This section contains information related to the Link Layer Discovery Protocol (LLDP) features on the Cisco Nexus 3550-F Fusion (formerly ExaLINK Fusion). Nexus 3550-Fs purchased as layer 1 only devices (i.e. those which do not have an FPGA module installed) are not capable of receiving or transmitting LLDP information, nor are Nexus 3550-Fs running fastmux firmware.

Displaying LLDP neighbors

LLDP messages will always be received on LLDP capable ports, and the show lldp neighbors command can be invoked at any time to see what entries are in the Nexus 3550-F's database, for example:

admin@@EXALINK-FUSION> show lldp neighbors
Local Port Chassis ID        Port ID           System Name
---------- ----------------- ----------------- --------------------
B1         F4:6D:04:8D:F6:41 64:3F:5F:01:14:A0 MyNetworkDevice
B2         F4:6D:04:8D:F6:41 64:3F:5F:01:14:A1 MyNetworkDevice
B3         F4:6D:04:8D:F6:41 64:3F:5F:01:14:A2 MyNetworkDevice
B4         F4:6D:04:8D:F6:41 64:3F:5F:01:14:A3 MyNetworkDevice

Additional information can be shown by issuing the same command from within the port modal state, for example:

admin@N3550-F> port B1
admin@N3550-F(port:B1)> show lldp neighbors
Port                  : B1

Chassis ID type       : MAC address
Chassis ID            : F4:6D:04:8D:F6:41
Port ID type          : MAC address
Port ID               : 64:3F:5F:01:14:A0
System name           : MyNetworkDevice
System description    : An LLDP enabled device on my network

Management address    :
Interface number type : Unknown

Configuring LLDP

The broadcast of LLDP frames which would allow remote parties to detect the identity of the Nexus 3550-F is configurable on a port-by-port basis, allowing for less congestion on ports that do not require LLDP. Enabling of LLDP transmit must be invoked through the config mode for a specific port:

admin@N3550-F> config port B1
admin@N3550-F(config-port:B1)> lldp transmit
Port B1 LLDP transmit enabled

As long as the specified port forms part of a mux or switch object, it will transmit LLDP frames periodically out that port. Note that this configuration can be done when a port is not a part of an object, however transmission of LLDP frames will not begin until the port is part of a mux or switch object.

Note also that if a mux object is in raw mode, ie where the traffic path from the upstream port to the downstream ports is broadcast via layer 1 only, it's not possible for LLDP transmits to go out a downstream port.

Transmission of LLDP frames can be disabled with the no lldp transmit command:

admin@N3550-F> config port B1
admin@N3550-F(config-port:B1)> no lldp transmit
Port B1 LLDP transmit disabled

This page was last updated on Feb-19-2021.