Now, we will get into the fun part by creating a fully-fledged, highly available cloud environment. You will have a secure functioning data center at your fingertips in about 20 minutes. We will leverage CloudFormation and a quick start template to create a VPC that has some key elements:

• Public subnets: Resources in this subnet can be discoverable over the public internet if configured with a public IP, an attached internet gateway, and appropriate route tables. You would only want to put things such as web servers or NAT instances here.
• Private subnets: Resources in these subnets are hidden from public view. Anything outside your VPC cannot find what you put here even if it has a public IP address. For security reasons; put things such as Hadoop clusters, databases, and EC2 instances created for analytics processing purposes here.
• NAT gateways: Network Address Translation (NAT) gateways serve as an intermediary between resources in private subnets and the public internet.
• Bastion hosts: These are necessary to allow you to connect to your EC2 instances and Hadoop clusters in the private subnets.