Network Automation

Getting Started Roadmap

Building your own automation workflow with open source tools doesn't have to be overly complicated. Start by familiarizing yourself with these foundational elements:

• Linux
• Python
• Git

Next... setup your machine with the suggested tools below.

Install these as part of your Automation Toolbox

• Microsoft VSCode Editor
• Git
• Ansible
• Python 3
• Docker Desktop

Once these tools are installed, take a look at the examples below and try them out!

First let's clone the repository from GitHub

git clone https://github.com/mthiel117/webinar_feb9.git

Example #1 - Python Script to gather Network Inventory from Arista Network switches

Quick example of using the Arista eAPI to gather information (hostname, uptime, mac-address, lldp neighbors, etc...) from a network of switches.

Requirements: Git, Python2 or Python3 (preferred) installed and Arista switches that are reachable from your workstation. You will need to modify the IP address list of switches in the script to match your environment.

Install the JSONRPCLIB module to allow eAPI connection to be built to the switch.

If you are running python2, install jsonrpclib module

pip install jsonrpclib

If you are running python3, install jsonrpclib-pelix module

pip3 install jsonrpclib-pelix

In this example, we have a running lab of 5 Arista switches available to query.

cd python-example
./net-info.py

Output should look similar to the following:

Example #2 - Ansible Playbook to Create Base Configs from a CSV File

The following playbook creates a unique base device configuration for each row in the CSV file.

File/Directory	Description
./playbooks/create_base_configs.yml	Playbook
./templates/base-cfg.j2	Jinja Template
./datafiles/devices.csv	CSV File of Device with header row (used for variable names in Jinja)
./base-configs/	Directory for rendered configuration files

Test it out: (requires ansible to be installed)

cd csv-playbook-example
ansible-playbook create_base_configs.yml

Output should look similar to the following:

Look for config files inside the ./base-configs/ directory.

Docker Image & Container Build

Prerequisites

• Docker installed on local machine
• https://docs.docker.com/get-docker/

STEP 1 - Change to 'docker' Directory

cd docker

STEP 2 - Build Docker Image

docker build -f Dockerfile --tag mydevbox/base .

STEP 3 - Run container and attach to local current directory

Launches Docker container mydevbox/base and attaches to your local current directory

MacOS

docker run -it --rm -v $(PWD):/workspace mydevbox/base

Windows

docker run -it --rm -v %cd%:/workspace mydevbox/base

STEP 4 - Change into Directory 'workspace'

While in the container, change to directory 'workspace'. The contents will be a pointer to your local directory the container was launched from.

cd workspace
ls -l

You know are running a full Ubuntu container with:

• Ubuntu 20.04.1
• Python 3.8.5
• Ansible 2.10.5
• Modules for Netbox & YAML with dependencies pre-installed

pip list

Package      Version
------------ ---------
ansible      2.10.4
ansible-base 2.10.5
certifi      2020.12.5
cffi         1.14.4
chardet      4.0.0
cryptography 3.4.3
dbus-python  1.2.16
idna         2.10
Jinja2       2.11.3
MarkupSafe   1.1.1
netaddr      0.8.0
packaging    20.9
pip          20.0.2
pycparser    2.20
PyGObject    3.36.0
pynetbox     5.3.1
pyparsing    2.4.7
PyYAML       5.4.1
requests     2.25.1
setuptools   45.2.0
six          1.15.0
urllib3      1.26.3
wheel        0.34.2

For integrating your container with VSCode check out:

Docker & VSCode Integration