Egress Inspection with AWS Gateway Load Balancer
Read the full guide on docs.beyondyou.my.idOrganizations with strict security requirements need to inspect all outbound traffic for threats, data exfiltration, and policy violations. AWS Gateway Load Balancer (GWLB) makes this possible by transparently routing traffic through security appliances without modifying application architectures.
Key Takeaways
- GWLB uses the GENEVE protocol to encapsulate and forward traffic to security appliances while preserving source/destination IPs
- Appliances can be third-party firewalls (Palo Alto, Fortinet) running in auto-scaling groups behind GWLB
- Transit Gateway route tables direct spoke VPC traffic to the GWLB endpoint in the inspection VPC
- Symmetric routing ensures return traffic flows back through the same appliance
- GWLB endpoints appear as simple route targets — no configuration changes needed in spoke VPCs
Quick Overview
The inspection architecture uses a dedicated inspection VPC containing a GWLB and a fleet of security appliances. Spoke VPC egress traffic is routed via Transit Gateway to a GWLB endpoint in the inspection VPC. The GWLB encapsulates the original packet in GENEVE and forwards it to a healthy appliance. The appliance inspects the traffic, applies security policies, and returns allowed packets through the same GWLB endpoint back to the Transit Gateway, which delivers them to their destination.
This pattern supports horizontally scalable, highly available traffic inspection with full network-level transparency.
Read the full guide: Egress Inspection with AWS Gateway Load Balancer → — includes detailed routing configurations, appliance setup, and troubleshooting flow logs.