Fault tolerant web application

1. Route53 directs the traffic to the CloudFront or the application load balancer

2. The application load balancer directs the requests to the autoscaling group

3. The autoscaling houses a group of EC2 (elastic computing) which can scale in and out based on rules

4. EC2 is distributed in two availability zones (AZ) to achieve fault tolerance

5. Multi AZ master relational database is placed in one AZ

6. Multi AZ standby relational database is placed in another AZ for the fail over

7. CloudFront retrieves and caches contents from the S3

8. S3 stores the contents