The Link Layer Discovery Protocol page shows how IPFire advertises itself to directly connected switches and other network devices and lists the neighbours it discovers on each interface. LLDP is a vendor-neutral standard (IEEE 802.1AB) that allows devices to publish information such as system name, description, port, VLAN and capabilities to adjacent systems on the same Layer 2 segment. Alternatively, Cisco Discovery Protocol (CDPv2) is supported as well.
This feature is available under Network > Link Layer Discovery Protocol and focuses purely on configuration and monitoring through the web interface.
Global Settings
The Global settings box controls how IPFire participates in LLDP:
- Enabled When checked, enables the service.
- Description Optional text that IPFire advertises as its LLDP system description. This is what connected switches and other neighbours display for the IPFire system. If a description is entered, that text is broadcast via LLDP. Otherwise IPFire sends a default description based on its version and kernel release.
When enabled, IPFire starts the LLDP service and will listen to announcements from other peers. If an announcement is being received, IPFire will start to send its own announcements matching the protocol of the remote device. For example, if IPFire is connected to a switch that supports LLDP, it will respond using LLDP. If the switch sends Cisco Discovery Protocol (CDPv2) announcements, IPFire will respond using CDPv2.
Neighbour information from connected devices is then collected and shown in the table below. Neighbours might take some time to appear because many devices transmit frames at intervals of around 10–30 seconds.
Neighbours Table
When LLDP is enabled and neighbouring devices support LLDP or compatible discovery protocols, the Neighbours section shows a table with one row per detected neighbour. The columns are:
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Name The remote system’s name (chassis name). This is usually the hostname configured on the switch, access point, or other device.
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Interface The IPFire interface on which the neighbour has been discovered (for example,
green0). This indicates which physical or virtual link the neighbour is connected to. -
Port The port identifier on the neighbour side. On a switch this often matches the port label on the device front panel, which helps mapping cables to interfaces.
-
VLAN The VLAN identifier advertised by the neighbour, where this information is provided. This can be used to confirm that the expected VLAN is configured on the link.
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Protocol The discovery protocol used for this entry. IPFire’s LLDP daemon supports LLDP itself and can also interpret several proprietary discovery protocols such as Cisco Discovery Protocol (CDP).
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Description The neighbour’s own system description, for example a hardware model string or a text configured on the switch. This field comes from the remote device and is unrelated to the Description field in the Global Settings box, which controls what IPFire sends to others.