add *extensions.Deployent case

pkg/cmd/util/clientcmd/factory.go

@@ -206,6 +206,30 @@ func (f *Factory) ApproximatePodTemplateForObject(object runtime.Object) (*api.P
 		}
 		return fallback, nil
 
+	case *extensions.Deployment:
+		template := &t.Spec.Template
+
+		_, kc, err := f.Clients()
+		if err != nil {
+			return template, err
+		}
+
+		pods, err := kc.Core().Pods(t.Namespace).List(metav1.ListOptions{LabelSelector: labels.SelectorFromSet(t.Spec.Selector.MatchLabels).String()})
+		if err != nil {
+			return template, err
+		}
+
+		for i := range pods.Items {
+			pod := &pods.Items[i]
+			if template == nil || pod.CreationTimestamp.Before(template.CreationTimestamp) {
+				template = &api.PodTemplateSpec{
+					ObjectMeta: pod.ObjectMeta,
+					Spec:       pod.Spec,
+				}
+			}
+		}
+		return template, nil
+
 	default:
 		pod, err := f.AttachablePodForObject(object, 1*time.Minute)
 		if pod != nil {

pkg/oc/cli/cmd/debug.go

@@ -17,7 +17,6 @@ import (
 	"k8s.io/apimachinery/pkg/watch"
 	restclient "k8s.io/client-go/rest"
 	kapi "k8s.io/kubernetes/pkg/api"
-	"k8s.io/kubernetes/pkg/apis/extensions"
 	kclient "k8s.io/kubernetes/pkg/client/unversioned"
 	kcmd "k8s.io/kubernetes/pkg/kubectl/cmd"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
@@ -242,20 +241,10 @@ func (o *DebugOptions) Complete(cmd *cobra.Command, f *clientcmd.Factory, args [
 		return fmt.Errorf("you must identify a resource with a pod template to debug")
 	}
 
-	var template *kapi.PodTemplateSpec
-
-	// if we have 0 replicas, don't attempt to get attachable pod,
-	// instead use the deployment's pod template.
-	deployment, ok := infos[0].Object.(*extensions.Deployment)
-	if ok && deployment.Spec.Replicas == 0 {
-		template = &deployment.Spec.Template
-	} else {
-		template, err = f.ApproximatePodTemplateForObject(infos[0].Object)
-		if err != nil && template == nil {
-			return fmt.Errorf("cannot debug %s: %v", infos[0].Name, err)
-		}
+	template, err := f.ApproximatePodTemplateForObject(infos[0].Object)
+	if err != nil && template == nil {
+		return fmt.Errorf("cannot debug %s: %v", infos[0].Name, err)
 	}
-
 	if err != nil {
 		glog.V(4).Infof("Unable to get exact template, but continuing with fallback: %v", err)
 	}