Node Affinity

kubectl delete deployment -n workshop inflate
kubectl delete nodepools.karpenter.sh default
kubectl delete ec2nodeclasses.karpenter.k8s.aws default

mkdir ~/environment/karpenter
cd ~/environment/karpenter
cat <<EoF> nodeaffinity.yaml
apiVersion: karpenter.sh/v1beta1
kind: NodePool
metadata:
  creationTimestamp: null
  name: default
spec:
  disruption:
    consolidateAfter: 30s
    consolidationPolicy: WhenEmpty
    expireAfter: Never
  limits:
    cpu: "10"
  template:
    metadata:
      labels:
        eks-immersion-team: my-team
    spec:
      # References cloud provider-specific custom resource, see your cloud provider specific documentation
      nodeClassRef:
        name: default

      # Requirements that constrain the parameters of provisioned nodes.
      # These requirements are combined with pod.spec.affinity.nodeAffinity rules.
      # Operators { In, NotIn } are supported to enable including or excluding values
      requirements:
        - key: "karpenter.k8s.aws/instance-category"
          operator: In
          values: ["c", "m", "r"]
        - key: "kubernetes.io/arch"
          operator: In
          values: ["amd64"]
        - key: "karpenter.sh/capacity-type" # If not included, the webhook for the AWS cloud provider will default to on-demand
          operator: In
          values: ["on-demand"]

---
apiVersion: karpenter.k8s.aws/v1beta1
kind: EC2NodeClass
metadata:
  name: default
spec:
  amiFamily: AL2
  role: "KarpenterNodeRole-${CLUSTER_NAME}"
  securityGroupSelectorTerms:
  - tags:
      alpha.eksctl.io/cluster-name: $CLUSTER_NAME
  subnetSelectorTerms:
  - tags:
      alpha.eksctl.io/cluster-name: $CLUSTER_NAME
  tags:
    intent: apps
    managed-by: karpenter
EoF

kubectl apply -f nodeaffinity.yaml

cd ~/environment/karpenter
cat <<EoF> constraint-deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: inflate
spec:
  replicas: 3
  selector:
    matchLabels:
      app: inflate
  template:
    metadata:
      labels:
        app: inflate
    spec:
      affinity: 
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                - key: "node.kubernetes.io/instance-type"
                  operator: "In"
                  values: ["m6a.xlarge"]
      terminationGracePeriodSeconds: 0
      containers:
        - name: inflate
          image: public.ecr.aws/eks-distro/kubernetes/pause:3.7
          resources:
            requests:
              cpu: 1
      nodeSelector:
        eks-immersion-team: my-team
EoF

kubectl apply -f constraint-deploy.yaml