mco: set KUBELET_NODE_IPS environment variable for kubelet

Author: tthvo

pkg/asset/machines/arbiter.go

@@ -202,7 +202,7 @@ func (m *Arbiter) Generate(ctx context.Context, dependencies asset.Parents) erro
 	// Reference: https://github.com/openshift/cluster-network-operator/blob/fc3e0e25b4cfa43e14122bdcdd6d7f2585017d75/pkg/network/cluster_config.go#L45-L52
 	if ic.Networking != nil && len(ic.Networking.ServiceNetwork) == 2 {
 		// Only configure kernel args for dual-stack clusters.
-		ignIPv6, err := machineconfig.ForDualStackAddresses("arbiter")
+		ignIPv6, err := machineconfig.ForDualStackAddresses("arbiter", ic)
 		if err != nil {
 			return fmt.Errorf("failed to create ignition to configure IPv6 for arbiter machines: %w", err)
 		}

pkg/asset/machines/machineconfig/ipv6.go

@@ -4,18 +4,42 @@ import (
 	"fmt"
 
 	igntypes "github.com/coreos/ignition/v2/config/v3_2/types"
+	"github.com/vincent-petithory/dataurl"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/utils/ptr"
 
 	mcfgv1 "github.com/openshift/api/machineconfiguration/v1"
 	"github.com/openshift/installer/pkg/asset/ignition"
+	"github.com/openshift/installer/pkg/types"
 )
 
 // ForDualStackAddresses creates the MachineConfig to tell kernel to configure the IP addresses with DHCP and DHCPV6.
-func ForDualStackAddresses(role string) (*mcfgv1.MachineConfig, error) {
+func ForDualStackAddresses(role string, ic *types.InstallConfig) (*mcfgv1.MachineConfig, error) {
+	kubeletAddr := "0.0.0.0"
+	if ic.InfraStack() == mcfgv1.IPFamiliesDualStackIPv6Primary {
+		kubeletAddr = "::"
+	}
+
 	ignConfig := igntypes.Config{
 		Ignition: igntypes.Ignition{
 			Version: igntypes.MaxVersion.String(),
 		},
+		Storage: igntypes.Storage{
+			Files: []igntypes.File{
+				{
+					Node: igntypes.Node{
+						Path:      "/etc/kubernetes/kubelet-workaround",
+						Overwrite: ptr.To(true),
+					},
+					FileEmbedded1: igntypes.FileEmbedded1{
+						Mode: ptr.To(644),
+						Contents: igntypes.Resource{
+							Source: ptr.To(dataurl.EncodeBytes([]byte(fmt.Sprintf("KUBELET_NODE_IPS=%s", kubeletAddr)))),
+						},
+					},
+				},
+			},
+		},
 	}
 
 	rawExt, err := ignition.ConvertToRawExtension(ignConfig)

pkg/asset/machines/master.go

@@ -608,7 +608,7 @@ func (m *Master) Generate(ctx context.Context, dependencies asset.Parents) error
 	// Reference: https://github.com/openshift/cluster-network-operator/blob/fc3e0e25b4cfa43e14122bdcdd6d7f2585017d75/pkg/network/cluster_config.go#L45-L52
 	if ic.Networking != nil && len(ic.Networking.ServiceNetwork) == 2 {
 		// Only configure kernel args for dual-stack clusters.
-		ignIPv6, err := machineconfig.ForDualStackAddresses("master")
+		ignIPv6, err := machineconfig.ForDualStackAddresses("master", ic)
 		if err != nil {
 			return errors.Wrap(err, "failed to create ignition to configure IPv6 for master machines")
 		}

pkg/asset/machines/worker.go

@@ -439,7 +439,7 @@ func (w *Worker) Generate(ctx context.Context, dependencies asset.Parents) error
 		// Reference: https://github.com/openshift/cluster-network-operator/blob/fc3e0e25b4cfa43e14122bdcdd6d7f2585017d75/pkg/network/cluster_config.go#L45-L52
 		if ic.Networking != nil && len(ic.Networking.ServiceNetwork) == 2 {
 			// Only configure kernel args for dual-stack clusters.
-			ignIPv6, err := machineconfig.ForDualStackAddresses("worker")
+			ignIPv6, err := machineconfig.ForDualStackAddresses("worker", ic)
 			if err != nil {
 				return errors.Wrap(err, "failed to create ignition to configure IPv6 for worker machines")
 			}