Diagnostics — neighbours#

The Neighbours tab has two panels. LLDP lists what the switches and routers connected to the router announce about themselves: what each interface is plugged into. IPv4 neighbours lists the addresses the router has resolved to MAC addresses on its networks.

LLDP#

When LLDP is off#

The panel reads "LLDP is off. With it on, switches and routers next to the router announce their name and port, and the router announces its own." Press Turn on LLDP to open the LLDP side panel, with LLDP on and Every interface ticked.

The LLDP side panel#

Control	What it sets
LLDP	On or off: "Announce the router to its neighbours, and list theirs." Switching it off and saving removes all the LLDP settings.
Interfaces	Every interface, or clear it and tick the interfaces LLDP runs on, from the router's list. At least one is needed: "Choose where LLDP runs."
Management addresses	The addresses the router announces. Leave empty to let it choose.
Other vendors’ protocols	Cisco (CDP), Extreme (EDP), Foundry (FDP) and Nortel (SONMP), for neighbours that use one of these instead of LLDP.

Press Save changes to add the settings to the pending changes, then Apply changes in the bar at the bottom of the page. The pending change reads Turn on LLDP, Change LLDP settings or Turn off LLDP. Advanced mode also shows the commands the change makes. Editing needs the operator role and a licence.

When LLDP is on#

The panel title shows how many neighbours have announced themselves, and Edit opens the same side panel. Each neighbour is a row:

Column	What it shows
Device	The name the neighbour announces.
Interface	The router's interface the announcement arrived on.
Protocol	The protocol it was announced with.
Capabilities	What the neighbour says it is, as capability letters such as B (bridge) or R (router).
Platform	The neighbour's model or software, as it announces it.
Their port	The neighbour's port at the other end of the cable.

A column the router reports under another name is shown under that name.

Until a neighbour has announced itself, the panel reads "No neighbours have announced themselves yet. Neighbours announce every 30 seconds, and only those with LLDP on are listed." If the router could not read its list of neighbours, the reason follows. The panel refreshes every 15 seconds.

A neighbour is listed only if it announces itself: LLDP, or one of the other vendors' protocols ticked in the side panel, must be on at the other end too.

IPv4 neighbours#

The router's neighbour table: every IPv4 address it has resolved to a MAC address. The panel title shows how many there are, and the filter matches any column. It refreshes every 10 seconds.

Column	What it shows
Address	The IPv4 address.
MAC address	The MAC address that answered for it.
Interface	The router's interface it was resolved on.
State	The state of the entry, such as reachable, stale or failed. Reachable is green.

Entries on the router's internal interfaces, such as the network its apps use, are left out.

With no entries, the panel reads No IPv4 neighbours: "IPv6 neighbours are on the IPv6 page." If the table could not be read, the panel says so and offers Retry.

Reading the two together#

Question	Where to look
Is a device on this network at all?	IPv4 neighbours. No entry means the router has not resolved its address: the device is absent, or on another network or VLAN.
Which switch port is this interface plugged into?	LLDP: Their port, on the row with that Interface.
Has a device moved to another interface?	IPv4 neighbours, filtered by its MAC address.
An interface is up but nothing answers.	LLDP: a neighbour listed on that interface means the cable and the switch port work.

What this tab does not do#

No editing of the neighbour table. An entry cannot be added by hand or cleared.
No IPv6 neighbours. They are on the IPv6 page.
No manufacturer names. A MAC address is shown as the router reports it.

For automation#

GET /api/lldp returns the LLDP settings and the neighbours; GET /api/neighbors returns the IPv4 neighbour table. Any role can read both. LLDP changes go through the pending changes, like any other.