LLDP on FortiSwitch Managed by FortiLink

By Manny Fernandez

September 8, 2026

LLDP on FortiSwitch Managed by FortiLink

Here is a quick article on running lldp on your FortiSwitch. Customer had an issue today where they could not find the IP addresses of some HP switches he had attached t0 a FortiSwitch port.

config switch-controller managed-switch
edit "<FortiSwitch-Serial-Number>"
config ports
edit "port1"
set lldp-status rx-tx
next
end
next
end

The available options for lldp-status are:

rx-tx: Transmit and receive LLDP frames (default on standard user/ISL ports).
rx-only: Only listen for LLDP neighbors.
tx-only: Only broadcast local chassis and port TLVs.
disable: Completely disable LLDP processing on the interface.

Once you have lldp configured on the port, you can use the following command to see the connected lldp devices.

diagnose switch-controller switch-info lldp neighbors-summary <FortiSwitch-Serial-Number>
diagnose switch-controller switch-info lldp neighbors-detail <FortiSwitch-Serial-Number> <port_name>

For this customer, we needed the IP address so we used the neighbor-detail command. Below is the output.

Neighbor learned on port port5 by LLDP protocol
Last change 631185 seconds ago
Last packet received 6 seconds ago

Chassis ID: 38:21:37:e2:33:40 (mac)
System Name: REM-PHX-SW003
System Description:
HP J9772A 2530-48G-PoEP Switch, revision YA.16.11.0030, ROM YA.15.20 (/ws/swbuildm/rel_beluru_qaoff/code/build/lakes(swbuildm_rel_beluru_qaoff_rel_beluru
))

Time To Live: 120 seconds
System Capabilities: B
Enabled Capabilities: B
Management IP Address: 10.1.100.13
Management IP Interface Subtype: unknown, Index: 0

Port ID: 48 (local)
Port description: 48
IEEE802.1, Port VLAN ID: 1
IEEE802.3, MAC/PHY Configuration/Status:
Autoneg support: Supported
Autoneg enabled: Enabled
Autoneg advertised: 0x6c01
1000BASE-T(full duplex mode)
100BASE-T(full duplex mode)
100BASE-T(half duplex mode)
10BASE-T(full duplex mode)
10BASE-T(half duplex mode)
MAU type: 1000BASETFD - Four-pair Category 5 UTP, full duplex mode
IEEE802.3, Power via MDI:
Power devicetype: PSE
PSE MDI Power: Supported
PSE MDI Power Enabled: Yes
PSE Pair Selection: Can not be controlled
PSE power pairs: Signal
Power class: 1 (class-0)
Power type: 802.3at off
Power source: Unknown
Power priority: Unknown
Power requested: 0.0W
Power allocated: 0.0W
Organizationally Specific TLV:
OUI: 00:16:b9
Subtype: 2
Info: (2 bytes)
[..] 0001

With the neighbor-summary command, you get a more condensed version of the output.

diagnose switch-controller switch-info lldp neighbors-summary REM-PHX--SW000
Vdom: root
Managed Switch : ATC-REM-PHX--SW

Capability codes:
R:Router, B:Bridge, T:Telephone, C:DOCSIS Cable Device
W:WLAN Access Point, P:Repeater, S:Station, O:Other
MED type codes:
Generic:Generic Endpoint (Class 1), Media:Media Endpoint (Class 2)
Comms:Communications Endpoint (Class 3), Network:Network Connectivity Device

Portname Status Device-name TTL Capability MED-type Port-ID
__________ _______ __________________________ ____ __________ ________ _______
port1 Up PHX-RT01 120 BR Network a
port2 Up PHX-RT01 120 BR Network b
port3 Down - - - - -
port4 Down - - - - -
port5 Up PHX-SW003 120 B - 48
port6 Up PHX-SW002 120 B - 24
port7 Down - - - - -
port8 Up PHX-SW001 120 B - 48
port9 Down - - - - -
port10 Down - - - - -
port11 Down - - - - -
port12 Down - - - - -
port13 Down - - - - -
port14 Down - - - - -

LLDP on FortiSwitch Managed by FortiLink

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