I have heard that using an Elastic IP is generally considered a poor architectural design. Why so ? Why isn't an Elastic IP a suggested approach?

Question

I have heard that using an Elastic IP is generally considered a poor architectural design. Why so ? Why isn't an Elastic IP a suggested approach ?

Answer 1

In general, applications should avoid referring to IP addresses. This limits their ability to point to different resources when things are changed.

Instead, it is better to use a DNS Name, which can be changed to point to a different IP address if anything changes.

Applications that run on a single Amazon EC2 instance might later grow to use multiple EC2 instances, fronted with a Load Balancer. In this situation, the DNS Name can be changed to point to a load balancer rather than a single IP address.

While Elastic IP addresses can be moved between instances, they are still associated with only a single region, and only for use within AWS, so they are not totally flexible.

The only time that an IP address is normally required is for whitelisting with external services that want to receive requests from a specific IP address.