Cross-regions failover

Route 53 is better when:

• DNS-based failover is acceptable

• You need domain-based routing

• Cost is a primary concern

• Simple configuration is preferred

• Health checks can be slower (30+ seconds)

Global Accelerator is better when:

• You need fast failover (<30 seconds)

• Static IP addresses are required

• You want to optimize network path to applications

• TCP/UDP traffic optimization is important

• Client-IP preservation is needed

• Network latency is critical

For most regional failover scenarios, Route 53 is sufficient unless you specifically need Global Accelerator's features like fast failover or static IPs.

Key cross-regional failover mechanisms in AWS:

1. S3 Cross-Region Replication (CRR)

• Automatically replicates objects to backup region

• Asynchronous replication with versioning

1. Aurora Global Database

• Sub-second replication across regions

• Promotes secondary region in <1 minute

• Managed failover process

1. DynamoDB Global Tables

• Multi-master, multi-region replication

• Active-active configuration

• Sub-second replication

1. EC2 Auto Recovery

• Monitors instance health

• Automatically recovers to new hardware

• Preserves instance ID and metadata

1. Elastic Disaster Recovery (DRS)

• Continuous replication of servers

• Sub-second RPO

• Automated failover testing

1. RDS Cross-Region Read Replicas

• Asynchronous replication

• Manual promotion to master

• Read scaling in secondary region

1. CloudFront with Origin Failover

• Automatic failover to backup origin

• Based on origin health checks

• No DNS propagation delay