Well-Architected architecture study
Hybrid Network Migration
A staged hybrid networking design for moving workloads to AWS while preserving routing control, DNS resolution, segmentation, and rollback paths.
On-prem network
Networking
Direct Connect Gateway
Transit Gateway
Networking
Shared services + workload VPCs
Networking
Route 53 Resolver + Network Firewall
Route 53
Problem
Hybrid migrations fail when routing, DNS, firewall policy, and rollback are treated as implementation details. The network architecture has to support staged movement without breaking existing dependencies.
Design
- Direct Connect provides primary private connectivity with VPN as failover.
- Transit Gateway centralizes VPC and on-prem routing.
- Separate route tables segment shared services, production, and non-production networks.
- Route 53 Resolver endpoints support hybrid DNS.
- AWS Network Firewall or inspection VPCs enforce egress and east-west policy.
- Migration waves move services behind explicit cutover and rollback plans.
Well-Architected lens
- Reliability: redundant connectivity, failover tests, and rollback routes.
- Security: segmentation, inspection, and DNS control.
- Operational excellence: route ownership, change windows, and runbooks.
- Cost optimization: use Direct Connect, TGW attachments, and firewall endpoints where the traffic profile justifies them.
Why it is not live here
Direct Connect, Transit Gateway, and managed firewall components have steady hourly costs and need an on-premises counterpart. The brief demonstrates the design without creating idle networking spend.