Este é um problema conhecido atualmente com o EKS. Aqui está a minha resposta do suporte (parcialmente omitido):
Unfortunately, the EKS control plane currently has issues with the metrics-server aggregator. The EKS service team are working to these issues to bring metric-server support to the Control Plane.
As soon as this feature gets released, it should be publicly announced in either one of the following links:
- AWS blogs: https://blogs.amazon.com/
- What's New: https://aws.amazon.com/new/
- AWS Release Notes: https://aws.amazon.com/releasenotes/
I have indicated your interest in this issue and I will advocate for a solution on your behalf.
Espero que eles resolvam isso em breve.