One of the essential features of cloud computing is scalability. Scalable infrastructures can help us scale up or down our application in no extra time. Furthermore, cloud infrastructure allows us to adapt the server requirement to the organic traffic for any web application.
If you are unsure how much power or infrastructure your application needs to stay alive, you can adopt the concept of pay-as-you-go, which means you can scale up or down anytime you want with no extra charges.
What is AWS Auto Scaling
AWS Auto Scaling automatically keeps tracking the performance of all the scalable resources, which can span various cloud services that support the application.
These resources include Elastic Compute Cloud (EC2) Auto Scaling groups, Amazon Elastic Container Service (ECS) components, EC2 Spot Fleets, DynamoDB global secondary indexes or tables, and Aurora replicas or clusters.
As demand increases, an AWS Auto Scaling service can automatically scale those resources, and as the market drops, we can mount them back down.
With the AWS Auto Scaling service, you can configure one unified scaling policy per application resource, such as an AWS CloudFormation stack or a set of resource tags.
Then, we can add each scalable resource that supports our application to the scaling plan and define the utilization targets based on which those resources should scale. You can prioritize the application availability, cost optimization, or a combination of the two.
The service also offers recommendations for scaling policies based on metrics and thresholds that are popular among AWS users. Also, it enables you to visualize resource utilization across different services in a single user interface.
AWS cloud infrastructure can scale in, out, up, and down depending on the system’s needs.
Scaling Out: Auto Scaling in AWS
Scaling Out infrastructure is also known as Horizontal Scaling. This is because we can add capacity to the web application by installing new nodes to the system to handle the traffic.
Adding more and more web servers to the application is the perfect example of AWS Scaling out.
Scaling In: Auto Scaling in AWS
It is the exact opposite of Scaling In. When our traffic goes down, we do not need the extra servers. So we remove the nodes from the system called Scaling In in AWS. Likewise, if a web application’s number of web servers is reduced, it is called Scaling In.
AWS Scaling Up
AWS Scaling Up is called Vertical Scaling in Cloud service. They are scaling up means when the resources are added to a single component or node to increase its capacity to handle the traffic or load.
If you run a WordPress website and your traffic suddenly gets high, you might need to add more CPUs to balance the traffic load. It is called Scaling Up in cloud terminology. Another example would be to increase the memory of a database server.
AWS Scaling Down
It is a form of Vertical Scaling. It is the opposite of Scaling Up. It means that when the resources are removed from a single component or node to handle decreased traffic.
Reducing the processing capacity of a component like the CPU is the exact example of Scaling Down.
Benefits of AWS Auto Scaling
The following are some advantages of AWS Auto Scaling.
Setup Scaling Quickly
AWS Auto Scaling lets us set the target utilization levels for multiple resources in a single, intuitive user interface. As a result, you can quickly see an average utilization of all your scalable resources without navigating to the other consoles.
For example, if your application uses an Amazon EC2 and Amazon DynamoDB instance, you can use AWS Auto Scaling to manage the resource provisioning for all the EC2 Auto Scaling groups and database tables in your application.
Automatically Maintain Performance
You can maintain optimal application performance and availability using AWS Auto Scaling, even when the workloads are periodic, unpredictable, or continuously changing. AWS Auto Scaling continuously monitors your applications to ensure they run at your desired performance levels.
When the demand stalks or increases, AWS Auto Scaling automatically increases the capacity of constrained resources, so you maintain a high quality of service.
Pay Only For What You Need
AWS Auto Scaling can help us to optimize our utilization and cost performances when consuming the AWS services, so you only pay for the resources you need to run the application.
When demand falls, AWS Auto Scaling will automatically eliminate any excess resource capacity, so you avoid any overspending. In addition, auto Scaling is free to use and allows us to optimize the costs of your AWS ecosystem.
Make Smart Scaling Decisions
AWS Auto Scaling lets us develop scaling plans that automate how groups of different resources respond to changes in demand. As a result, we can optimize availability and costs or balance both.
AWS Auto Scaling automatically builds all the scaling policies and sets your goals based on your choice. In addition, AWS Auto Scaling monitors our application and automatically adds or eliminates capacity from your resource groups in real-time as demands evolve.
One thing we need to understand when we are building an application is that we must develop the application in such a way that it can be scalable. Our application must be scalable if we want to take advantage of cloud scalability infrastructure.