Multi-AZ Deployment on AWS

Every production workload spans multiple Availability Zones.

Example

Availability Zone A

Patient Portal

Lambda

Aurora Writer

EC2

────────────────────────

Availability Zone B

Patient Portal

Lambda

Aurora Reader

EC2

────────────────────────

Automatic Failover

If one Availability Zone fails, patient services remain available.

Networking

Instead of directly connecting VPCs,

the organization uses:

AWS Transit Gateway

AWS PrivateLink

Interface VPC Endpoints

Gateway Endpoints

Route 53 Resolver

Internal Application Load Balancers

Network Load Balancers

AWS Network Firewall

This creates a hub-and-spoke architecture with centralized routing and inspection.