• Link Layer Discovery Protocol (LLDP)
  • Simulate a LLDP package
  • Enable LLDP
• Query LLDP status

Link Layer Discovery Protocol (LLDP)

LLDP support is introduced by nmstate-0.3.2 using NetworkManager backend.

Once LLDP is enabled, the NetworkManager will listen on LLDP packages, there is no need to run other LLDP agent daemon like lldpad.

Simulate a LLDP package

We stored a captured LLDP package from real LLDP enabled switch and use tcpreply to sent to veth interface.

sudo ip link add eth1 type veth peer name eth1peer
sudo ip link set eth1 up
sudo ip link set eth1peer up
sudo nmcli device set eth1 managed yes
cat | sudo nmstatectl apply - << EOL
interfaces:
  - name: eth1
    type: ethernet
    lldp:
      enabled: true
EOL

URL_BASE="https://github.com/nmstate/nmstate"

wget ${URL_BASE}/raw/base/tests/integration/test_captures/lldp.pcap \
    -O /tmp/lldp.pcap
sudo tcpreplay --intf1=eth1peer /tmp/lldp.pcap

Enable LLDP

cat | sudo nmstatectl apply - << EOL
interfaces:
  - name: eth1
    type: ethernet
    lldp:
      enabled: true
EOL

or

import libnmstate
from libnmstate.schmea import Interface
from libnmstate.schmea import InterfaceType
from libnmstate.schmea import LLDP

libnmstate.apply(
    {
        Interface.KEY: [
            {
                Interface.NAME: "eth1",
                Interface.TYPE: InterfaceType.ETHERNET,
                LLDP.CONFIG_SUBTREE: {LLDP.ENABLED: True},
            }
        ]
    }
)

Query LLDP status

Once NetworkManager received LLDP packages, the libnmstate.show() or nmstatectl.show can query the LLDP information. Example:

interfaces:
- name: eth1
  type: ethernet
  state: up
  ipv4:
    enabled: false
    dhcp: false
  ipv6:
    enabled: false
    autoconf: false
    dhcp: false
  lldp:
    enabled: true
    neighbors:
    - - type: 5
        system-name: Summit300-48
      - type: 6
        system-description: Summit300-48 - Version 7.4e.1 (Build 5)
          05/27/05 04:53:11
      - type: 7
        system-capabilities:
        - MAC Bridge component
        - Router
      - type: 1
        _description: MAC address
        chassis-id: 00:01:30:F9:AD:A0
        chassis-id-type: 4
      - type: 2
        _description: Interface name
        port-id: 1/1
        port-id-type: 5
      - type: 127
        ieee-802-1-vlans:
        - name: v2-0488-03-0505
          vid: 488
        oui: 00:80:c2
        subtype: 3
      - type: 127
        ieee-802-3-mac-phy-conf:
          autoneg: true
          operational-mau-type: 16
          pmd-autoneg-cap: 27648
        oui: 00:12:0f
        subtype: 1
      - type: 127
        ieee-802-1-ppvids:
        - 0
        oui: 00:80:c2
        subtype: 2
      - type: 8
        management-addresses:
        - address: 00:01:30:F9:AD:A0
          address-subtype: MAC
          interface-number: 1001
          interface-number-subtype: 2
      - type: 127
        ieee-802-3-max-frame-size: 1522
        oui: 00:12:0f
        subtype: 4
  mac-address: 82:75:BE:6F:8C:7A
  mtu: 1500