library/roles/postfix-relay: All the actions are by default disabled.

dnet-openaire: configure the puma development VM as a relay client.

postfix-relay/defaults/main.yml

@@ -1,3 +1,6 @@
+---
+# Set it to true when you want configure your machine to send email to a relay
+postfix_relay_client: False
 postfix_biff: "no"
 postfix_append_dot_mydomain: "no"
 postfix_use_relay_host: True
@@ -6,7 +9,7 @@ postfix_use_sasl_auth: True
 postfix_smtp_sasl_auth_enable: "yes"
 postfix_smtp_create_relay_user: True
 # See vars/isti-global.yml
-postfix_relay_host: smtp-relay.research-infrastructures.eu
+postfix_relay_host: smtp-relay.example.com
 postfix_relay_port: 587
 postfix_default_destination_concurrency_limit: 20
 #postfix_smtp_relay_user: smtp-user
@@ -15,7 +18,6 @@ postfix_default_destination_concurrency_limit: 20
 
 # The following options are used only whe postfix_relay_server is set to True
 postfix_relay_server: False
-#postfix_mynetworks: '{{ network.nmis }}, hash:/etc/postfix/network_table'
 postfix_mynetworks: hash:/etc/postfix/network_table
 postfix_interfaces: all
 postfix_inet_protocols: all

postfix-relay/tasks/main.yml

@@ -1,6 +1,9 @@
 ---
 - include: smtp-common-packages.yml
+  when: postfix_relay_client
 - include: smtp-sasl-auth.yml
-  when: postfix_use_sasl_auth
+  when:
+    - postfix_use_sasl_auth
+    - postfix_relay_client
 - include: postfix-relay-server.yml
   when: postfix_relay_server