Python for Network Automation

Learn Network Programmability with Python, GNS3, and Cisco devices.

1. What you’ll learn

   • Python fundamentals

   • Network Automation with Python

2. About the author

   • Associate Engineer (DAE in Electronics) exploring network automation, my skills as an Associate Engineer include:

     • Routing and Switching

     • OFC/LAN Networking

     • IP Addressing and Sub-netting

     • Computer Basics - Windows 7/10

     • Linux and Ubuntu Desktop/Server

     • VMware/KVM/VirtualBox

     • Docker/Vagrant - Hands On

     • Ansible for Network Automation

     • Python for Network Automation

3. Conventions

This book is a guide for network engineers and is intended for network engineers to write code. Therefore, no time is spent on coding style. Programming concepts such as object-oriented programming are not covered in detail due to their complexity. However, this book mainly focuses on getting Python scripting to work with minimal effort to automate network devices.

Warning

This book is under development.

Table of Contents:

• What is Network Automation?
  • What is Computer Programming?
  • Understanding Python Language
  • Python for Network Engineers
  • Installing Python
  • Python Characteristics
  • dir() and help()
  • What is Python pip?
  • Installation
  • Installing Modules with pip
  • Python Virtual Environments
• Basic Data Types
  • Variables in Python
  • Python Naming Conventions
  • Understanding Python Strings
  • Understanding Python Numbers
  • Integers in Python
  • Floats in Python
  • Numbers - Other Operators
  • Type Casting in Python
  • Useful Built-in Functions
  • Python Operators
• Collections and Sequences in Python
  • Understanding Lists in Python
  • Understanding Tuples in Python
  • What is a Tuple?
  • Storing Different Data Types in a Tuple
  • Using Parentheses
  • Checking the Type of a Tuple
  • Immutable Nature of Tuples
  • Accessing Elements in a Tuple
  • Restrictions on Tuple Operations
  • Tuple Notation
  • Understanding Sets in Python
  • How to Use Sets in Python
  • Creating Sets
  • Using Sets
  • How to Modify Sets in Python
  • How to Perform Set Operations in Python
  • How Set Operations Can Help Network Engineers
  • Python Dictionaries: A Network Engineer’s Guide
  • Similarities with Lists: Mutability
  • Using Curly Braces to Create a Dictionary
  • Navigating Dictionaries in Python
  • Dictionary Toolbox: Methods
  • Exploring Keys, Values, and Items
  • Dynamic Modifications with .pop()
  • Deletion Strategies: del and update
  • Dictionary Iteration Techniques
  • Nested Dictionaries in Python
  • Understanding Mutable and Immutable Objects in Python
  • Mutable Objects in Python
  • How Lists Work Internally
  • List Comprehensions: Simplifying Data Manipulation
  • Advanced Techniques with Nested List Comprehensions
  • Using List Comprehensions for Data Transformation
  • Pros and Cons of List Comprehensions
  • Set Comprehensions in Python
• Conditional Statements**
  • Understanding Booleans
  • Boolean Logic in Python
  • Truthy and Falsy Values in Python
  • None in Python
  • Conditional Statements in Python
  • Importance of Conditions in Programming
  • Conditional Statements - elif and else
  • Comparison Operators and Conditionals
  • Logical Operators and Conditional Statements
  • Nested Conditional Statements
  • Truthy and Falsy Values in Python
  • Idiomatic Expressions in Python
• Loops in Python
  • Understanding the For Loop in Python
  • Nesting Loops in Python
  • While Loop in Python
  • For vs. While Loops
• File Handling in Python
  • Working with Files in Python
• Exception Handling in Python for Network Engineers
  • Understanding Exceptions
  • Handling Exceptions
  • Handling Specific Exceptions
  • Handling Multiple Exceptions
  • Exceptions as Variables
• Functions and Classes
  • Functions and Classes
  • Built-in Functions
  • User-defined Functions
  • Return Values
  • Function Arguments
  • Positional Arguments
  • Default Arguments
  • Keyword (Named) Arguments
  • *args and **kwargs in Functions
  • Handling Tuple and Dictionary as Arguments
  • Scope of Variables in function
  • Classes and Objects
• Network Automation Lab
  • Setting Up a Network Lab with GNS3
  • Prerequisites of Lab
  • Starting the Lab Environment
  • Adding Cloud Node to GNS3
  • Installing VSCode and SSH Extension
  • Connecting VSCode to Ubuntu Server
  • Finalizing the Lab Setup
  • Conclusion
• Telnet Programming in Python: Streamlining Network Operations
  • Understanding Telnet’s Operation
  • Importance in Network Programming
  • Integration with Python
  • Basics of Telnetlib
  • Security Considerations
• Paramiko - Secure SSH Connections in Python
  • Setting up Paramiko for SSH Communication
  • Establishing Secure Connections to Network Devices
  • Executing Commands and Handling Responses Asynchronously
  • Handling Exceptions and Error Scenarios Gracefully
  • Advanced Example: Creating Loopback Interfaces
  • Connecting to Multiple Devices
  • Connecting to Multiple Devices with a List
  • Conclusion
• Simplifying Network Device Management with Netmiko
  • What is Netmiko?
  • Installing Netmiko
  • Connecting a Single Device
  • Simplify Device Connections with Python Dictionaries in Netmiko
  • Enabling Privilege EXEC Mode with Netmiko
  • Device Configuration with Netmiko
  • Safeguarding Passwords in Network Automation with Python’s getpass
  • Sending Multiple Commands
  • Connecting to Multiple Devices with Netmiko
  • Simplifying Network Configuration with Netmiko
  • Conclusion
• NAPALM - Unified Network Device Management
  • Overview of NAPALM and Its Purpose
  • Installation and Configuration Steps
  • Working with Different Vendor Platforms using NAPALM
  • Integrating NAPALM with Other Automation Tools and Frameworks
  • Configuration support Method
• Getting Started with Nornir - Network Automation
  • Prerequisites and Key Points
  • Overview of Nornir Components
  • Configuring Nornir
  • Writing and Running Your First Nornir Script
  • Integrating Netmiko with Nornir
  • Integrating Python NAPALM with Nornir
• Appendix
  • Simplifying Network Automation with Python dotenv
  • Understanding Python-dotenv
  • Key Benefits of Python-dotenv
  • Getting Started with Python-dotenv
  • Using Python-dotenv in Your Scripts
  • Python Development: Essential VS Code Settings
  • What is VS Code?
  • What is a Virtual Environment?
  • Essential Linux Networking Commands
  • Essential Windows 10 Networking Commands
  • 1. ipconfig
  • 2. netsh
  • 3. route
  • 4. ping
  • 5. tracert
  • 6. netstat
  • 7. nslookup
  • 8. getmac
  • 9. telnet
  • 10. pscp
  • 11. nmap
  • 12. arp
  • 13. net use
  • 14. gpupdate
  • 15. systeminfo
  • 16. tasklist
  • 17. taskkill
  • Using help Command
  • Additional Tips