Put the concepts you learned to work with this quick tutorial. Install Ansible, execute a network configuration command manually, execute the same command with Ansible, then create a playbook so you can execute the command any time on multiple network devices.
To confirm your credentials, connect to a network device manually and retrieve its configuration. Replace the sample user and device name with your real credentials. For example, for a VyOS router:
..code-block:: bash
ssh my_vyos_user@vyos.example.net
show config
exit
This manual connection also establishes the authenticity of the network device, adding its RSA key fingerprint to your list of known hosts. (If you have connected to the device before, you have already established its authenticity.)
Instead of manually connecting and running a command on the network device, you can retrieve its configuration with a single, stripped-down Ansible command:
If you want to run this command every day, you can save it in a playbook and run it with ``ansible-playbook`` instead of ``ansible``. The playbook can store a lot of the parameters you provided with flags at the command line, leaving less to type at the command line. You need two files for this - a playbook and an inventory file.
The playbook sets three of the seven values from the command line above: the group (``hosts: all``), the connection method (``connection: ansible.netcommon.network_cli``) and the module (in each task). With those values set in the playbook, you can omit them on the command line. The playbook also adds a second task to show the config output. When a module runs in a playbook, the output is held in memory for use by future tasks instead of written to the console. The debug task here lets you see the results in your shell.
3. Now that you can retrieve the device config, try updating it with Ansible. Download :download:`first_playbook_ext.yml <sample_files/first_playbook_ext.yml>`, which is an extended version of the first playbook:
The extended first playbook has four tasks in a single play. Run it with the same command you used above. The output shows you the change Ansible made to the config:
The ``gather_facts`` keyword now supports gathering network device facts in standardized key/value pairs. You can feed these network facts into further tasks to manage the network device.
You can also use the new ``gather_network_resources`` parameter with the network ``*_facts`` modules (such as :ref:`arista.eos.eos_facts <ansible_collections.arista.eos.eos_facts_module>`) to return just a subset of the device configuration, as shown below.
You can store these facts and use them directly in another task, such as with the :ref:`eos_interfaces <ansible_collections.arista.eos.eos_interfaces_module>` resource module.
