Book Image

Mastering Python Networking

Book Image

Mastering Python Networking

Overview of this book

This book begins with a review of the TCP/ IP protocol suite and a refresher of the core elements of the Python language. Next, you will start using Python and supported libraries to automate network tasks from the current major network vendors. We will look at automating traditional network devices based on the command-line interface, as well as newer devices with API support, with hands-on labs. We will then learn the concepts and practical use cases of the Ansible framework in order to achieve your network goals. We will then move on to using Python for DevOps, starting with using open source tools to test, secure, and analyze your network. Then, we will focus on network monitoring and visualization. We will learn how to retrieve network information using a polling mechanism, ?ow-based monitoring, and visualizing the data programmatically. Next, we will learn how to use the Python framework to build your own customized network web services. In the last module, you will use Python for SDN, where you will use a Python-based controller with OpenFlow in a hands-on lab to learn its concepts and applications. We will compare and contrast OpenFlow, OpenStack, OpenDaylight, and NFV. Finally, you will use everything you’ve learned in the book to construct a migration plan to go from a legacy to a scalable SDN-based network.
Table of Contents (22 chapters)
Title
Humble Bundle
Credits
Foreword
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
12
OpenStack, OpenDaylight, and NFV

Network dynamic operations


Our API can now provide static information about the network; anything that we can store in the database can be returned to the user. It would be great if we can interact with our network directly, such as query the device for information or push configuration changes to the device.

We will start this process by leveraging the script we have already seen in Chapter 2, Low-Level Network Device Interactions for interacting with a device via Pexpect. We will modify the script slightly into a function we can repeatedly use in chapter9_pexpect_1.py:

# We need to install pexpect for our virtual env
$ pip install pexpect

$ cat chapter9_pexpect_1.py
import pexpect

def show_version(device, prompt, ip, username, password):
    device_prompt = prompt
    child = pexpect.spawn('telnet ' + ip)
    child.expect('Username:')
    child.sendline(username)
    child.expect('Password:')
    child.sendline(password)
    child.expect(device_prompt)
    child.sendline('show version...