make kube-dns work again

deployments/kubedns.yaml

@@ -15,31 +15,34 @@
 apiVersion: extensions/v1beta1
 kind: Deployment
 metadata:
-  name: kube-dns-v20
+  name: kube-dns
   namespace: kube-system
   labels:
     k8s-app: kube-dns
-    version: v20
     kubernetes.io/cluster-service: "true"
 spec:
-  replicas: 2
+  # replicas: not specified here:
+  # 1. In order to make Addon Manager do not reconcile this replicas parameter.
+  # 2. Default is 1.
+  # 3. Will be tuned in real time if DNS horizontal auto-scaling is turned on.
+  strategy:
+    rollingUpdate:
+      maxSurge: 10%
+      maxUnavailable: 0
   selector:
     matchLabels:
       k8s-app: kube-dns
-      version: v20
   template:
     metadata:
       labels:
         k8s-app: kube-dns
-        version: v20
-        kubernetes.io/cluster-service: "true"
       annotations:
         scheduler.alpha.kubernetes.io/critical-pod: ''
         scheduler.alpha.kubernetes.io/tolerations: '[{"key":"CriticalAddonsOnly", "operator":"Exists"}]'
     spec:
       containers:
       - name: kubedns
-        image: gcr.io/google_containers/kubedns-amd64:1.8
+        image: gcr.io/google_containers/kubedns-amd64:1.9
         resources:
           # TODO: Set memory limits when we've profiled the container for large
           # clusters, then set request = limit to keep this container in
@@ -69,9 +72,15 @@ spec:
           initialDelaySeconds: 3
           timeoutSeconds: 5
         args:
-        # command = "/kube-dns"
-        - --domain=cluster.local
+        - --domain=cluster.local.
         - --dns-port=10053
+        - --config-map=kube-dns
+        # This should be set to v=2 only after the new image (cut from 1.5) has
+        # been released, otherwise we will flood the logs.
+        - --v=0
+        env:
+        - name: PROMETHEUS_PORT
+          value: "10055"
         ports:
         - containerPort: 10053
           name: dns-local
@@ -79,6 +88,9 @@ spec:
         - containerPort: 10053
           name: dns-tcp-local
           protocol: TCP
+        - containerPort: 10055
+          name: metrics
+          protocol: TCP
       - name: dnsmasq
         image: gcr.io/google_containers/kube-dnsmasq-amd64:1.4
         livenessProbe:
@@ -102,6 +114,32 @@ spec:
         - containerPort: 53
           name: dns-tcp
           protocol: TCP
+        # see: https://github.com/kubernetes/kubernetes/issues/29055 for details
+        resources:
+          requests:
+            cpu: 150m
+            memory: 10Mi
+      - name: dnsmasq-metrics
+        image: gcr.io/google_containers/dnsmasq-metrics-amd64:1.0
+        livenessProbe:
+          httpGet:
+            path: /metrics
+            port: 10054
+            scheme: HTTP
+          initialDelaySeconds: 60
+          timeoutSeconds: 5
+          successThreshold: 1
+          failureThreshold: 5
+        args:
+        - --v=2
+        - --logtostderr
+        ports:
+        - containerPort: 10054
+          name: metrics
+          protocol: TCP
+        resources:
+          requests:
+            memory: 10Mi
       - name: healthz
         image: gcr.io/google_containers/exechealthz-amd64:1.2
         resources:
@@ -109,6 +147,10 @@ spec:
             memory: 50Mi
           requests:
             cpu: 10m
+            # Note that this container shouldn't really need 50Mi of memory. The
+            # limits are set higher than expected pending investigation on #29688.
+            # The extra memory was stolen from the kubedns container to keep the
+            # net memory requested by the pod constant.
             memory: 50Mi
         args:
         - --cmd=nslookup kubernetes.default.svc.cluster.local 127.0.0.1 >/dev/null