Infrastructure
Resilience
High-availability promotion path from the single-AZ baseline.
The standing footprint is a single-AZ deployment with no single points of failure inside the VPC beyond the backend instance itself. The architecture is high-availability-ready.
- Multi-AZ RDS — single-toggle promotion that adds a synchronous standby for automatic failover.
- Multi-AZ backend — add a second instance behind the same ALB once the in-memory session state is externalized.
- Multi-AZ NAT — provision a second NAT Gateway in the second public subnet.
CloudFront, S3, Cognito, Bedrock, AgentCore, SES, and the AWS managed services are themselves multi-AZ by default and require no operator action.