Book Image

Python Network Programming

By : Abhishek Ratan, Eric Chou, Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker
Book Image

Python Network Programming

By: Abhishek Ratan, Eric Chou, Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker

Overview of this book

This Learning Path highlights major aspects of Python network programming such as writing simple networking clients, creating and deploying SDN and NFV systems, and extending your network with Mininet. You’ll also learn how to automate legacy and the latest network devices. As you progress through the chapters, you’ll use Python for DevOps and open source tools to test, secure, and analyze your network. Toward the end, you'll develop client-side applications, such as web API clients, email clients, SSH, and FTP, using socket programming. By the end of this Learning Path, you will have learned how to analyze a network's security vulnerabilities using advanced network packet capture and analysis techniques. This Learning Path includes content from the following Packt products: • Practical Network Automation by Abhishek Ratan • Mastering Python Networking by Eric Chou • Python Network Programming Cookbook, Second Edition by Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker
Table of Contents (30 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
Index

Group and host variables


Note that, in the previous playbook, chapter8_8.yml, we have repeated ourselves in the username and password variables for the two devices under the nexus_devices variable:

    vars:
      nexus_devices: {
        "nx-osv-1": {
          "hostname": "nx-osv-1",
          "username": "cisco",
          "password": "cisco",
          "vlans": [100, 200, 300],
        <skip>
        "nx-osv-2": {
          "hostname": "nx-osv-2",
          "username": "cisco",
          "password": "cisco",
          "vlans": [100, 200, 300],
        <skip>

This is not ideal. If we ever need to update the username and password values, we will need to remember to update at two locations. This increases the management burden as well as the chances of making mistakes. For a best practice, Ansible suggests that we use the group_vars and host_vars directories to separate out the variables.

Note

For more Ansible best practices, check out http://docs.ansible.com/ansible/playbooks_best_practices...