A running EBS-backed EC2 instance has been verified to meet CloudWatch recovery requirements. Notify operators and attempt recovery when an underlying infrastructure fault keeps StatusCheckFailed_System at 1.
An alarm already selects the InstanceId, one-minute Minimum greater than 0, EvaluationPeriods=2, and DatapointsToAlarm=2. An SNS topic and confirmed notification subscription are ready. TreatMissingData=missing and the permissions needed for the actions are configured.
Choose TWO appropriate actions for this alarm.
Attach SNS notification and EC2 recover to a StatusCheckFailed_System alarm on a verified eligible instance.
Detailed explanation
Missing observations do not prove a failed System check. EC2 actions use ALARM as the trigger state; do not initiate recovery solely because data is unavailable.
Missing observations do not prove a failed System check. EC2 actions use ALARM as the trigger state; do not initiate recovery solely because data is unavailable.
Reboot restarts the instance on the same host; it is not the host-recovery operation.
Reboot restarts the instance on the same host; it is not the host-recovery operation.
A system-check failure on an eligible instance can trigger recovery onto different hardware.
A system-check failure on an eligible instance can trigger recovery onto different hardware.
CloudWatch recover supports only StatusCheckFailed_System, not the guest-side instance status check.
CloudWatch recover supports only StatusCheckFailed_System, not the guest-side instance status check.
The confirmed subscription can deliver the operational notification when the condition is met.
The confirmed subscription can deliver the operational notification when the condition is met.
Check official documentation
Compare the following points with the official documentation.
Review recovery eligibility, supported checks, one-minute Minimum with 2/2 evaluation, and preserved instance information.
Official references
What to confirm
Distinguish system-check recover from instance-check reboot and explain notification and recovery as separate actions.
Key points
- SNS notification
- EC2 recover action
- StatusCheckFailed_System
Notes
- Environment: AWS SOA-C03 exam guide and the linked AWS documentation
- Reviewed against the linked AWS documentation on 2026-10-09.
Foundation review
Match the failure signal and action
StatusCheckFailed_System indicates infrastructure issues; StatusCheckFailed_Instance indicates guest-side investigation. This recovery alarm targets the System check. Verify eligibility, running state, and permissions, then configure SNS and recover separately. EC2 actions trigger in ALARM. Use the recommended TreatMissingData=missing: INSUFFICIENT_DATA signals insufficient observations, not proof of infrastructure failure or health.
Verify infrastructure and application recovery
CloudWatch action based recovery attempts migration onto different hardware and reboots the instance. Instance ID, IP addresses, and attached EBS are retained, but RAM and instance-store data are lost. This differs from same-host reboot. Recovery does not guarantee success or application health. Check alarm/action history, EC2 status checks, and service connectivity.