pyATS, the Cisco python automation tool

Automation is a core element in the management of network devices.
In this post, I tried to set up the pyATS toolset by Cisco. It's a library that can be used in full python code and has a CLI tool add-on. It's vendor agnostic, and you can run your tests or operations tasks.

The installation

pyATS needs to be installed on Linux based system, as I'm using a Windows setup, I installed it on WSL.
I installed pyATS with the Python package manager, pip :

pip install "pyats[full]"

Once installed, the libraries are available to import in your Python code along with the CLI tool.

Write the python code

Your devices have to be loaded in a testbed instance.
The said devices are defined in a YAML file.
Once your target device is selected, you can extract and parse the result of a command.
The pyATS ecosystem has built-in parser, for commands like show inventory, but you can write your own parser for specific use-case.

from genie.testbed import load

testbed = load('my_testbed.yaml')
dev = testbed.devices['nx-osv-1']
dev.connect()
p1 = dev.parse('show inventory')

print('Slot 1 serial number:' + p1['name']['Slot 1']['serial_number'])

My devices to TestBed

Devices information have to be stored in a yaml file, my_testbed.yaml in the above example. It contains device information like ip addresses, OS, hostname, login, password, and so on.

devices:
  R1:
    connections:
      cli:
        ip: 10.10.10.11
        protocol: ssh
    credentials:
      default:
        password: password
        username: admin
      enable:
        password: password
    os: iosxe
    platform: asr1k
    type: iosxe

To avoid any typo, a csv(or xls) file can be used to store the devices data.

Once all values completed, you can then convert the csv file to YAML format using the pyats cli:

(pyATS) ➜  pyats create testbed file --path ./my_devices.csv --output ./my_testbed.yaml