Security groups and network ACLs

In this section, we will explore security groups and network ACLs and how these protective tools work to help us keep our AWS space safe. We will also explore how to set them up correctly and understand their key differences.

Introduction to security groups

Security groups are basically a virtual firewall for your EC2 instances, providing you with the control to regulate the inbound and outbound traffic at the instance level. Each security group is built with a set of rules that control the incoming and outgoing traffic of the associated EC2 instances, allowing you to refine and implement your firewall strategy with granular precision.

By design, security groups are stateful, which means that any traffic you permit to the EC2 instance is tracked and the corresponding outbound traffic is allowed to leave the instance automatically. The same is applied in the alternative direction too, i.e., if traffic is permitted by a security group to leave...