Cost Effective Highly Available Monolithic Architecture¶
- Only 1 EC2 instance stays active at a time and can be accessed using an Elastic IP (static)
- If the instance goes down, ASG will start a new one in another AZ.
- The newly launched EC2 instance will issue an API call to attach the Elastic IP based on tag using the EC2 user data.
- Should not use ALB as the traffic only needs to be routed to a single instance (cost effective)
- The EC2 instance maintains state in an EBS volume (attached to an AZ). If the instance goes down, create a snapshot of the EBS volume which will be triggered on ASG Terminate lifecycle hook. Similarly, when a new instance is spun up, create a new EBS volume in the appropriate instance using the ASG Launch lifecycle hook.
Last updated: 2022-05-18