Chapter 40. Introduction to Nmstate

The libnmstate Python library enables developers to use Nmstate in their own application.

To use the library, import it in your source code:

import libnmstate

Note that you must install the nmstate and python3-libnmstate packages to use this library.

import libnmstate
from libnmstate.schema import Interface

net_state = libnmstate.show()
for iface_state in net_state[Interface.KEY]:
    print(iface_state[Interface.NAME] + ": "
          + iface_state[Interface.STATE])

You can use the nmstatectl utility to store the current network configuration of one or all interfaces in a file.

You can then use this file to:

For example, you can export the settings of the enp1s0 interface to a file, modify the configuration, and apply the settings to the host.

The network RHEL system role supports state configurations in playbooks to configure the devices. For this, use the network_state variable followed by the state configurations.

Benefits of using the network_state variable in a playbook:

For example, to create an Ethernet connection with dynamic IP address settings, use the following vars block in your playbook:

vars:
  network_state:
    interfaces:
    - name: enp7s0
      type: ethernet
      state: up
      ipv4:
        enabled: true
        auto-dns: true
        auto-gateway: true
        auto-routes: true
        dhcp: true
      ipv6:
        enabled: true
        auto-dns: true
        auto-gateway: true
        auto-routes: true
        autoconf: true
        dhcp: true

vars:
  network_connections:
    - name: enp7s0
      interface_name: enp7s0
      type: ethernet
      autoconnect: yes
      ip:
        dhcp4: yes
        auto6: yes
      state: up

For example, to only change the connection status of dynamic IP address settings that you created as above, use the following vars block in your playbook:

vars:
  network_state:
    interfaces:
    - name: enp7s0
      type: ethernet
      state: down

vars:
  network_connections:
    - name: enp7s0
      interface_name: enp7s0
      type: ethernet
      autoconnect: yes
      ip:
        dhcp4: yes
        auto6: yes
      state: down