Summary

In this chapter, you learned about the differences between vertical scaling and horizontal scaling. We discussed options to increase an EC2 instance's specification and capacity. We then examined the AWS ELB service and how it can be used to evenly distribute incoming application traffic across a fleet of EC2 instances. You learned about the different types of ELBs and their use cases—ALBs, NLBs, GWLBs, and CLBs. We discussed how, using ELB, you can distribute the placement of EC2 instances that power your application across multiple AZs, thereby offering HA of services in case of AZ failures or outages.

Next, we examined how we can automatically scale out (add more EC2 instances to our fleet of servers that support an application) using the Amazon Auto Scaling service. Auto Scaling can help us scale out when demand increases and equally scale back in when demand drops, ensuring that you always have the right number of EC2 instances to provide the best user experience...