See what the switch says it is#
You will end up with a table of what each neighbouring switch or router announces about itself: its name, the port the cable is in, and what kind of device it is. It shows which switch port each of the router's interfaces is connected to.
Before you start#
- The operator role and a licence.
- LLDP on the switch as well. A neighbour is listed only if it announces itself.
Step 1 — Turn it on#
- Open Observe → Diagnostics and choose the Neighbours tab.
- In the LLDP panel, press Turn on LLDP. The LLDP side panel opens with LLDP on and Every interface ticked.
- To run LLDP on some interfaces only, clear Every interface and tick those interfaces.
- If you need to, add Management addresses, the addresses the router announces; left empty, the router chooses. Under Other vendors’ protocols, tick Cisco (CDP), Extreme (EDP), Foundry (FDP) or Nortel (SONMP) for neighbours that use one of those instead of LLDP.
- Press Save changes, then Apply changes in the bar at the bottom of the page.
The pending change reads Turn on LLDP, with the interfaces and options under it. Advanced mode also shows the commands it makes.
Step 2 — Wait thirty seconds#
Neighbours announce every 30 seconds, and the panel refreshes every 15 seconds. 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.
Check it worked#
The LLDP panel lists one row per neighbour, and its title shows how many there are.
| Column | What it shows |
|---|---|
| Device | The neighbour's name. |
| 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. |
| Their port | The neighbour's port at the other end of the cable. |
What it settles#
| Question | The answer is in |
|---|---|
| Which switch port is this interface plugged into? | Their port, on the row with that Interface. |
| Are both ports of this bond on the same switch? | Two rows with the same Device. See Bond two ports. |
| Is there a device on this network I did not expect? | A row you do not recognise. |
The IPv4 neighbours panel on the same tab is the other half: LLDP names the devices, the neighbour table lists the addresses.
Changing or undoing it#
Press Edit in the LLDP panel to change the interfaces or options. To turn LLDP off, switch LLDP off in the side panel and press Save changes; all its settings are removed. Then press Apply changes.