How to Configure Horizontal Pod Autoscaler (HPA) on EKS Fargate with Metrics Server - Getting 403 Forbidden Error

Question

I am trying to configure the Horizontal Pod Autoscaler (HPA) on my EKS Fargate setup, but I am running into an issue where the Metrics Server is returning a 403 Forbidden error when it tries to scrape metrics from my Fargate pods.

What I've done so far: I have a working EKS Fargate cluster. I have installed the Metrics Server on EKS. I have configured the Horizontal Pod Autoscaler (HPA) based on CPU utilization. I ensured that the Metrics Server has the correct arguments to scrape pod-level metrics. Metrics Server Configuration: I have updated the Metrics Server deployment with the following arguments:

yaml Copy Edit args:

• --cert-dir=/tmp
• --secure-port=10250
• --metric-resolution=15s
• --kubelet-insecure-tls
• --kubelet-preferred-address-types=InternalIP
• The Issue: Despite the above configuration, I am getting a 403 Forbidden error in the Metrics Server logs when trying to scrape metrics:

Troubleshooting Steps Taken: I checked the Metrics Server logs and verified that the server is running securely on port 4443. I verified that the HPA is correctly set up to scale based on CPU utilization. Error Details: The key error I see is the 403 Forbidden:

This indicates that the Metrics Server is trying to scrape the Kubelet, but the request is being blocked.