Book Image

Practical Ansible - Second Edition

By : James Freeman, Fabio Alessandro Locati, Daniel Oh
Book Image

Practical Ansible - Second Edition

By: James Freeman, Fabio Alessandro Locati, Daniel Oh

Overview of this book

Ansible empowers you to automate a myriad of tasks, including software provisioning, configuration management, infrastructure deployment, and application rollouts. It can be used as a deployment tool as well as an orchestration tool. While Ansible provides simple yet powerful features to automate multi-layer environments using agentless communication, it can also solve other critical IT challenges, such as ensuring continuous integration and continuous deployment (CI/CD) with zero downtime. In this book, you'll work with the latest release of Ansible and learn how to solve complex issues quickly with the help of task-oriented scenarios. You'll start by installing and configuring Ansible on Linux and macOS to automate monotonous and repetitive IT tasks and learn concepts such as playbooks, inventories, and roles. As you progress, you'll gain insight into the YAML syntax and learn how to port between Ansible versions. Additionally, you'll understand how Ansible enables you to orchestrate multi-layer environments such as networks, containers, and the cloud. By the end of this Ansible book, you'll be well versed in writing playbooks and other related Ansible code to overcome all your IT challenges, from infrastructure-as-a-code provisioning to application deployments and handling mundane day-to-day maintenance tasks.
Table of Contents (21 chapters)
Free Chapter
1
Part 1:Learning the Fundamentals of Ansible
6
Part 2:Expanding the Capabilities of Ansible
12
Part 3:Using Ansible in an Enterprise

Custom conditional statements for networking devices

Although there are no networking-specific Ansible conditionals, conditionals frequently come into play in networking-related Ansible usage.

In networking, it’s common to enable and disable ports. To have data be able to pass through the cable, both ports at the ends of the cable should be enabled, resulting in a connected state (some vendors will use different names for this, but the idea is the same).

Let’s suppose we have two Arista Networks EOS devices, and we issued the ON status on the ports and need to wait for the connection to be up before proceeding.

To wait for the Ethernet4 interface to be enabled, we will need to add the following task to our playbook:

- name: Wait for interface to be enabled
  arista.eos.eos_command:
    commands:
    - show interface Ethernet4 | json
    wait_for:
    - "result[0...