What is auto scaling in the cloud?
Auto scaling automatically adds or removes servers based on current demand. When traffic rises, the cloud starts more servers, and when it falls, it shuts some down. This keeps the app responsive during busy times and saves money during quiet times, because you only pay for what you actually use.
- Auto scaling adds or removes servers automatically based on demand.
- It keeps performance steady during spikes and saves money during quiet periods.
- Rules are based on metrics like CPU usage or request count.
How it works
You set rules, such as add a server when CPU usage stays above 70 percent, and remove one when it drops below 30 percent. The cloud watches these metrics and adjusts the number of servers for you, with no manual work.
- Handles traffic spikes without a human reacting.
- Saves money by removing idle servers.
- Usually works together with a load balancer.
Point out that auto scaling and load balancing go hand in hand. New servers are useless unless a load balancer routes traffic to them, so mentioning both shows you see the full picture.
Frequently asked questions
How does auto scaling decide when to scale?
It watches metrics such as CPU, memory, or request rate against thresholds you set, then adds or removes instances when those thresholds are crossed.
How does auto scaling save money?
It removes extra servers when demand drops, so you pay only for the capacity you actually need instead of running for peak load all the time.
Common follow up questions
Related interview questions
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