Introduction
In the realm of IT automation, Ansible is a powerful tool that helps streamline tasks and manage infrastructure efficiently. While Ansible makes automation accessible and user-friendly, it’s essential to follow best practices to ensure the reliability and predictability of your automation workflows. One critical aspect of writing Ansible playbooks is error handling, and that’s where the ignore_errors [Ansible-Lint](/articles/ansible-lint) rule comes into play. This rule checks that playbooks do not use the ignore_errors directive to ignore all errors. In this article, we’ll explore the rationale behind this rule and best practices for handling errors in Ansible playbooks.
The Role of ignore_errors in Ansible
In Ansible playbooks, the ignore_errors directive is employed to instruct Ansible to continue execution even when a task fails. This directive can be beneficial in specific scenarios, but it should be used judiciously. Using ignore_errors to bypass all errors across all tasks in a playbook is generally discouraged. Here’s why relying too heavily on ignore_errors is problematic:
1. Concealing Failures: When you ignore all errors across tasks, you essentially hide any failures that occur during playbook execution. This can lead to the execution of tasks that shouldn’t run, potentially causing further problems down the line.
2. Incorrect Task Status: The use of ignore_errors can wrongly mark tasks as “succeeded” even when they encounter errors. This can be misleading and prevent operators from identifying the actual source of issues.
3. Unintended Side Effects: Tasks that fail can have consequences. Ignoring these errors means that you may unknowingly leave the system in an inconsistent state, leading to unexpected issues and behavior.
Best Practices for Handling Errors
To ensure that your Ansible playbooks handle errors effectively, consider the following best practices:
1. Use ignore_errors Selectively
Instead of applying ignore_errors globally to all tasks, use it selectively. This means using ignore_errors only when it makes sense and the failure of a particular task doesn’t disrupt the overall playbook execution. You should have a clear and documented reason for using ignore_errors on a specific task.
2. Utilize register for Error Handling
When a task could potentially generate errors, consider using the register module to capture the task’s output, including error messages and other relevant information. By registering the task’s output, you can later evaluate it, decide on appropriate actions, and handle errors in a controlled and predictable manner.
3. Define Error Conditions
For tasks where errors may occur, define precise error conditions using the failed_when directive. Specify under what circumstances the task should be considered as having failed. This allows you to have fine-grained control over error handling while preventing unintended side effe