Ansible Environment Variables
Ansible is an open-source software provisioning, configuration management, and application deployment tool. It uses declarative language to describe the system’s desired state and leverages SSH to communicate and enforce that state on the target machines.
Environment variables are some of the most useful tools in dynamic environments. But what exactly are environment variables?
Environment variables are key-value pairs that can influence the behavior of the tools that run in a system. They act as global settings which allows the different processes to communicate and configure their behavior without modifying the code.
This tutorial teaches us how to work with environment variables in Ansible using various methods and techniques.
Environment Variables in Ansible
Ansible has numerous environment variables that we can modify and configure to match our desired needs. Such environment variables dictate everything from where Ansible looks for its inventory, how it logs the messages, to the number of parallel tasks it should run.
It is good to remember that environment variables may be missing or introduced depending on the installed Ansible version and the installed modules.
Setting the Ansible Environment Variables
We can set the environment variables in multiple ways:
Using the Shell
Before running an Ansible command, we can export the variable in the system shell and then reference it as follows:
This sets a different path for the ANSIBLE_INVENTORY variable which determines where Ansible will look for the inventory list.
Ansible Configuration File
We can also configure the environment variables in Ansible’s configuration file (ansible.cfg) using the env section:
The given entry uses the Ansible [defaults] block.
In line with the Ansible Command
The third method to configure the environment variables in Ansible is passing them directly in Ansible ad hoc commands.
Accessing the Ansible Environment Variables
We can access the environment variables in an Ansible playbook and roles using the lookup plugin. An example is as follows:
We covered the functionality of environment variables in the context of Ansible. Using this tutorial, you learned the various methods and techniques of setting the environment variables and looking them up in Ansible playbooks.