Add HostIPs for kubelet

pkg/kubelet/kubelet_pods.go

@@ -1732,7 +1732,7 @@ func (kl *Kubelet) generateAPIPodStatus(pod *v1.Pod, podStatus *kubecontainer.Po
 		Type:   v1.PodScheduled,
 		Status: v1.ConditionTrue,
 	})
-	// set HostIP and initialize PodIP/PodIPs for host network pods
+	// set HostIP/HostIPs and initialize PodIP/PodIPs for host network pods
 	if kl.kubeClient != nil {
 		hostIPs, err := kl.getHostIPsAnyWay()
 		if err != nil {
@@ -1746,6 +1746,13 @@ func (kl *Kubelet) generateAPIPodStatus(pod *v1.Pod, podStatus *kubecontainer.Po
 				}
 			}
 			s.HostIP = hostIPs[0].String()
+			if utilfeature.DefaultFeatureGate.Enabled(features.PodHostIPs) {
+				s.HostIPs = []v1.HostIP{{IP: s.HostIP}}
+				if len(hostIPs) == 2 {
+					s.HostIPs = append(s.HostIPs, v1.HostIP{IP: hostIPs[1].String()})
+				}
+			}
+
 			// HostNetwork Pods inherit the node IPs as PodIPs. They are immutable once set,
 			// other than that if the node becomes dual-stack, we add the secondary IP.
 			if kubecontainer.IsHostNetworkPod(pod) {

pkg/kubelet/kubelet_pods_test.go

@@ -3244,6 +3244,7 @@ func Test_generateAPIPodStatus(t *testing.T) {
 
 	tests := []struct {
 		name                                       string
+		enablePodHostIPs                           bool // enable PodHostIPs feature gate
 		pod                                        *v1.Pod
 		currentStatus                              *kubecontainer.PodStatus
 		unreadyContainer                           []string
@@ -3329,9 +3330,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					runningState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodRunning,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue},
@@ -3367,9 +3370,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					runningState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodRunning,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue},
@@ -3406,9 +3411,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					runningState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodSucceeded,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue, Reason: "PodCompleted"},
@@ -3449,9 +3456,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 				Reason:  "Test",
 				Message: "test",
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodSucceeded,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue, Reason: "PodCompleted"},
@@ -3501,9 +3510,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 				Reason:  "Test",
 				Message: "test",
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodSucceeded,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue, Reason: "PodCompleted"},
@@ -3542,9 +3553,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					waitingState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodPending,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue},
@@ -3594,11 +3607,13 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					runningState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodPending,
 				Reason:   "Test",
 				Message:  "test",
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue},
@@ -3654,9 +3669,11 @@ func Test_generateAPIPodStatus(t *testing.T) {
 					runningState("containerB"),
 				},
 			},
+			enablePodHostIPs: true,
 			expected: v1.PodStatus{
 				Phase:    v1.PodRunning,
 				HostIP:   "127.0.0.1",
+				HostIPs:  []v1.HostIP{{IP: "127.0.0.1"}, {IP: "::1"}},
 				QOSClass: v1.PodQOSBestEffort,
 				Conditions: []v1.PodCondition{
 					{Type: v1.PodInitialized, Status: v1.ConditionTrue},
@@ -3679,6 +3696,7 @@ func Test_generateAPIPodStatus(t *testing.T) {
 		for _, enablePodReadyToStartContainersCondition := range []bool{false, true} {
 			t.Run(test.name, func(t *testing.T) {
 				defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.PodDisruptionConditions, test.enablePodDisruptionConditions)()
+				defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.PodHostIPs, test.enablePodHostIPs)()
 				defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.PodReadyToStartContainersCondition, enablePodReadyToStartContainersCondition)()
 				testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
 				defer testKubelet.Cleanup()

pkg/kubelet/kubelet_test.go

@@ -109,6 +109,7 @@ func init() {
 const (
 	testKubeletHostname = "127.0.0.1"
 	testKubeletHostIP   = "127.0.0.1"
+	testKubeletHostIPv6 = "::1"
 
 	// TODO(harry) any global place for these two?
 	// Reasonable size range of all container images. 90%ile of images on dockerhub drops into this range.
@@ -232,6 +233,10 @@ func newTestKubeletWithImageList(
 							Type:    v1.NodeInternalIP,
 							Address: testKubeletHostIP,
 						},
+						{
+							Type:    v1.NodeInternalIP,
+							Address: testKubeletHostIPv6,
+						},
 					},
 					VolumesAttached: []v1.AttachedVolume{
 						{