Add CoreDNS support into DNS controller addon image.

dns-controller/cmd/dns-controller/main.go

@@ -17,9 +17,12 @@ limitations under the License.
 package main
 
 import (
+	"bytes"
 	"flag"
 	"fmt"
+	"io"
 	"os"
+	"strings"
 
 	"github.com/golang/glog"
 	"github.com/spf13/pflag"
@@ -30,7 +33,7 @@ import (
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 	_ "k8s.io/kubernetes/federation/pkg/dnsprovider/providers/aws/route53"
-	_ "k8s.io/kubernetes/federation/pkg/dnsprovider/providers/coredns"
+	k8scoredns "k8s.io/kubernetes/federation/pkg/dnsprovider/providers/coredns"
 	_ "k8s.io/kubernetes/federation/pkg/dnsprovider/providers/google/clouddns"
 )
 
@@ -56,6 +59,9 @@ func main() {
 	watchIngress := true
 	flags.BoolVar(&watchIngress, "watch-ingress", watchIngress, "Configure hostnames found in ingress resources")
 
+	dnsServer := ""
+	flag.StringVar(&dnsServer, "dns-server", dnsServer, "DNS Server")
+
 	// Trick to avoid 'logging before flag.Parse' warning
 	flag.CommandLine.Parse([]string{})
 
@@ -87,7 +93,15 @@ func main() {
 	//	glog.Fatalf("error building extensions REST client: %v", err)
 	//}
 
-	dnsProvider, err := dnsprovider.GetDnsProvider(dnsProviderId, nil)
+	var file io.Reader
+	if dnsProviderId == k8scoredns.ProviderName {
+		var lines []string
+		lines = append(lines, "etcd-endpoints = "+dnsServer)
+		lines = append(lines, "zones = "+zones[0])
+		config := "[global]\n" + strings.Join(lines, "\n") + "\n"
+		file = bytes.NewReader([]byte(config))
+	}
+	dnsProvider, err := dnsprovider.GetDnsProvider(dnsProviderId, file)
 	if err != nil {
 		glog.Errorf("Error initializing DNS provider %q: %v", dnsProviderId, err)
 		os.Exit(1)

docs/development/vsphere-dev.md

@@ -10,7 +10,7 @@ Here is a [list of requirements and tasks](https://docs.google.com/document/d/10
 
 ## Setting up DNS
 Since vSphere doesn't have built-in DNS service, we use CoreDNS to support the DNS requirement in vSphere provider. This requires the users to setup a CoreDNS server before creating a kubernetes cluster. Please follow the following instructions to setup.
-Before the support of CoreDNS becomes stable, use env parameter "VSPHERE_DNS=coredns" to enable using CoreDNS. Or else AWS Route53 will be the default DNS service. To use Route53, follow instructions on: https://github.com/vmware/kops/blob/vsphere-develop/docs/aws.md
+**Before the support of CoreDNS becomes stable, use env parameter "VSPHERE_DNS=coredns"** to enable using CoreDNS. Or else AWS Route53 will be the default DNS service. To use Route53, follow instructions on: https://github.com/vmware/kops/blob/vsphere-develop/docs/aws.md
 
 For now we hardcoded DNS zone to skydns.local. So your cluster name should have suffix skydns.local, for example: "mycluster.skydns.local"
 
@@ -56,6 +56,17 @@ ns1.ns.dns.skydns.local. 160	IN	A	192.168.0.1
 ### Add DNS server information when create cluster
 Add ```--dns=private --vsphere-coredns-server=http://[DNS server's IP]:2379``` into the ```kops create cluster``` command line.
 
+### Use CoreDNS supported DNS Controller
+Information about DNS Controller can be found [here](https://github.com/kubernetes/kops/blob/master/dns-controller/README.md)
+Currently the DNS Controller is an add-on container and the image is from kope/dns-controller.
+Before the vSphere support is officially merged into upstream, we need to set up CoreDNS supported DNS controller manually.
+```bash
+DOCKER_REGISTRY=[your docker hub repo] make dns-controller-push
+export VSPHERE_DNSCONTROLLER_IMAGE=[your docker hub repo]
+make
+kops create cluster ...
+```
+
 ## Hacks
 
 ### Nodeup and protokube testing

upup/models/cloudup/resources/addons/dns-controller.addons.k8s.io/pre-k8s-1.6.yaml.template

@@ -28,7 +28,7 @@ spec:
       hostNetwork: true
       containers:
       - name: dns-controller
-        image: kope/dns-controller:1.6.0
+        image: {{ DnsControllerImage }}:1.6.0
         command:
 {{ range $arg := DnsControllerArgv }}
         - "{{ $arg }}"

upup/pkg/fi/cloudup/template_functions.go

@@ -36,6 +36,7 @@ import (
 	"k8s.io/kops/pkg/model/components"
 	"k8s.io/kops/upup/pkg/fi"
 	"k8s.io/kops/upup/pkg/fi/cloudup/gce"
+	"os"
 	"strings"
 	"text/template"
 )
@@ -95,6 +96,7 @@ func (tf *TemplateFunctions) AddTo(dest template.FuncMap) {
 	// TODO: Only for GCE?
 	dest["EncodeGCELabel"] = gce.EncodeGCELabel
 
+	dest["DnsControllerImage"] = tf.DnsControllerImage
 }
 
 // SharedVPC is a simple helper function which makes the templates for a shared VPC clearer
@@ -137,6 +139,7 @@ func (tf *TemplateFunctions) DnsControllerArgv() ([]string, error) {
 		argv = append(argv, "--dns=google-clouddns")
 	case fi.CloudProviderVSphere:
 		argv = append(argv, "--dns=coredns")
+		argv = append(argv, "--dns-server="+*tf.cluster.Spec.CloudConfig.VSphereCoreDNSServer)
 
 	default:
 		return nil, fmt.Errorf("unhandled cloudprovider %q", tf.cluster.Spec.CloudProvider)
@@ -160,3 +163,17 @@ func (tf *TemplateFunctions) DnsControllerArgv() ([]string, error) {
 
 	return argv, nil
 }
+
+// TODO: this is a work-around before vSphere support is getting merged into upstream kops.
+// To use CoreDNS supported DNS Controller:
+// 1. DOCKER_REGISTRY=[your docker hub repo] make dns-controller-push
+// 2. export VSPHERE_DNSCONTROLLER_IMAGE=[your docker hub repo]
+// 3. make kops and create/apply cluster
+func (tf *TemplateFunctions) DnsControllerImage() (string, error) {
+	image := os.Getenv("VSPHERE_DNSCONTROLLER_IMAGE")
+	if fi.CloudProviderID(tf.cluster.Spec.CloudProvider) != fi.CloudProviderVSphere || image == "" {
+		return "kope/dns-controller", nil
+	} else {
+		return image, nil
+	}
+}