Merge pull request #7367 from shiftstack/configure-ipv6

Bug OCPBUGS-16249: Add ip=dhcp,dhcp6 option to Kernel args

pkg/asset/machines/machineconfig/ipv6.go

@@ -0,0 +1,42 @@
+package machineconfig
+
+import (
+	"fmt"
+
+	igntypes "github.com/coreos/ignition/v2/config/v3_2/types"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	"github.com/openshift/installer/pkg/asset/ignition"
+	mcfgv1 "github.com/openshift/machine-config-operator/pkg/apis/machineconfiguration.openshift.io/v1"
+)
+
+// ForDualStackAddresses creates the MachineConfig to tell kernel to configure the IP addresses with DHCP and DHCPV6.
+func ForDualStackAddresses(role string) (*mcfgv1.MachineConfig, error) {
+	ignConfig := igntypes.Config{
+		Ignition: igntypes.Ignition{
+			Version: igntypes.MaxVersion.String(),
+		},
+	}
+
+	rawExt, err := ignition.ConvertToRawExtension(ignConfig)
+	if err != nil {
+		return nil, err
+	}
+
+	return &mcfgv1.MachineConfig{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: mcfgv1.SchemeGroupVersion.String(),
+			Kind:       "MachineConfig",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name: fmt.Sprintf("99-dual-stack-%s", role),
+			Labels: map[string]string{
+				"machineconfiguration.openshift.io/role": role,
+			},
+		},
+		Spec: mcfgv1.MachineConfigSpec{
+			Config:          rawExt,
+			KernelArguments: []string{"ip=dhcp,dhcp6"},
+		},
+	}, nil
+}

pkg/asset/machines/master.go

@@ -542,6 +542,17 @@ func (m *Master) Generate(dependencies asset.Parents) error {
 		}
 		machineConfigs = append(machineConfigs, ignMultipath)
 	}
+	// The maximum number of networks supported on ServiceNetwork is two, one IPv4 and one IPv6 network.
+	// The cluster-network-operator handles the validation of this field.
+	// Reference: https://github.com/openshift/cluster-network-operator/blob/fc3e0e25b4cfa43e14122bdcdd6d7f2585017d75/pkg/network/cluster_config.go#L45-L52
+	if ic.Platform.Name() == openstacktypes.Name && len(installConfig.Config.ServiceNetwork) == 2 {
+		// Only configure kernel args for dual-stack clusters.
+		ignIPv6, err := machineconfig.ForDualStackAddresses("master")
+		if err != nil {
+			return errors.Wrap(err, "failed to create ignition to configure IPv6 for master machines")
+		}
+		machineConfigs = append(machineConfigs, ignIPv6)
+	}
 
 	m.MachineConfigFiles, err = machineconfig.Manifests(machineConfigs, "master", directory)
 	if err != nil {

pkg/asset/machines/worker.go

@@ -295,6 +295,17 @@ func (w *Worker) Generate(dependencies asset.Parents) error {
 			}
 			machineConfigs = append(machineConfigs, ignMultipath)
 		}
+		// The maximum number of networks supported on ServiceNetwork is two, one IPv4 and one IPv6 network.
+		// The cluster-network-operator handles the validation of this field.
+		// Reference: https://github.com/openshift/cluster-network-operator/blob/fc3e0e25b4cfa43e14122bdcdd6d7f2585017d75/pkg/network/cluster_config.go#L45-L52
+		if ic.Platform.Name() == openstacktypes.Name && len(installConfig.Config.ServiceNetwork) == 2 {
+			// Only configure kernel args for dual-stack clusters.
+			ignIPv6, err := machineconfig.ForDualStackAddresses("worker")
+			if err != nil {
+				return errors.Wrap(err, "failed to create ignition to configure IPv6 for worker machines")
+			}
+			machineConfigs = append(machineConfigs, ignIPv6)
+		}
 
 		switch ic.Platform.Name() {
 		case alibabacloudtypes.Name:

scripts/openstack/manifest-tests/dual-stack/install-config.yaml

@@ -0,0 +1,46 @@
+apiVersion: v1
+baseDomain: shiftstack.example.com
+featureSet: TechPreviewNoUpgrade
+controlPlane:
+  hyperthreading: Enabled
+  architecture: amd64
+  name: master
+  platform:
+    openstack:
+      type: ${COMPUTE_FLAVOR}
+  replicas: 3
+compute:
+- name: worker
+  platform:
+    openstack:
+      type: ${COMPUTE_FLAVOR}
+  replicas: 3
+metadata:
+  name: manifests1
+networking:
+  machineNetwork:
+  - cidr: "192.168.25.0/24"
+  - cidr: "fd2e:6f44:5dd8:c956::/64"
+  clusterNetwork:
+  - cidr: 10.128.0.0/14
+    hostPrefix: 23
+  - cidr: fd01::/48
+    hostPrefix: 64
+  serviceNetwork:
+  - 172.30.0.0/16
+  - fd02::/112
+platform:
+  openstack:
+    cloud: ${OS_CLOUD}
+    computeFlavor: ${COMPUTE_FLAVOR}  # deprecated in 4.7
+    ingressVIPs: ['192.168.25.79', 'fd2e:6f44:5dd8:c956:f816:3eff:fef1:1bad']
+    apiVIPs: ['192.168.25.199', 'fd2e:6f44:5dd8:c956:f816:3eff:fe78:cf36']
+    controlPlanePort:
+      fixedIPs:
+      - subnet:
+          name: external-subnet-v6
+      - subnet:
+          name: external-subnet
+      network:
+        name: external
+pullSecret: ${PULL_SECRET}

scripts/openstack/manifest-tests/dual-stack/test_machine-config.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import unittest
+import xmlrunner
+
+import os
+import sys
+import glob
+import yaml
+
+ASSETS_DIR = ""
+
+class GenerateMachineConfig(unittest.TestCase):
+    def setUp(self):
+        self.machine_configs = []
+        for machine_config_path in glob.glob(
+                f'{ASSETS_DIR}/openshift/99_openshift-machineconfig_99-dual-stack-*.yaml'
+        ):
+            with open(machine_config_path) as f:
+                self.machine_configs.append(yaml.load(f, Loader=yaml.FullLoader))
+
+    def test_kernel_args(self):
+        """Assert there are machine configs configuring the kernel args for masters and workers"""
+        for machine_config in self.machine_configs:
+            kernel_args = machine_config["spec"]["kernelArguments"]
+            self.assertIn("ip=dhcp,dhcp6", kernel_args)
+
+
+if __name__ == '__main__':
+    ASSETS_DIR = sys.argv.pop()
+    with open(os.environ.get('JUNIT_FILE', '/dev/null'), 'wb') as output:
+        unittest.main(testRunner=xmlrunner.XMLTestRunner(output=output), failfast=False, buffer=False, catchbreak=False, verbosity=2)