Merge pull request kubernetes#128359 from matteriben/disable-caching-for-authoritative-zone

disable caching for authoritative zone to comply with rfc-1035 section 6.1.2

Author: k8s-ci-robot

cmd/kubeadm/app/phases/addons/dns/dns_test.go

@@ -184,7 +184,10 @@ func TestCreateCoreDNSAddon(t *testing.T) {
     forward . /etc/resolv.conf {
        max_concurrent 1000
     }
-    cache 30
+    cache 30 {
+       disable success cluster.local
+       disable denial cluster.local
+    }
     loop
     reload
     loadbalance
@@ -228,7 +231,10 @@ func TestCreateCoreDNSAddon(t *testing.T) {
     forward . /etc/resolv.conf {
        max_concurrent 1000
     }
-    cache 30
+    cache 30 {
+       disable success cluster.local
+       disable denial cluster.local
+    }
     loop
     reload
     loadbalance
@@ -314,7 +320,10 @@ func TestCreateCoreDNSAddon(t *testing.T) {
     forward . /etc/resolv.conf {
        max_concurrent 1000
     }
-    cache 30
+    cache 30 {
+       disable success cluster.local
+       disable denial cluster.local
+    }
     loop
     reload
     loadbalance

cmd/kubeadm/app/phases/addons/dns/manifests.go

@@ -178,6 +178,11 @@ data:
            max_concurrent 1000
         }
         cache 30
+        {{- if .DNSDomain }} {
+           disable success {{ .DNSDomain }}
+           disable denial {{ .DNSDomain }}
+        }
+        {{- end }}
         loop
         reload
         loadbalance