Ref: https://learn.cantrill.io/courses/1820301/lectures/41301585 and https://learn.cantrill.io/courses/1820301/lectures/41301586

• Contents:

PART A - Configuring a R53 Failover Routing Policy

STEP 1: Create a Health Check for your Primary Resource

• R53 → Health checks → Create health check
• Create an endpoint health check for the EC2 application
  • UI screenshots and steps available in theory lesson
  • Endpoint can be defined with public IP address or public DNS name
    • if using IP address, be sure to use an Elastic IP address so that the address will be static even if the EC2 instance is stopped or has problems
• 💡 Health checks start with unknown status!
  • Need to gather enough info of the website first
  • Will take some time to become healthy/unhealthy

STEP 2: Create Failover Records

• R53 → Hosted zones → <SELECT_HOSTED_ZONE> → Create record
  • Quick create vs Wizard → select Wizard to be guided step-by-step
• Select a routing template in the UI
• Primary failover record configuration:
• Associate created health check to the primary failover record
• Secondary failover record configuration:
• Two failover records (primary and secondary) should now be in place, with a health check associated to the primary health record

STEP 3: Test the Failover Routing

• Simulate failure by stopping EC2 instance
  • After a few minutes, S3 website should be shown instead when querying the IP address
• Restart the EC2 instance to simulate system being recovered
  • After a few minutes, EC2 website should be shown again when querying the IP address

PART B - Configuring a R53 Private Hosted Zone