Network
banshee/network-collection/network/snmp/
lldp-neighbors
The LLDP neighbors of a switch or a router by SNMP (LLDP-MIB): who is on each port, and an expected neighbor gone.
by banshee1 installation2 versions
LLDP neighbors of a device, by SNMP
Returns, for each local port of a switch or a router where LLDP sees a neighbor, the name of that neighbor and its port, and the number of neighbors. Two watches are offered: a neighbor gone from a port where one is expected, and no neighbor at all.
How it works
The collector reads the neighbors the device learned by LLDP (LLDP-MIB, IEEE 802.1AB): lldpRemTable, and lldpLocPortTable for the names of the local ports.
- A local port is named by its LLDP id when that id is a name (
Gi1/0/48,ether1), otherwise by its description; failing both, by its number (port 12). A MAC address is never taken for a name. - The neighbor is the name it announces (
lldpRemSysName),unnamedwhen it announces none; its port, the id it announces when it is a name, otherwise its description. - Two neighbors on one port (a phone and the computer behind it) each keep their own: the second carries its index.
- A neighbor that goes away leaves the table: its port is no longer returned. "Neighbor gone" raises for the ports named on the probe where no neighbor is seen any more: name the uplinks, the links between switches, and the ports of the servers.
The collector only reads: SNMP sends nothing but reads.
Prerequisites
- LLDP enabled on the device and on its neighbors.
- The SNMP agent of the device enabled, reachable from the poller (UDP 161), its access restricted to the poller.
- The view granted to the poller includes
lldpMIB(.1.0.8802.1.1.2). - Read-only access, SNMPv2c or SNMPv3, set on the host or one of its folders (
protocol:snmp:*variables). - Versions: any device whose agent serves LLDP-MIB (IEEE 802.1AB-2005), whatever its brand. A device that serves only the later LLDP-V2-MIB is not read.
Outputs
| Name | Label | Unit | Per instance |
|---|---|---|---|
neighbor | Neighbor | — | yes, per port |
neighbor-port | Port of the neighbor | — | yes, per port |
neighbors | Neighbors | — | no |
Watches
| Name | Title | Kind | Defaults | Checked by default |
|---|---|---|---|---|
gone | Neighbor gone | expected instances, on neighbor | no port named: it raises nothing until ports are set on the probe | no |
no-neighbor | No neighbor | below a threshold, on neighbors | critical below 1 | no |
Limits
- A neighbor replaced by another on the same port raises nothing: the port still has a neighbor. Its name is returned, to read.
- A neighbor that announces its chassis and its port by their MAC address only, with no name nor description, shows
unnamedand no port. - The name of a local port depends on what the device puts in its LLDP id: check, on the first run, the names to give "Neighbor gone".