Ansible assert Module: Validate Conditions and Fail Early (Complete Guide)
By Luca Berton · Published 2024-01-01 · Category: troubleshooting
How to use Ansible assert module to validate conditions, check prerequisites, and fail with clear messages. Input validation and pre-flight checks with examples.
Ansible assert Module: Validate Conditions and Fail Early (Complete Guide)
The ansible.builtin.assert module assert that given expressions are true. This guide covers all common use cases with practical playbook examples.
Basic Assertion
Validate Variables
Pre-flight Checks
Quiet Mode
FAQ
What does ansible assert do?
The assert module tests conditions and fails the play with a clear message if any condition is false. Use it for input validation, prerequisite checks, and ensuring hosts meet requirements.
When should I use assert vs when?
Use assert to fail fast with a descriptive error when requirements are not met. Use when to skip tasks conditionally. Assert is for "this must be true", when is for "do this if true".
Conclusion
The ansible.builtin.assert module is a versatile tool for assert that given expressions are true. Use the examples above as starting points and adapt them to your infrastructure needs.
Related Articles • Ansible Playbook Guide • Ansible Variables Guide
Category: troubleshooting