Describe in high-level how to upgrade a system on AWS with (near) zero downtime
Answer
One way is through launching a new instance. In more detail:
- Launch a new instance
- Install all the updates and applications
- Test the instance
- If all tests passed successfully, you can start using the new instance and perform the switch with the old one, in one of various ways:
- Go to route53 and update the record with the IP of the new instance
- If you are using an Elastic IP then move it to the new instance ...