Master Ansible's Built-In Debugger

Table of Contents

1. Introduction to Ansible Debugger
2. Features of Ansible Debugger
3. Installation and Setup
4. Initiating the Ansible Debugger
5. Debugging at Play Level
6. Debugging at Task Level
7. Printing Variables and Arguments
8. Changing Variables and Arguments
9. Stepping Through Execution
10. Conclusion

Introduction to Ansible Debugger

The Ansible Debugger is a powerful built-in tool that allows users to debug their tasks and playbooks in Ansible. Similar to Python's pdb, it helps users step through their code and print out variables at each point to aid in the debugging process. In this article, we will explore the main features and options of the Ansible Debugger, as well as how to use it effectively to troubleshoot and fix issues in Ansible tasks and playbooks.

Features of Ansible Debugger

1. Print out variables and arguments
2. Change variables and arguments
3. Step through execution

Installation and Setup

The Ansible Debugger is installed by default with Ansible, so there is no additional installation required. To initiate the debugger, it can be set at the play level or the task level. It can also be set via environment variables or the config file. The point at which the debugger is triggered can be defined Based on various conditions such as failure, Skipped tasks, or always triggering.

Initiating the Ansible Debugger

To initiate the Ansible Debugger, it can be triggered at the desired point within a task or playbook. This can be done by setting the debugger specific parameters in the task or playbook configuration. The debugger can be set to trigger on different conditions such as failure, skipped tasks, or always triggering.

Debugging at Play Level

Debugging at the play level allows users to step through the execution of a whole play. This can be useful in scenarios where multiple tasks are involved, and users need to examine variables and arguments at different stages of the execution. Users can print out variables and arguments, change them if necessary, and step through the execution to identify and fix issues.

Debugging at Task Level

Debugging at the task level allows users to focus on debugging a specific task within a play. This is helpful when there are multiple tasks involved, but users only want to debug a particular task. Users can print out task-specific variables and arguments, change them if needed, and step through the execution to identify and resolve any issues.

Printing Variables and Arguments

One of the main features of the Ansible Debugger is the ability to print out variables and arguments. This helps users better understand the data being processed at each step and identify any discrepancies or unexpected values. Variables and arguments can be printed using the "task" command in the debugger, which displays them in a formatted manner. The "task.args" command can be used to print task arguments, and specific keys can be selected to display different values.

Changing Variables and Arguments

The Ansible Debugger allows users to change variables and arguments on the fly. This can be useful in scenarios where users want to update a specific variable or argument to test different scenarios. The "task.do_task.args" command can be used to specify the variable or argument to be updated, followed by the new value. This flexibility allows users to modify inputs and observe the impact on the task execution.

Stepping Through Execution

An important aspect of the Ansible Debugger is the ability to step through the execution of code. Users can choose to Rerun a task using the "redo" or "r" command or Continue to the next task using the "continue" or "C" command. This provides users with granular control over the execution flow, allowing them to closely examine the behavior of their code at each step. By stepping through the execution, users can identify issues and ensure the proper functioning of their tasks and playbooks.

Conclusion

The Ansible Debugger is a valuable tool for debugging tasks and playbooks in Ansible. Its features such as printing variables, changing variables, and stepping through execution provide users with powerful capabilities to identify and fix issues. By using the Ansible Debugger effectively, users can improve their troubleshooting capabilities and ensure the smooth execution of their Ansible automation workflows.

Pros:

• Built-in tool, no additional installation required
• Allows step-by-step debugging of tasks and playbooks
• Provides the ability to print variables and arguments
• Allows users to change variables and arguments on the fly
• Granular control over code execution

Cons:

• Not as feature-rich as Python's pdb debugger
• Limited documentation on advanced usage

FAQ

Q: Can the Ansible Debugger be used with tasks from different playbooks? A: Yes, the Ansible Debugger can be used with any task within an Ansible playbook, regardless of its origin.

Q: Can the Ansible Debugger be triggered manually during playbook execution? A: Yes, the Ansible Debugger can also be manually triggered during playbook execution by setting it to always trigger.

Q: Are there any limitations on the size or complexity of data structures that can be printed using the Ansible Debugger? A: No, the Ansible Debugger can handle all sizes and complexities of data structures, allowing users to print and inspect variables of any type.

Q: Can variables and arguments be changed permanently using the Ansible Debugger? A: No, the changes made to variables and arguments using the Ansible Debugger are temporary and applicable only for the current debugging session.

Q: Is the Ansible Debugger compatible with all versions of Ansible? A: Yes, the Ansible Debugger is built-in to Ansible and is compatible with all versions of Ansible.