With the default Security Group, instances from different subnets can communicate as the rules are permissive. When you assign a custom Security Group to instances, then it becomes isolated.
For further actions, you may consider blocking this person and/or reporting abuse
We're a place where coders share, stay up-to-date and grow their careers.
With the default Security Group, instances from different subnets can communicate as the rules are permissive. When you assign a custom Security Group to instances, then it becomes isolated.