Ops needs proactive detection when the login page breaks — a scripted check hitting the site every 5 minutes from outside the VPC, alerting before users report it. Which feature?
A.CloudWatch Synthetics canaries
External scripted probes = canaries. Correct.
B.CloudWatch metric alarms
Metric alarms react to emitted metrics — nothing hits the endpoint externally.
C.Application Load Balancer health checks
Health checks measure instance liveness, not page-level user journeys.
D.AWS Config rules
Config audits resource configuration, not endpoint availability.
Why this answer
Synthetics canaries are scheduled Lambda scripts that simulate user journeys against endpoints from outside your infra — the proactive 'is the site actually working' monitor. ALB health checks test instances, not the end-user experience.
Correct answer: A · Last reviewed 2026-11-05
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