Merge pull request #86493 from aojea/kubeadmAddress

kubeadm: use bind-address instead of address to configure the http probes

cmd/kubeadm/app/util/staticpod/utils.go

@@ -38,11 +38,11 @@ import (
 )
 
 const (
-	// kubeControllerManagerAddressArg represents the address argument of the kube-controller-manager configuration.
+	// kubeControllerManagerBindAddressArg represents the bind-address argument of the kube-controller-manager configuration.
-	kubeControllerManagerAddressArg = "address"
+	kubeControllerManagerBindAddressArg = "bind-address"
 
-	// kubeSchedulerAddressArg represents the address argument of the kube-scheduler configuration.
+	// kubeSchedulerBindAddressArg represents the bind-address argument of the kube-scheduler configuration.
-	kubeSchedulerAddressArg = "address"
+	kubeSchedulerBindAddressArg = "bind-address"
 )
 
 // ComponentPod returns a Pod object from the container and volume specifications
@@ -244,7 +244,7 @@ func GetAPIServerProbeAddress(endpoint *kubeadmapi.APIEndpoint) string {
 	// probes do not support the Downward API we cannot dynamically set the advertise address to
 	// the node's IP. The only option then is to use localhost.
 	if endpoint != nil && endpoint.AdvertiseAddress != "" {
-		return endpoint.AdvertiseAddress
+		return getProbeAddress(endpoint.AdvertiseAddress)
 	}
 
 	return "127.0.0.1"
@@ -252,16 +252,16 @@ func GetAPIServerProbeAddress(endpoint *kubeadmapi.APIEndpoint) string {
 
 // GetControllerManagerProbeAddress returns the kubernetes controller manager probe address
 func GetControllerManagerProbeAddress(cfg *kubeadmapi.ClusterConfiguration) string {
-	if addr, exists := cfg.ControllerManager.ExtraArgs[kubeControllerManagerAddressArg]; exists {
+	if addr, exists := cfg.ControllerManager.ExtraArgs[kubeControllerManagerBindAddressArg]; exists {
-		return addr
+		return getProbeAddress(addr)
 	}
 	return "127.0.0.1"
 }
 
 // GetSchedulerProbeAddress returns the kubernetes scheduler probe address
 func GetSchedulerProbeAddress(cfg *kubeadmapi.ClusterConfiguration) string {
-	if addr, exists := cfg.Scheduler.ExtraArgs[kubeSchedulerAddressArg]; exists {
+	if addr, exists := cfg.Scheduler.ExtraArgs[kubeSchedulerBindAddressArg]; exists {
-		return addr
+		return getProbeAddress(addr)
 	}
 	return "127.0.0.1"
 }
@@ -321,3 +321,16 @@ func ManifestFilesAreEqual(path1, path2 string) (bool, error) {
 
 	return bytes.Equal(content1, content2), nil
 }
+
+// getProbeAddress returns a valid probe address.
+// Kubeadm uses the bind-address to configure the probe address. It's common to use the
+// unspecified address "0.0.0.0" or "::" as bind-address when we want to listen in all interfaces,
+// however this address can't be used as probe #86504.
+// If the address is an unspecified address getProbeAddress returns empty,
+// that means that kubelet will use the PodIP as probe address.
+func getProbeAddress(addr string) string {
+	if addr == "0.0.0.0" || addr == "::" {
+		return ""
+	}
+	return addr
+}

cmd/kubeadm/app/util/staticpod/utils_test.go

@@ -72,6 +72,20 @@ func TestGetAPIServerProbeAddress(t *testing.T) {
 			},
 			expected: "2001:abcd:bcda::1",
 		},
+		{
+			desc: "filled in 0.0.0.0 AdvertiseAddress endpoint returns empty",
+			endpoint: &kubeadmapi.APIEndpoint{
+				AdvertiseAddress: "0.0.0.0",
+			},
+			expected: "",
+		},
+		{
+			desc: "filled in :: AdvertiseAddress endpoint returns empty",
+			endpoint: &kubeadmapi.APIEndpoint{
+				AdvertiseAddress: "::",
+			},
+			expected: "",
+		},
 	}
 
 	for _, test := range tests {
@@ -104,7 +118,7 @@ func TestGetControllerManagerProbeAddress(t *testing.T) {
 			cfg: &kubeadmapi.ClusterConfiguration{
 				ControllerManager: kubeadmapi.ControlPlaneComponent{
 					ExtraArgs: map[string]string{
-						kubeControllerManagerAddressArg: "10.10.10.10",
+						kubeControllerManagerBindAddressArg: "10.10.10.10",
 					},
 				},
 			},
@@ -115,12 +129,34 @@ func TestGetControllerManagerProbeAddress(t *testing.T) {
 			cfg: &kubeadmapi.ClusterConfiguration{
 				ControllerManager: kubeadmapi.ControlPlaneComponent{
 					ExtraArgs: map[string]string{
-						kubeControllerManagerAddressArg: "2001:abcd:bcda::1",
+						kubeControllerManagerBindAddressArg: "2001:abcd:bcda::1",
 					},
 				},
 			},
 			expected: "2001:abcd:bcda::1",
 		},
+		{
+			desc: "setting controller manager extra address arg to 0.0.0.0 returns empty",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				ControllerManager: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeControllerManagerBindAddressArg: "0.0.0.0",
+					},
+				},
+			},
+			expected: "",
+		},
+		{
+			desc: "setting controller manager extra ipv6 address arg to :: returns empty",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				ControllerManager: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeControllerManagerBindAddressArg: "::",
+					},
+				},
+			},
+			expected: "",
+		},
 	}
 
 	for _, test := range tests {
@@ -133,6 +169,76 @@ func TestGetControllerManagerProbeAddress(t *testing.T) {
 	}
 }
 
+func TestGetSchedulerProbeAddress(t *testing.T) {
+	tests := []struct {
+		desc     string
+		cfg      *kubeadmapi.ClusterConfiguration
+		expected string
+	}{
+		{
+			desc: "no scheduler extra args leads to 127.0.0.1 being used",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Scheduler: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{},
+				},
+			},
+			expected: "127.0.0.1",
+		},
+		{
+			desc: "setting scheduler extra address arg to something acknowledges it",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Scheduler: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeSchedulerBindAddressArg: "10.10.10.10",
+					},
+				},
+			},
+			expected: "10.10.10.10",
+		},
+		{
+			desc: "setting scheduler extra ipv6 address arg to something acknowledges it",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Scheduler: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeSchedulerBindAddressArg: "2001:abcd:bcda::1",
+					},
+				},
+			},
+			expected: "2001:abcd:bcda::1",
+		},
+		{
+			desc: "setting scheduler extra ipv6 address arg to 0.0.0.0 returns empty",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Scheduler: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeSchedulerBindAddressArg: "0.0.0.0",
+					},
+				},
+			},
+			expected: "",
+		},
+		{
+			desc: "setting scheduler extra ipv6 address arg to :: returns empty",
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Scheduler: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{
+						kubeSchedulerBindAddressArg: "::",
+					},
+				},
+			},
+			expected: "",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.desc, func(t *testing.T) {
+			actual := GetSchedulerProbeAddress(test.cfg)
+			if actual != test.expected {
+				t.Errorf("Unexpected result from GetSchedulerProbeAddress:\n\texpected: %s\n\tactual: %s", test.expected, actual)
+			}
+		})
+	}
+}
 func TestGetEtcdProbeEndpoint(t *testing.T) {
 	var tests = []struct {
 		name             string