Introduction to Security Groups

• Fundamental of network security in AWS
• Control how traffic is allowed into or out of our EC2 instances
• Only contain allow rules
• Can reference by IP or security groups

Deep Dive

Security groups are acting as a firewall on EC2 instances

They regulate:

1. Access to Ports
2. Authorised IP ranges (IPv4 and IPv6)
3. Control of inbound network
4. Control of outbound network

Good to know

• Can be attached to multiple instances
• Locked down to a region/VPC combination
• Does live “outside” the EC2
• Good to maintain one separate security group for SSH access
• If your application is not accessible (time out) its a security group issue
• If your application gives a “connection refused” then its an application error or its not launched