dont specify default for port, allow ssh/config (#74526)

* dont specify default for port, allow ssh/config

 also added general note on how defaults work.

Co-authored-by: Abhijeet Kasurde <akasurde@redhat.com>
Co-authored-by: Sam Doran <sdoran@redhat.com>

changelogs/fragments/ssh_port_default_fix.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - Remove 'default' from ssh plugin as we want to rely on default from ssh itself or ssh/config.

lib/ansible/plugins/connection/ssh.py

@@ -19,6 +19,9 @@ DOCUMENTATION = '''
     extends_documentation_fragment:
         - connection_pipelining
     version_added: historical
+    notes:
+        - Many options default to 'None' here but that only means we don't override the ssh tool's defaults and/or configuration.
+          For example, if you specify the port in this plugin it will override any C(Port) entry in your C(.ssh/config).
     options:
       host:
           description: Hostname/ip to connect to.
@@ -181,7 +184,6 @@ DOCUMENTATION = '''
       port:
           description: Remote port to connect to.
           type: int
-          default: 22
           ini:
             - section: defaults
               key: remote_port

test/integration/targets/connection_ssh/check_ssh_defaults.yml

@@ -0,0 +1,29 @@
+- hosts: ssh
+  gather_facts: false
+  vars:
+    ansible_connection: ssh
+    ansible_ssh_timeout: 10
+  tasks:
+    - name: contain the maddness
+      block:
+        - name: test all is good
+          ping:
+
+        - name: start the fun
+          meta: reset_connection
+
+        - name: now test we can use wrong port from ssh/config
+          ping:
+          ignore_unreachable: True
+          vars:
+            ansible_ssh_args: "-F {{playbook_dir}}/files/port_overrride_ssh.cfg"
+          register: expected
+
+        - name: check all is as expected
+          assert:
+            that:
+              - expected['unreachable']|bool
+              - "'2222' in expected['msg']"
+      always:
+        - name: make sure we don't cache the bad connection
+          meta: reset_connection

test/integration/targets/connection_ssh/files/port_overrride_ssh.cfg

@@ -0,0 +1,2 @@
+Host *
+	Port 2222

test/integration/targets/connection_ssh/runme.sh

@@ -65,3 +65,6 @@ fi
 ANSIBLE_SCP_IF_SSH=true ./posix.sh "$@" "${scp_args[@]}"
 # piped
 ANSIBLE_SSH_TRANSFER_METHOD=piped ./posix.sh "$@"
+
+# test config defaults override
+ansible-playbook check_ssh_defaults.yml "$@" -i test_connection.inventory