Nornir

Installation

• pip install nornir

Plugin Installation

• pip install nornir_netbox

• pip install nornir_napalm

• pip install nornir_netmiko

Configuration

• Inventory includes 3 files: hosts.yaml, groups.yaml and defaults.yaml

hosts.yml

---
host1.cmh:
    hostname: 127.0.0.1
    port: 2201
    username: vagrant
    password: vagrant
    platform: linux
    groups:
        - cmh
    data:
        site: cmh
        role: host
        type: host
        nested_data:
            a_dict:
                a: 1
                b: 2
            a_list: [1, 2]
            a_string: "asdasd"

host2.cmh:
    hostname: 127.0.0.1
    port: 2202
    username: vagrant
    password: vagrant
    platform: linux
    groups:
        - cmh
    data:
        site: cmh
        role: host
        type: host
        nested_data:
            a_dict:
                b: 2
                c: 3
            a_list: [1, 2]
            a_string: "qwe"

groups.yaml

---
global:
    data:
        domain: global.local
        asn: 1

eu:
    data:
        asn: 65100

bma:
    groups:
        - eu
        - global

cmh:
    data:
        asn: 65000
        vlans:
          100: frontend
          200: backend

defaults.yaml

---
data:
    domain: acme.local

Filtering

• Using filter function for basic filtering

• Using F function for advance filtering

Using Filter Function

# Print list of host
import json
inv = nr.inventory.dict()
dev = nr.inventory.hosts['br1sw'].dict()
print(json.dumps(dev, indent=2))

# Run Task with filtered devices
import os, json
from nornir import InitNornir
from nornir_napalm.plugins.tasks import napalm_cli
from nornir_utils.plugins.functions import print_result
nr = InitNornir(config_file="config.yaml")
nr.inventory.defaults.username = os.getenv("nruser")
nr.inventory.defaults.password = os.getenv("nrpass")

dev = nr.filter(name='br1sw')
result = dev.run(napalm_cli, commands=["show ip int brief", "show ver"])

# Use Nornir-supplied function to pretty-print the result
# to see a recap of all actions taken.
print_result(result)

Using plugins

Netbox

config.yaml

---
inventory:
  plugin: NetBoxInventory2
  options:
    nb_url: 'http://127.0.0.1:8000'
    ssl_verify: False
    nb_token: '98f02164d0ef62be'
    # use platform slug as platform
    use_platform_slug: true

runbook.py

import os, json
from nornir import InitNornir
nr = InitNornir(config_file="config.yaml")
nr.inventory.defaults.username = os.getenv("nruser")
nr.inventory.defaults.password = os.getenv("nrpass")
inv = nr.inventory.dict()
dev = nr.inventory.hosts['br1sw'].dict()
print(json.dumps(dev, indent=2))

Napalm

Reference

• https://theworldsgonemad.net/2021/nornir-basics/

• https://theworldsgonemad.net/2021/nornir-inventory/

• https://theworldsgonemad.net/2021/nornir-tasks/

• https://ultraconfig.com.au/blog/nornir-framework-full-tutorial-for-beginners/

• https://blogs.cisco.com/developer/nornir-python-automation-framework

• https://nornir.readthedocs.io/en/latest/tutorial/index.html

• https://nornir.tech/nornir/plugins/

• https://blogs.cisco.com/developer/nornir-python-automation-framework

• https://ultraconfig.com.au/blog/nornir-framework-full-tutorial-for-beginners/

• https://theworldsgonemad.net/2021/nornir-basics/#task-options

• https://pynet.twb-tech.com/blog/nornir-an-introduction.html

• https://pynet.twb-tech.com/blog/nornir-using-ansible-inventory-part-1.html

• https://www.packetcoders.io/how-to-build-a-network-automation-stack-with-nornir-napalm-and-netbox/

• https://snyk.io/advisor/python/nornir/example

• https://github.com/ThreeFDDI/nornir-netbox-demo/blob/master/nornir-netbox-demo.py

• https://www.linkedin.com/pulse/peek-network-automation-using-python-nornir-jinja2-isolate-dadanema/

• Nornir Filter: https://rayka-co.com/lesson/nornir-filter-inventory/

• https://nornir.readthedocs.io/en/latest/howto/filtering_deep_dive.html

• TextFSM parser: https://rayka-co.com/lesson/textfsm-parser-in-nornir-automation-scripts/

• https://github.com/asadpoor/devnet/tree/master/pyhton_nornir

• Nornir Script: Find Interfaces with CRC Errors: https://developer.cisco.com/codeexchange/github/repo/bsingh23/nornir_crc_errors/