Test if a server is reachable from host and has port open with Ansible

Question:

I want to test if the host I am provisioning can reach a specific server and connect to a specific TCP port. If it can’t the playbook should fail.

How can I do that?

There is wait_for module for this.
To check that target.host can access remote.host:8080:

- hosts: target.host
  tasks:
    - wait_for: host=remote.host port=8080 timeout=1
    - debug: msg=ok

- hosts: target.host

tasks:

- wait_for: host=remote.host port=8080 timeout=1

- debug: msg=ok

There are a lot of other examples in the documentation.