Async and Poll¶

Why This Exists¶

A task that takes ten minutes (a large file download, a slow database migration) blocks the entire play for that host by default — async/poll lets Ansible kick it off and check back later, or fire-and-forget entirely.

What It Will Cover¶

• async: <seconds> — maximum time the task is allowed to run, in the background
• poll: <seconds> — how often Ansible checks in; poll: 0 means fire-and-forget, never check
• Checking on a fire-and-forget job later with ansible.builtin.async_status
• How async differs from real parallelism across a loop — it's about not blocking on one slow task, not about running loop iterations concurrently
• A worked example: kick off a long backup job with async/poll: 0, continue the play, and poll for completion in a later task

Common Mistakes¶

• Assuming async makes a loop run its iterations in parallel — it doesn't; it's for not blocking on a single slow task.
• Setting async without a large enough value and having the job killed mid-run once the ceiling is hit.

Interview Questions¶

• What's the difference between poll: 0 and a normal blocking task?
• How would you check on a fire-and-forget async task later in the same playbook?

Next¶

Continue to Advanced Execution.