Ansible Configuration and Setting

Ansible Configuration and Setting

Ansible supports several sources for configuring its behavior, including an ini file named ansible.cfg, environment variables, command-line options, playbook keywords, and variables. This flexibility allows users to customize and optimize Ansible for their specific environments and needs. For a detailed guide on Ansible configuration.

The Configuration File

Changes to Ansible’s behavior can be made in a configuration file. Ansible will search for this configuration file in the following order:

1. ANSIBLE_CONFIG (environment variable if set)
2. ansible.cfg (in the current directory)
3. ~/.ansible.cfg (in the home directory)
4. /etc/ansible/ansible.cfg

Ansible will process the list and use the first configuration file it finds, ignoring all others. This hierarchical search allows for different configurations based on the context in which Ansible is being used.

The ansible-config Utility

The ansible-config utility is a powerful tool for viewing, listing, or dumping the various settings available for Ansible. This utility helps users manage and understand their Ansible configurations effectively.

Viewing the Current Configuration

You can use the ansible-config view command to print the content of your current ansible.cfg file. For example:

zolo@u22s:~/ansible-networking-lab$ ansible-config view
[defaults]
inventory=./inventory.cfg
gathering=explicit
host_key_checking=false
deprecation_warnings=false
interpreter_python=auto
retry_files_enabled=false

This output reflects the exact settings in the ansible.cfg file for the current directory.

Dumping the Current Configuration

To dump all of Ansible’s current configuration settings, use the following command:

ansible-config dump

This command provides a comprehensive view of all configuration settings, making it easier to troubleshoot and understand Ansible’s behavior in your environment.

Listing All Parameters

To see a list of all different parameters, their default values, and the possible values you can set, use the ansible-config list command:

ansible-config list

This command is particularly useful for discovering configurable options and understanding the defaults that Ansible uses.

How Ansible Works - Precedence Rules

To give you maximum flexibility in managing your environments, Ansible offers many ways to control how Ansible behaves: how it connects to managed nodes and how it works once it has connected. If you use Ansible to manage a large number of servers, network devices, and cloud resources, you may define Ansible behavior in several different places and pass that information to Ansible in several different ways.

Ansible offers four sources for controlling its behavior. In order of precedence from lowest (most easily overridden) to highest (overrides all others), the categories are:

1. Configuration settings: The settings in your ansible.cfg file.
2. Command-line options: Flags and parameters passed directly in the command line when running Ansible commands.
3. Playbook keywords: Directives specified within your playbooks that control how tasks are executed.
4. Variables: Values defined in your inventory files, playbooks, or directly in tasks, often providing the most granular level of control.

Each category overrides any information from all lower-precedence categories. For example, a playbook keyword will override any configuration setting. Within each precedence category, specific rules apply. However, generally speaking, ‘last defined’ wins and overrides any previous definitions.

Example Configuration

Below is an example configuration file (ansible.cfg) that might be used in a typical lab setup:

[defaults]
inventory=./inventory.cfg
gathering=explicit
host_key_checking=false
deprecation_warnings=false
interpreter_python=auto
retry_files_enabled=false

• inventory: Specifies the path to the inventory file.
• gathering: Controls the gathering of facts; explicit means facts are only gathered when explicitly requested.
• host_key_checking: Disables SSH key checking to avoid issues with new hosts.
• deprecation_warnings: Disables deprecation warnings to reduce clutter in output.
• interpreter_python: Automatically determines the Python interpreter to use.
• retry_files_enabled: Disables the creation of retry files for failed playbook runs.

This configuration helps streamline Ansible’s operation in a controlled lab environment, ensuring that tasks run smoothly without unnecessary interruptions or checks.

By understanding and utilizing the configuration options available in Ansible, you can tailor the tool to better fit your needs, improving efficiency and control over your automation tasks. The ansible-config utility further enhances this capability by providing clear insights into the current settings and available options.