Book Image

Python Network Programming Techniques

By : Marcel Neidinger
Book Image

Python Network Programming Techniques

By: Marcel Neidinger

Overview of this book

Network automation offers a powerful new way of changing your infrastructure network. Gone are the days of manually logging on to different devices to type the same configuration commands over and over again. With this book, you'll find out how you can automate your network infrastructure using Python. You'll get started on your network automation journey with a hands-on introduction to the network programming basics to complement your infrastructure knowledge. You'll learn how to tackle different aspects of network automation using Python programming and a variety of open source libraries. In the book, you'll learn everything from templating, testing, and deploying your configuration on a device-by-device basis to using high-level REST APIs to manage your cloud-based infrastructure. Finally, you'll see how to automate network security with Cisco’s Firepower APIs. By the end of this Python network programming book, you'll have not only gained a holistic overview of the different methods to automate the configuration and maintenance of network devices, but also learned how to automate simple to complex networking tasks and overcome common network programming challenges.
Table of Contents (14 chapters)

Retrieving access policies

Access policies configured in your FMC instance can easily be retrieved using the FMC REST API. However, doing GET requests to list large amounts of data can be computationally expensive for the API server. Imagine you have an API that returns you a list of all the policies in your network. This list might have, as an example, 5,000 entries, and retrieving all the information is computationally expensive. Let's imagine the API would always return a full list of entries. If your script now searches for one specific policy, based on the name, and that entry was the first entry in your list, you would have requested the information about the other 4,999 access policies without using the information. To lessen the load on API servers, most REST APIs employ a concept called pagination when dealing with large lists of items.

Instead of always returning all entries, they return you a selection—let's say 50 entries. This response is called a page...