Effective DevOps with AWS

Using Auto Scaling groups to scale web servers

In the last chapter, we created our web server generic role using CloudFormation. When used, the template creates a single EC2 instance. We are going to do two things: replace the section that creates the EC2 instance in favor of creating an Auto Scaling group and add a section to create an Elastic Load Balancer (ELB) that will serve as our new entry point to our application.

Combining ELB and Auto Scaling groups creates a very robust architecture. While at the administrator level, an ELB instance looks like a single entity, under the hood, AWS will in fact provision multiple resources to handle possible failures and auto-scale the resources to handle any surge in traffic. In addition, a number ...