EKS Auto Mode [Bug]: Auto Mode was not able to create a node pool with EC2NodeClass

[sangnguyen7]

I have been able to create NodePool using the built-in NodeClass. However, it was not able to create a node pool with EC2NodeClass.

Environments:

EKS: v1.31
Auto-Mode: enabled
Karpenter Controler: No (because it's included in the Auto Mode)
Karpenter CRDs: yes (Default Auto Mode does not have EC2NodeClass installed)

Reason to use EC2NodeClass:

• Not able to EBS snapshots with the built-in eks NodeClass

=======================

EC2NodeClass.yaml

apiVersion: karpenter.k8s.aws/v1
  kind: EC2NodeClass
  metadata:
    annotations:
      meta.helm.sh/release-name: cpu-x86-karpenter
      meta.helm.sh/release-namespace: karpenter-resources
    labels:
      app.kubernetes.io/managed-by: Helm
    name: cpu-x86
  spec:
    amiFamily: Bottlerocket
    amiSelectorTerms:
    - alias: bottlerocket@latest
    blockDeviceMappings:
    - deviceName: /dev/xvda
      ebs:
        deleteOnTermination: true
        encrypted: true
        volumeSize: 100Gi
        volumeType: gp3
    detailedMonitoring: true
    metadataOptions:
      httpEndpoint: enabled
      httpProtocolIPv6: disabled
      httpPutResponseHopLimit: 2
      httpTokens: required
    role: xxx-eks-auto-20250110154059234000000002
    securityGroupSelectorTerms:
    - tags:
        aws:eks:cluster-name: xxxx
    subnetSelectorTerms:
    - tags:
        karpenter.sh/discovery: xxxx
    tags:
      Name: karpenter-cpu-x86

Nodepool.yaml

apiVersion: karpenter.sh/v1
kind: NodePool
metadata:
  annotations:
    meta.helm.sh/release-name: cpu-x86-karpenter
    meta.helm.sh/release-namespace: karpenter-resources
  labels:
    app.kubernetes.io/managed-by: Helm
  name: cpu-x86
spec:
  disruption:
    budgets:
    - nodes: 10%
    consolidateAfter: 300s
    consolidationPolicy: WhenEmpty
  limits:
    cpu: 100
    memory: 1000Gi
  template:
    metadata:
      labels:
        auto-mode/group-name: cpu-x86
        auto-mode/kind: ec2-node-class
    spec:
      expireAfter: 360h
      nodeClassRef:
        group: karpenter.k8s.aws
        kind: EC2NodeClass
        name: cpu-x86
      requirements:
      - key: karpenter.k8s.aws/instance-family
        operator: In
        values:
        - m5
      - key: karpenter.k8s.aws/instance-size
        operator: In
        values:
        - xlarge
        - 2xlarge
        - 4xlarge
        - 8xlarge
      - key: kubernetes.io/arch
        operator: In
        values:
        - amd64
      - key: kubernetes.io/os
        operator: In
        values:
        - linux
      - key: karpenter.sh/capacity-type
        operator: In
        values:
        - spot
        - on-demand
      terminationGracePeriod: 48h

Am I missing anything?

Thanks!

[mikestef9]

See EKS docs https://docs.aws.amazon.com/eks/latest/userguide/create-node-class.html

Kind is different with Auto Mode

[sangnguyen7]

Thanks @mikestef9! yes, I was able to create a NodePool using the default NodeClass kind. However, NodeClass doesn't support using EBS Snapshots with Bottlerocket as documented here: https://github.com/aws-samples/bottlerocket-images-cache/tree/main

This is why I'm trying to use EC2NodeClass on EKS Auto Mode to achieve EBS snapshot functionality.

[mikestef9]

That's not possible. Sounds like this more a feature request where you need snapshotID supported on NodeClass with Auto Mode? We've heard that from a number of users so far and evaluating adding it.

[sangnguyen7]

@mikestef9, yes that's correct. Currently, it seems NodeClass does not have that feature. And you're saying that it's not possible to use EC2NodeClass on Auto Mode ? Or do you know anyway to achieve that on an Auto Mode enabled cluster?