Code review comments and added logs

Author: Priya Wadhwa

Diff for: cmd/minikube/cmd/config/validations.go

@@ -136,7 +136,11 @@ func IsContainerdRuntime(_, _ string) error {
 	if config.KubernetesConfig.ContainerRuntime != constants.ContainerdRuntime {
 		return fmt.Errorf(`This addon can only be enabled with the containerd runtime backend.
 
-To enable this backend, please start minikube again with the following flags:
+To enable this backend, please first stop minikube with
+
+minikube stop
+
+and then start minikube again with the following flags:
 
 minikube start --container-runtime=containerd  --docker-opt containerd=/var/run/containerd/containerd.sock --network-plugin=cni`)
 	}

Diff for: pkg/gvisor/disable.go

@@ -32,7 +32,7 @@ func Disable() error {
 	if err := os.Remove(filepath.Join(nodeDir, constants.ContainerdConfigTomlPath)); err != nil {
 		return errors.Wrapf(err, "removing %s", constants.ContainerdConfigTomlPath)
 	}
-	log.Printf("Storing default config.toml at %s", constants.ContainerdConfigTomlPath)
+	log.Printf("Restoring default config.toml at %s", constants.ContainerdConfigTomlPath)
 	if err := mcnutils.CopyFile(filepath.Join(nodeDir, constants.StoredContainerdConfigTomlPath), filepath.Join(nodeDir, constants.ContainerdConfigTomlPath)); err != nil {
 		return errors.Wrap(err, "reverting back to default config.toml")
 	}

Diff for: test/integration/addons_test.go

@@ -22,6 +22,7 @@ import (
 	"bufio"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"net"
 	"net/http"
 	"net/url"
@@ -191,11 +192,13 @@ func testGvisor(t *testing.T) {
 	t.Log("enabling gvisor addon")
 	minikubeRunner.RunCommand("addons enable gvisor", true)
 	t.Log("waiting for gvisor controller to come up")
-	if err := util.WaitForGvisorControllerRunning(); err != nil {
+	if err := util.WaitForGvisorControllerRunning(t); err != nil {
 		// Print out logs from controller
-		if _, err := kubectlRunner.RunCommand([]string{"get", "pods", "--all-namespaces"}); err != nil {
+		out, err := kubectlRunner.RunCommand([]string{"get", "pods", "--all-namespaces"})
+		if err != nil {
 			t.Errorf("error getting all pods %v", err)
 		}
+		log.Print(string(out))
 		if _, err := kubectlRunner.RunCommand([]string{"logs", "gvisor", "-n", "kube-system"}); err != nil {
 			t.Errorf("error getting gvisor logs: %v", err)
 		}

Diff for: test/integration/util/util.go

@@ -127,7 +127,7 @@ func (m *MinikubeRunner) Start() {
 	switch r := m.Runtime; r {
 	case constants.ContainerdRuntime:
 		// TODO: priyawadhwa@ remove iso url once updated iso is being used in integration tests
-		containerdFlags := "--container-runtime=containerd --network-plugin=cni --docker-opt containerd=/var/run/containerd/containerd.sock --iso-url=https://storage.googleapis.com/minikube-iso/minikube.iso"
+		containerdFlags := "--container-runtime=containerd --network-plugin=cni --docker-opt containerd=/var/run/containerd/containerd.sock --iso-url=https://storage.googleapis.com/gvisor-preview/minikube.iso"
 		m.RunCommand(fmt.Sprintf("start %s %s %s", m.StartArgs, m.Args, containerdFlags), true)
 	default:
 		m.RunCommand(fmt.Sprintf("start %s %s", m.StartArgs, m.Args), true)
@@ -300,7 +300,7 @@ func WaitForIngressDefaultBackendRunning(t *testing.T) error {
 }
 
 // WaitForGvisorControllerRunning waits for the gvisor controller pod to be running
-func WaitForGvisorControllerRunning() error {
+func WaitForGvisorControllerRunning(t *testing.T) error {
 	client, err := commonutil.GetClient()
 	if err != nil {
 		return errors.Wrap(err, "getting kubernetes client")
@@ -341,7 +341,7 @@ func WaitForUntrustedNginxRunning() error {
 	return nil
 }
 
-// WaitForFailedCreatePodSandBoxEvent waits for a FailedCreatePodSandBox event to show appear
+// WaitForFailedCreatePodSandBoxEvent waits for a FailedCreatePodSandBox event to appear
 func WaitForFailedCreatePodSandBoxEvent() error {
 	client, err := commonutil.GetClient()
 	if err != nil {