How do I enable communication between virtual machines in a security group?
Security groups allow for grouping of access rules but do not automatically enable virtual machines to communicate with one another.
You can enable communication within a security group by using a 'Group Access' rule. Using 'Group Access' rules will allow you to automatically enable communication between virtual machines without requiring you to manually enter and manage IP address authorized to a security group.
To enable a 'Group Access' rule visit the details page for the security group you want to enable. An option for 'Group Access' rules is available in the top right area of the side menu.