Web-tier load changes significantly during the day.
Adjust the number of instances automatically using average CPU as a signal.
Choose TWO appropriate design elements.
An EC2 Auto Scaling target-tracking policy can follow a metric such as average CPU, while group capacity limits define the allowed range.
Detailed explanation
Security groups control network permissions and do not scale capacity.
Security groups control network permissions and do not scale capacity.
Capacity boundaries control how far the group can scale as demand changes.
Capacity boundaries control how far the group can scale as demand changes.
Fixed capacity cannot respond to demand and limits resilience and performance.
Fixed capacity cannot respond to demand and limits resilience and performance.
Target tracking adjusts capacity to move the selected metric toward a target value.
Target tracking adjusts capacity to move the selected metric toward a target value.
Check official documentation
Compare the following points with the official documentation.
EC2 Auto Scalingのターゲット追跡とグループ容量の公式説明を確認する。
What to confirm
スケーリング指標と容量境界をAuto Scalingへ対応付けられる。
Key points
- Target tracking
- Auto Scaling group
- Minimum and maximum capacity
Notes
- Environment: AWS公式EC2 Auto Scalingドキュメントの確認
- Confirm current AWS service behavior and architecture guidance in the official documentation.
Foundation review
Feedback control
Target tracking responds to a metric, while min/max settings protect against unbounded or insufficient capacity.
Network versus capacity
Security groups permit traffic but do not decide how many instances exist.