host_key_checking has nothing to do with parallel runs so I'm not sure what you mean by that. By default Ansible will run on hosts in parallel up to the forks configured [1]. If you want to run multiple tasks at the same time the only real option is to use async with poll: 0 [2] so it runs in the background and Ansible continues onto the next task. This does have limitations and it makes it difficult to track the status or even the success of each task you run in async.
[1] - https://docs.ansible.com/ansible/latest/user_guide/playbooks_strategies.html#setting-the-number-of-forks [2] - https://docs.ansible.com/ansible/latest/user_guide/playbooks_async.html#concurrent-tasks-poll-0 -- You received this message because you are subscribed to the Google Groups "Ansible Project" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/ansible-project/d4b3ada3-9cae-457d-a07a-c07aad1c5a71%40googlegroups.com.
