SAP-C02 Design for New Solutions Practice Question

Network Topology

Refer to the exhibit. An architect is troubleshooting an EC2 instance that is not responding to health checks from an Application Load Balancer. The instance is in the 'running' state. Which of the following is the most likely cause?

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The security group is blocking the health check traffic.

The most likely cause for a running EC2 instance not responding to ALB health checks is that the security group associated with the instance is not allowing incoming health check traffic from the ALB. Option B is incorrect because the instance is in the 'running' state, not stopped. Option C is incorrect because if the instance were impaired due to an AWS issue, its status checks would fail, but the instance is running. Option D is incorrect because CPU credits affect performance but do not prevent the instance from responding to health checks; the instance would still respond even with low CPU credits.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
The security group is blocking the health check traffic.
Why this is correct
A misconfigured security group can block health checks even if the instance is running.
✗
The instance is in a stopped state.
Why it's wrong here
The output shows the instance is running, not stopped.
✗
The instance is impaired due to an AWS issue.
Why it's wrong here
Instance status checks would show impairment, but the output shows running state.
✗
The instance has exhausted its CPU credits.
Why it's wrong here
CPU credits affect performance but do not cause health check failures; the instance would still respond.

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SAP-C02 Design for New Solutions Practice Question

Why each option matters

Option-by-option breakdown

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