allow_duplicates & Role Idempotency
Control repeated role execution.
Roles Run Once by Default
If two roles both depend on a common role, Ansible is smart: it runs common only once, not twice, during a single play.
Why Dedup Exists
This deduplication stops shared setup roles from repeating expensive work, like re-running a base hardening role for every app role.
All lessons in this course
- Role Dependencies in meta/main.yml
- defaults vs vars: The Override Order
- include_role & import_role at Runtime
- allow_duplicates & Role Idempotency