OCPEDGE-2276: Add support for platform None in TNA (Two-Node Arbiter) clusters

pkg/asset/machines/arbiter.go

@@ -31,6 +31,7 @@ import (
 	"github.com/openshift/installer/pkg/asset/rhcos"
 	"github.com/openshift/installer/pkg/types"
 	baremetaltypes "github.com/openshift/installer/pkg/types/baremetal"
+	nonetypes "github.com/openshift/installer/pkg/types/none"
 	ibmcloudapi "github.com/openshift/machine-api-provider-ibmcloud/pkg/apis"
 	ibmcloudprovider "github.com/openshift/machine-api-provider-ibmcloud/pkg/apis/ibmcloudprovider/v1"
 )
@@ -115,8 +116,8 @@ func (m *Arbiter) Generate(ctx context.Context, dependencies asset.Parents) erro
 	if ic.Arbiter == nil {
 		return nil
 	}
-	if ic.Platform.Name() != baremetaltypes.Name {
-		return fmt.Errorf("only BareMetal platform is supported for Arbiter deployments")
+	if ic.Platform.Name() != baremetaltypes.Name && ic.Platform.Name() != nonetypes.Name {
+		return fmt.Errorf("only BareMetal and None platforms are supported for Arbiter deployments")
 	}
 
 	pool := *ic.Arbiter
@@ -125,43 +126,47 @@ func (m *Arbiter) Generate(ctx context.Context, dependencies asset.Parents) erro
 	var ipClaims []ipamv1.IPAddressClaim
 	var ipAddrs []ipamv1.IPAddress
 
-	mpool := defaultBareMetalMachinePoolPlatform()
-	mpool.Set(ic.Platform.BareMetal.DefaultMachinePlatform)
-	mpool.Set(pool.Platform.BareMetal)
-	pool.Platform.BareMetal = &mpool
-
 	// Use managed user data secret, since we always have up to date images
 	// available in the cluster
 	arbiterUserDataSecretName := "arbiter-user-data-managed" // #nosec G101
-	enabledCaps := installConfig.Config.GetEnabledCapabilities()
-	if enabledCaps.Has(configv1.ClusterVersionCapabilityMachineAPI) {
-		machines, err = baremetal.Machines(clusterID.InfraID, ic, &pool, "arbiter", arbiterUserDataSecretName)
-		if err != nil {
-			return fmt.Errorf("failed to create arbiter machine objects: %w", err)
-		}
 
-		hostSettings, err := baremetal.ArbiterHosts(ic, machines, arbiterUserDataSecretName)
-		if err != nil {
-			return fmt.Errorf("failed to assemble host data: %w", err)
-		}
-
-		hosts, err := createHostAssetFiles(hostSettings.Hosts, arbiterHostFileName)
-		if err != nil {
-			return err
-		}
-		m.HostFiles = append(m.HostFiles, hosts...)
-
-		secrets, err := createSecretAssetFiles(hostSettings.Secrets, arbiterSecretFileName)
-		if err != nil {
-			return err
-		}
-		m.SecretFiles = append(m.SecretFiles, secrets...)
-
-		networkSecrets, err := createSecretAssetFiles(hostSettings.NetworkConfigSecrets, arbiterNetworkConfigSecretFileName)
-		if err != nil {
-			return err
+	// BareMetal-specific: configure machine pool and generate Machine API objects
+	if ic.Platform.BareMetal != nil {
+		mpool := defaultBareMetalMachinePoolPlatform()
+		mpool.Set(ic.Platform.BareMetal.DefaultMachinePlatform)
+		mpool.Set(pool.Platform.BareMetal)
+		pool.Platform.BareMetal = &mpool
+
+		enabledCaps := installConfig.Config.GetEnabledCapabilities()
+		if enabledCaps.Has(configv1.ClusterVersionCapabilityMachineAPI) {
+			machines, err = baremetal.Machines(clusterID.InfraID, ic, &pool, "arbiter", arbiterUserDataSecretName)
+			if err != nil {
+				return fmt.Errorf("failed to create arbiter machine objects: %w", err)
+			}
+
+			hostSettings, err := baremetal.ArbiterHosts(ic, machines, arbiterUserDataSecretName)
+			if err != nil {
+				return fmt.Errorf("failed to assemble host data: %w", err)
+			}
+
+			hosts, err := createHostAssetFiles(hostSettings.Hosts, arbiterHostFileName)
+			if err != nil {
+				return err
+			}
+			m.HostFiles = append(m.HostFiles, hosts...)
+
+			secrets, err := createSecretAssetFiles(hostSettings.Secrets, arbiterSecretFileName)
+			if err != nil {
+				return err
+			}
+			m.SecretFiles = append(m.SecretFiles, secrets...)
+
+			networkSecrets, err := createSecretAssetFiles(hostSettings.NetworkConfigSecrets, arbiterNetworkConfigSecretFileName)
+			if err != nil {
+				return err
+			}
+			m.NetworkConfigSecretFiles = append(m.NetworkConfigSecretFiles, networkSecrets...)
 		}
-		m.NetworkConfigSecretFiles = append(m.NetworkConfigSecretFiles, networkSecrets...)
 	}
 
 	data, err := UserDataSecret(arbiterUserDataSecretName, mign.File.Data)

pkg/asset/machines/arbiter_test.go

@@ -15,6 +15,7 @@ import (
 	"github.com/openshift/installer/pkg/types"
 	awstypes "github.com/openshift/installer/pkg/types/aws"
 	"github.com/openshift/installer/pkg/types/baremetal"
+	"github.com/openshift/installer/pkg/types/none"
 )
 
 func TestArbiterGenerateMachineConfigs(t *testing.T) {
@@ -219,7 +220,51 @@ func TestArbiterInstallOnlyForBaremetal(t *testing.T) {
 	arbiter := &Arbiter{}
 	err := arbiter.Generate(context.Background(), parents)
 	assert.NotNil(t, err, "expected arbiter generate to fail for non baremetal platforms")
-	assert.Contains(t, err.Error(), "only BareMetal platform is supported for Arbiter deployments")
+	assert.Contains(t, err.Error(), "only BareMetal and None platforms are supported for Arbiter deployments")
+}
+
+func TestArbiterInstallNonePlatform(t *testing.T) {
+	parents := asset.Parents{}
+	installConfig := installconfig.MakeAsset(
+		&types.InstallConfig{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-cluster",
+			},
+			SSHKey:     "ssh-rsa: dummy-key",
+			BaseDomain: "test-domain",
+			Platform: types.Platform{
+				None: &none.Platform{},
+			},
+			Arbiter: &types.MachinePool{
+				Hyperthreading: types.HyperthreadingDisabled,
+				Replicas:       ptr.To(int64(1)),
+			},
+		})
+
+	parents.Add(
+		&installconfig.ClusterID{
+			UUID:    "test-uuid",
+			InfraID: "test-infra-id",
+		},
+		installConfig,
+		rhcos.MakeAsset("test-image"),
+		(*rhcos.Release)(ptr.To("412.86.202208101040-0")),
+		&machine.Arbiter{
+			File: &asset.File{
+				Filename: "arbiter-ignition",
+				Data:     []byte("test-ignition"),
+			},
+		},
+	)
+	arbiter := &Arbiter{}
+	err := arbiter.Generate(context.Background(), parents)
+	assert.Nil(t, err, "expected arbiter generate to succeed for None platform")
+	// For None platform, no Machine API objects or BareMetalHost CRs should be generated
+	assert.Equal(t, 0, len(arbiter.MachineFiles), "expected no machine files for None platform")
+	assert.Equal(t, 0, len(arbiter.HostFiles), "expected no host files for None platform")
+	assert.Equal(t, 0, len(arbiter.SecretFiles), "expected no secret files for None platform")
+	// MachineConfigs should still be generated (hyperthreading disabled + SSH key)
+	assert.Greater(t, len(arbiter.MachineConfigFiles), 0, "expected machine config files for None platform")
 }
 
 func TestArbiterIsNotModified(t *testing.T) {

pkg/types/validation/installconfig.go

@@ -39,6 +39,7 @@ import (
 	gcpvalidation "github.com/openshift/installer/pkg/types/gcp/validation"
 	"github.com/openshift/installer/pkg/types/ibmcloud"
 	ibmcloudvalidation "github.com/openshift/installer/pkg/types/ibmcloud/validation"
+	"github.com/openshift/installer/pkg/types/none"
 	"github.com/openshift/installer/pkg/types/nutanix"
 	nutanixvalidation "github.com/openshift/installer/pkg/types/nutanix/validation"
 	"github.com/openshift/installer/pkg/types/openstack"
@@ -778,8 +779,8 @@ func validateControlPlane(installConfig *types.InstallConfig, fldPath *field.Pat
 
 func validateArbiter(platform *types.Platform, arbiterPool, masterPool *types.MachinePool, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
-	if platform != nil && platform.BareMetal == nil {
-		allErrs = append(allErrs, field.NotSupported(fldPath.Child("platform"), platform.Name(), []string{baremetal.Name}))
+	if platform != nil && platform.BareMetal == nil && platform.None == nil {
+		allErrs = append(allErrs, field.NotSupported(fldPath.Child("platform"), platform.Name(), []string{baremetal.Name, none.Name}))
 	}
 	if arbiterPool.Name != types.MachinePoolArbiterRoleName {
 		allErrs = append(allErrs, field.NotSupported(fldPath.Child("name"), arbiterPool.Name, []string{types.MachinePoolArbiterRoleName}))

pkg/types/validation/installconfig_test.go

@@ -3198,6 +3198,105 @@ func TestValidateTNF(t *testing.T) {
 	}
 }
 
+func TestValidateArbiter(t *testing.T) {
+	cases := []struct {
+		name     string
+		config   *types.InstallConfig
+		expected string
+	}{
+		{
+			config: installConfig().
+				PlatformNone().
+				MachinePoolArbiter(
+					machinePool().
+						Name("arbiter").
+						Hyperthreading(types.HyperthreadingEnabled).
+						Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(1).
+				CpReplicas(2).build(),
+			name:     "valid_platform_none",
+			expected: "",
+		},
+		{
+			config: installConfig().
+				PlatformBMWithHosts().
+				MachinePoolArbiter(
+					machinePool().
+						Name("arbiter").
+						Hyperthreading(types.HyperthreadingEnabled).
+						Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(1).
+				CpReplicas(2).build(),
+			name:     "valid_platform_baremetal",
+			expected: "",
+		},
+		{
+			config: installConfig().
+				PlatformAWS().
+				MachinePoolArbiter(machinePool().
+					Name("arbiter").
+					Hyperthreading(types.HyperthreadingEnabled).
+					Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(1).
+				CpReplicas(2).build(),
+			name:     "invalid_platform",
+			expected: `supported values: "baremetal", "none"`,
+		},
+		{
+			config: installConfig().
+				PlatformNone().
+				MachinePoolArbiter(machinePool().
+					Hyperthreading(types.HyperthreadingEnabled).
+					Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(1).
+				CpReplicas(2).build(),
+			name:     "invalid_arbiter_machine_pool_name",
+			expected: `arbiter.name: Unsupported value:`,
+		},
+		{
+			config: installConfig().
+				PlatformNone().
+				MachinePoolArbiter(machinePool().
+					Name("arbiter").
+					Hyperthreading(types.HyperthreadingEnabled).
+					Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(0).
+				CpReplicas(2).build(),
+			name:     "invalid_arbiter_machine_pool_size",
+			expected: `arbiter.replicas: Invalid value:`,
+		},
+		{
+			config: installConfig().
+				PlatformNone().
+				MachinePoolArbiter(machinePool().
+					Name("arbiter").
+					Hyperthreading(types.HyperthreadingEnabled).
+					Architecture(types.ArchitectureAMD64)).
+				MachinePoolCP(machinePool()).
+				ArbiterReplicas(1).
+				CpReplicas(1).build(),
+			name:     "invalid_master_machine_pool_size",
+			expected: `number of controlPlane replicas must be at least 2`,
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			err := validateArbiter(&tc.config.Platform, tc.config.Arbiter, tc.config.ControlPlane, field.NewPath("arbiter")).ToAggregate()
+
+			if tc.expected == "" {
+				assert.NoError(t, err)
+			} else {
+				assert.Regexp(t, tc.expected, err)
+			}
+		})
+	}
+}
+
 type credentialBuilder struct {
 	types.Credential
 }