aws hostname guidelines

Author: nasark

installing_on_aws/index.md

@@ -7,6 +7,8 @@
 
 {% include configuration.md %}
 
+**Note:** When configuring messaging, please refer to https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-naming.html on hostname guidelines i.e. inclusion of `.ec2.internal` or `.compute.internal` in the hostname
+
 {% include initial-login.md %}
 
 # Appendix