Merge pull request #54166 from kubernetes/revert-52193-kube-dns-anti-affinity

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Revert "kube-dns-anti-affinity: kube-dns never-co-located-in-the-same-node"

Reverts kubernetes/kubernetes#52193

As this has slowed down scheduling of kube-dns pods significantly (fixes https://github.com/kubernetes/kubernetes/issues/54164)

/cc @bowei @MrHohn @StevenACoffman

cluster/addons/dns/kube-dns.yaml.base

@@ -84,17 +84,6 @@ spec:
       annotations:
         scheduler.alpha.kubernetes.io/critical-pod: ''
     spec:
-      affinity:
-        podAntiAffinity:
-          preferredDuringSchedulingIgnoredDuringExecution:
-          - weight: 100
-            podAffinityTerm:
-              labelSelector:
-                matchExpressions:
-                  - key: k8s-app
-                    operator: In
-                    values: ["kube-dns"]
-              topologyKey: kubernetes.io/hostname
       tolerations:
       - key: "CriticalAddonsOnly"
         operator: "Exists"

cluster/addons/dns/kube-dns.yaml.in

@@ -84,17 +84,6 @@ spec:
       annotations:
         scheduler.alpha.kubernetes.io/critical-pod: ''
     spec:
-      affinity:
-        podAntiAffinity:
-          preferredDuringSchedulingIgnoredDuringExecution:
-          - weight: 100
-            podAffinityTerm:
-              labelSelector:
-                matchExpressions:
-                  - key: k8s-app
-                    operator: In
-                    values: ["kube-dns"]
-              topologyKey: kubernetes.io/hostname
       tolerations:
       - key: "CriticalAddonsOnly"
         operator: "Exists"

cluster/addons/dns/kube-dns.yaml.sed

@@ -84,17 +84,6 @@ spec:
       annotations:
         scheduler.alpha.kubernetes.io/critical-pod: ''
     spec:
-      affinity:
-        podAntiAffinity:
-          preferredDuringSchedulingIgnoredDuringExecution:
-          - weight: 100
-            podAffinityTerm:
-              labelSelector:
-                matchExpressions:
-                  - key: k8s-app
-                    operator: In
-                    values: ["kube-dns"]
-              topologyKey: kubernetes.io/hostname
       tolerations:
       - key: "CriticalAddonsOnly"
         operator: "Exists"