximum Frame Size: 1518 bytes
se505.16:01:44#
switch#

show lldp neighbors

The show llpd neighbors command displays information about the switch’s LLDP neighbors.

Command Mode

EXEC

Command Syntax

show lldp neighbors [INTERFACE][INFO_LEVEL]

Parameters
  • INTERFACE     Interface type and numbers. Options include:
    • no parameter     displays information for all interfaces.
    • ethernet e_range     Ethernet interface range specified by e_range.
    • management m_range Management interface range specified by m_range.
    • Valid e_range and m_range formats include number, number range, or comma-delimited list of numbers and ranges.
  • INFO_LEVEL     amount of information that is displayed. Options include:
    • no parameter     Displays information for all interfaces.
    • detailed     LLDP information for all the adjacent LLDP devices.
Examples
  • This command displays the neighbor’s information about LLDP.
    switch(config)# show lldp neighbors
Last table change time   : 0:12:33 ago
Number of table inserts  : 33
Number of table deletes  : 0
Number of table drops    : 0
Number of table age-outs : 0

port      Neighbor Device ID             Neighbor port ID      TTL
Et3/1     tg104.sjc.aristanetworks.com   Ethernet3/2           120

Ma1/1     dc1-rack11-tor1.sjc            1/1                   120
switch#
  • This command displays LLDP neighbor information for interface ethernet 3/1.
    switch# show lldp neighbors ethernet 3/1              
Last table change time   : 0:16:24 ago
Number of table inserts  : 33
Number of table deletes  : 0
Number of table drops    : 0
Number of table age-outs : 0

port      Neighbor Device ID             Neighbor port ID       TTL
Et3/1     tg104.sjc.aristanetworks.com   Ethernet3/2            120
switch#
  • This command displays detailed LLDP neighbor information for interface ethernet 3/1.
    switch# show lldp neighbors 3/1 detail

Interface Ethernet 3/1 detected 1 LLDP neighbors:

  Neighbor 001c.7300.1506/Ethernet6/25, age 8 seconds
  Discovered 5 days, 3:58:58 ago; Last changed 5 days, 3:56:57 ago
    - Chassis ID type: MAC address (4)
      Chassis ID     : 001c.7300.1506
    - port ID type: Interface name (5)
      port ID     : "Ethernet6/25"
    - Time To Live: 120 seconds
 - port Description: "Ethernet6/25"
 - IEEE802.3 Power Via MDI
    port Class               : PD
    PSE MDI Power Support    : Not Supported
    PSE MDI Power State      : Disabled
    - System Name: "Leaf-Switch1.aristanetworks.com"
    - System Description: "Arista Networks eos version 4.10.1-SSO running on an Arista Networks DCS-7504"
    - System Capabilities : Bridge, Router
      Enabled Capabilities: Bridge
    - Management Address Subtype: IPv4 (1)
      Management Address        : 172.22.30.116
      Interface Number Subtype  : ifIndex (2)
      Interface Number          : 999999
      OID String                :
    - IEEE802.1 port VLAN ID: 1
    - IEEE802.1/IEEE802.3 Link Aggregation
      Link Aggregation Status: Capable, Disabled (0x01)
      port ID                : 0
    - IEEE802.3 Maximum Frame Size: 9236 bytes
switch#

show lldp

The show lldp command displays LLDP information.

Command Mode

EXEC

Command Syntax

show lldp [INTERFACE]

Parameters

INTERFACE     Interface type and numbers. Options include:
  • no parameter     Display information for all interfaces.
  • ethernet e_range     Ethernet interface range specified by e_range.
  • management m_range Management interface range specified by m_range.

    Valid e_range and m_range formats include number, number range, or comma-delimited list of numbers and ranges.

Examples
  • This command displays all LLDP information.
    switch# show lldp 
LLDP transmit interval      : 60 seconds
LLDP transmit holdtime      : 120 seconds
LLDP reinitialization delay : 2 seconds
LLDP Management Address VRF : test

Enabled optional TLVs:
  port Description
  System Name
  System Description
  System Capabilities
  Management Address (Management0)
  IEEE802.1 port VLAN ID
  IEEE802.3 Link Aggregation
  IEEE802.3 Maximum Frame Size

port       Tx Enabled  Rx Enabled
Et3/1      Yes         Yes

switch#
  • This command displays specific information about LLDP for interface ethernet 3/1.
    switch# show lldp ethernet 3/1
LLDP transmit interval      : 30 seconds
LLDP transmit holdtime      : 120 seconds
LLDP reinitialization delay : 2 seconds
LLDP Management Address VRF : default

Enabled optional TLVs:
  port Description
  System Name
  System Description
  System Capabilities
switch#
  • This command displays specific information about LLDP for management interface 1/1.
    switch# show lldp management 1/1
LLDP transmit interval      : 60 seconds
LLDP transmit holdtime      : 120 seconds
LLDP reinitialization delay : 2 seconds
LLDP Management Address VRF : default

Enabled optional TLVs:
  port Description
  System Name
  System Description
  System Capabilities
  Management Address (Management0)
  IEEE802.1 port VLAN ID
  IEEE802.3 Link Aggregation
  IEEE802.3 Maximum Frame Size

port       Tx Enabled  Rx Enabled
Ma1/1      Yes         Yes
switch#