Cluster Autoscaler > Karpenter > Blueprints - Which is the best approach?

[brunobritodev]

Describe the Problem

tl;dr: There is a lack of clarity about which terraform module we should use.

In the EKS Best Practices > Cluster Autoscaler > Karpenter, under the section Karpenter Blueprints, a link is provided to karpenter-blueprints on GitHub. The repository's demo utilizes the aws-ia/eks-blueprints-addons/aws module, which currently does not support POD Identity Association. This limitation is tracked in an open issue.

On the other hand, the Karpenter.sh website recommends using the Amazon EKS Blueprints for Terraform, which redirects to the documentation for terraform-aws-eks-blueprints.

The docs provides two setup recommendations:

• With Fargate
• With Managed Node Groups

Both approaches utilize the terraform-aws-modules/eks/aws//modules/karpenter component.

A review of the motivations for migrating from v4 to v5 of terraform-aws-eks-blueprints reveals that the team plans to discontinue support for certain components. They now recommend transitioning to the terraform-aws-eks module for future-proofing.

Summary

• EKS Best Practices: References a repository that uses EKS version 1.30 and a Karpenter module lacking POD Identity Association support.
• Karpenter.sh: Points to a newer repository with a Karpenter module compatible with all the latest EKS features.

The primary issue is the lack of clarity about which module should be adopted, as both official documentations provide ambiguous guidance on this decision.

My Suggestion:
Actually following the recommendations from Karpenter.sh is the best approach. This ensures compatibility with the latest EKS features.