linkerd multicluster link --ha generates invalid deployment spec

[Hexcles]

What is the issue?

I was trying out the new HA mode with linkerd multicluster --ha and couldn't apply the generated specs with kubectl.

How can it be reproduced?

linkerd --context=foo multicluster link --cluster-name foo --ha | kubectl --context=bar apply -f -

Logs, error output, etc

error: error validating "STDIN": error validating data: ValidationError(Deployment.spec.template.spec): unknown field "podAntiAffinity" in io.k8s.api.core.v1.PodSpec; if you choose to ignore these errors, turn validation off with --validate=false

The relevant part of the spec is

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    linkerd.io/extension: multicluster
    component: service-mirror
    mirror.linkerd.io/cluster-name: foo
  name: linkerd-service-mirror-foo
  namespace: linkerd-multicluster
spec:
  replicas: 3
  selector:
    matchLabels:
      component: linkerd-service-mirror
      mirror.linkerd.io/cluster-name: foo
  strategy:
    rollingUpdate:
      maxUnavailable: 1
  template:
    metadata:
      annotations:
        linkerd.io/inject: enabled
        cluster-autoscaler.kubernetes.io/safe-to-evict: "true"
        config.alpha.linkerd.io/proxy-wait-before-exit-seconds: "0"
      labels:
        linkerd.io/extension: multicluster
        component: linkerd-service-mirror
        mirror.linkerd.io/cluster-name: foo
    spec:
      podAntiAffinity:
        preferredDuringSchedulingIgnoredDuringExecution:
        - podAffinityTerm:
            labelSelector:
              matchExpressions:
              - key: mirror.linkerd.io/cluster-name
                operator: In
                values:
                - foo
            topologyKey: topology.kubernetes.io/zone
          weight: 100
        requiredDuringSchedulingIgnoredDuringExecution:
        - labelSelector:
            matchExpressions:
            - key: mirror.linkerd.io/cluster-name
              operator: In
              values:
              - foo
          topologyKey: kubernetes.io/hostname
...

output of linkerd check -o short

Status check results are √

Environment

• Kubernetes 1.24
• EKS
• Linux
• Linkerd 2.14.3

Possible solution

Looking at https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.24/#podspec-v1-core, podAntiAffinity only exists under spec.affinity, so there might be something wrong with this helm chart:

linkerd2/multicluster/charts/linkerd-multicluster-link/templates/service-mirror.yaml

Lines 123 to 126 in 4018b2f

	{{- if .Values.enablePodAntiAffinity -}}
	{{- $local := dict "label" "mirror.linkerd.io/cluster-name" "component" .Values.targetClusterName -}}
	{{- include "linkerd.pod-affinity" $local | nindent 6 -}}
	{{- end }}

Additional context

No response

Would you like to work on fixing this bug?

None