Understanding AWS Auto Scaling
Auto Scaling, which is a subset of the Amazon EC2 service, revolves around automatically provisioning and managing your EC2 instances without the need for any manual intervention. The Auto Scaling service can be used to constantly maintain a fixed number of servers at any one time across one or more Availability Zones (AZs) within an Amazon Region. The service also provides you elasticity in that it can scale up to meet spikes of demand that your customers or applications present without constantly monitoring the system.
It does this by tapping into the power of a complementary service, Amazon CloudWatch. It watches a metric such as Central Processing Unit (CPU) utilization on an instance and makes sure that if it rises above 80 percent, meaning that 80 percent of the available CPU of the instance is being used for a specific time, such as 5 minutes, a scale-out event will then occur. This helps ease the load on this particular instance and should...
