Answer: Create an Auto Scaling group that has a scheduled action.

## Explanation **Correct Answer: B - Create an Auto Scaling group that has a scheduled action.** **Why this is the correct answer:** 1. **Predictable, recurring workload**: The workload runs every Friday evening, which is a predictable pattern. Auto Scaling scheduled actions are specifically designed for predictable scaling patterns. 2. **Least operational overhead**: Scheduled actions require minimal ongoing management once configured. The scaling happens automatically based on the schedule without human intervention. 3. **Meets all requirements**: - Maintains 2 instances normally - Scales to 6 instances every Friday - Runs in two Availability Zones for high availability **Analysis of other options:** **A. Create a reminder in Amazon EventBridge to scale the instances.** - While EventBridge can trigger scaling events, this would require additional Lambda functions or automation to actually scale the instances, adding complexity. - A reminder alone doesn't scale instances - it just notifies someone to take action. - Higher operational overhead than scheduled actions. **C. Create an Auto Scaling group that uses manual scaling.** - Requires someone to manually adjust the desired capacity every Friday. - Higher operational overhead as it needs human intervention each week. - Prone to human error and forgetting to scale. **D. Create an Auto Scaling group that uses automatic scaling.** - Automatic scaling typically uses CloudWatch metrics (CPU, memory, etc.) to scale. - This workload has a predictable schedule, not metric-based triggers. - Could lead to unnecessary scaling or not scaling at the right time if metrics don't align with the Friday workload. - More complex to configure correctly for this specific use case. **Key AWS Concepts:** - **Auto Scaling Scheduled Actions**: Allow you to scale your Auto Scaling group based on a schedule, perfect for predictable workload patterns. - **Auto Scaling Groups**: Automatically distribute instances across multiple Availability Zones for high availability. - **Desired Capacity**: The number of instances that should be running in the Auto Scaling group at any time. **Implementation Steps:** 1. Create an Auto Scaling group with min=2, max=6, desired=2 2. Configure a scheduled action to scale to 6 instances every Friday evening 3. Configure another scheduled action to scale back to 2 instances after the workload completes 4. Ensure the Auto Scaling group spans two Availability Zones for resilience

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