add scrape port to service

cluster/addons/dns/coredns/coredns.yaml.base

@@ -161,6 +161,7 @@ metadata:
   name: kube-dns
   namespace: kube-system
   annotations:
+    prometheus.io/port: "9153"
     prometheus.io/scrape: "true"
   labels:
     k8s-app: kube-dns

cluster/addons/dns/coredns/coredns.yaml.in

@@ -161,6 +161,7 @@ metadata:
   name: kube-dns
   namespace: kube-system
   annotations:
+    prometheus.io/port: "9153"
     prometheus.io/scrape: "true"
   labels:
     k8s-app: kube-dns

cluster/addons/dns/coredns/coredns.yaml.sed

@@ -161,6 +161,7 @@ metadata:
   name: kube-dns
   namespace: kube-system
   annotations:
+    prometheus.io/port: "9153"
     prometheus.io/scrape: "true"
   labels:
     k8s-app: kube-dns

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

@@ -189,6 +189,7 @@ metadata:
   name: kube-dns
   namespace: kube-system
   annotations:
+    prometheus.io/port: "9153"
     prometheus.io/scrape: "true"
   # Without this resourceVersion value, an update of the Service between versions will yield:
   #   Service "kube-dns" is invalid: metadata.resourceVersion: Invalid value: "": must be specified for an update