An EC2 application behind an ALB returns HTTP 500 responses.
Remove unhealthy targets from new load-balancer traffic automatically.
Which setting is most appropriate?
Configure an ALB target-group health check to detect unhealthy targets and stop routing new requests to them.
Detailed explanation
The health check evaluates the target response and prevents new requests from being sent to an unhealthy target.
The health check evaluates the target response and prevents new requests from being sent to an unhealthy target.
Cache lifetime is not a target-health decision for a load balancer.
Cache lifetime is not a target-health decision for a load balancer.
S3 object history does not determine whether an ALB target is healthy.
S3 object history does not determine whether an ALB target is healthy.
DNS record count does not monitor an HTTP response from a load-balancer target.
DNS record count does not monitor an HTTP response from a load-balancer target.
Check official documentation
Compare the following points with the official documentation.
Elastic Load Balancing target health checksの公式説明を確認する。
What to confirm
DNSヘルスチェックとALBターゲットヘルスチェックを区別できる。
Key points
- Target group
- Health check
- HTTP 500
Notes
- Environment: AWS公式SOA-C03試験ガイドとAWS公式ドキュメントの確認
- Confirm current AWS service behavior in the official documentation.
Foundation review
Target health
Routing decisions use target health rather than unrelated DNS or object-storage state.
Failure isolation
An unhealthy target can be removed from new traffic while healthy targets continue serving.