SAP-C02 Continuous Improvement for Existing Solutions Practice Question

A company runs a stateless web application on an Auto Scaling group of Amazon EC2 instances behind an Application Load Balancer. The instances use a launch template with a base Amazon Machine Image and run a user data script that installs the application, which takes about 8 minutes. During a scale-out event, new instances fail the load balancer health checks for several minutes, causing 5xx errors. The company wants to reduce the time from instance launch to serving traffic without changing the application. Which solution will meet these requirements MOST cost-effectively?

⚠ Common exam trap

The trap here is assuming that a warm pool is always the most cost-effective way to reduce launch time, when a golden AMI eliminates the bootstrap delay entirely without ongoing costs.

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

✓

Create a golden Amazon Machine Image with the application pre-installed and update the launch template to use it.

Baking the application into a golden AMI removes the lengthy user data installation step, so new instances can pass health checks almost immediately after launch. This directly reduces scale-out latency and is the most cost-effective because it avoids ongoing costs of warm pools or larger instances. Other options either add cost or do not address the slow bootstrap.

Answer analysis

Option-by-option breakdown

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

✓
Create a golden Amazon Machine Image with the application pre-installed and update the launch template to use it.
Why this is correct
A golden AMI eliminates the 8-minute installation during boot, so new instances pass health checks quickly. This is the most cost-effective fix because it requires no additional running services and directly addresses the slow bootstrap. Updating the launch template ensures all new instances use the pre-baked image, reducing scale-out latency.
✗
Increase the instance size in the launch template to a larger instance type.
Why it's wrong here
A larger instance type may speed up the installation slightly, but the user data script still runs and takes minutes. It does not remove the bootstrap delay and increases cost. The scenario asks for the most cost-effective solution, and scaling up does not address the root cause of slow application installation.
✗
Configure the Auto Scaling group to use a warm pool with a large number of pre-initialized instances.
Why it's wrong here
A warm pool can reduce launch time by keeping pre-initialized instances, but it requires maintaining stopped or running instances, which adds cost. It is not the most cost-effective compared to a golden AMI, and it still relies on the same slow user data script if the pool is not pre-baked. It also adds management overhead.
✗
Enable Elastic Load Balancing cross-zone load balancing and increase the health check interval.
Why it's wrong here
Cross-zone load balancing distributes traffic across zones but does not speed up instance bootstrapping. Increasing the health check interval delays the detection of unhealthy instances, potentially worsening the user experience. Neither change reduces the time for new instances to become ready, so the 5xx errors during scale-out persist.

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SAP-C02 Continuous Improvement for Existing Solutions Practice Question

Why each option matters

Option-by-option breakdown

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