Error Handling¶

Why This Exists¶

By default, a failed task on one host removes that host from the rest of the play but lets other hosts continue — that default is usually right, but not always, and this page covers the keywords that change it deliberately.

What It Will Cover¶

• ignore_errors: true — continue the play on this host past a failed task (rarely the right first instinct; usually failed_when is)
• failed_when: — define failure explicitly instead of relying on a module's default success/failure logic (used constantly with command/shell, see Command vs. Shell)
• any_errors_fatal: true — stop the entire play, across all hosts, the moment any single host fails
• max_fail_percentage — abort the play once more than a given percentage of hosts have failed, useful for canary-style rollouts
• How these interact with block/rescue/always

Common Mistakes¶

• Reaching for ignore_errors: true to silence a failure instead of fixing the underlying failed_when logic — this hides real problems, not just cosmetic ones.
• Not setting any_errors_fatal/max_fail_percentage on a rollout that should stop early if early hosts are already failing.

Interview Questions¶

• What's the difference between ignore_errors and failed_when?
• How would you stop an entire rollout early if 20% of hosts fail?

Next¶

Continue to Imports vs. Includes.