feat(network): bind live migration to a dedicated SystemNetwork

images/virtualization-artifact/cmd/virtualization-controller/main.go

@@ -46,6 +46,7 @@ import (
 	"github.com/deckhouse/virtualization-controller/pkg/controller/evacuation"
 	"github.com/deckhouse/virtualization-controller/pkg/controller/indexer"
 	"github.com/deckhouse/virtualization-controller/pkg/controller/livemigration"
+	"github.com/deckhouse/virtualization-controller/pkg/controller/migrationiface"
 	mc "github.com/deckhouse/virtualization-controller/pkg/controller/moduleconfig"
 	mcapi "github.com/deckhouse/virtualization-controller/pkg/controller/moduleconfig/api"
 	"github.com/deckhouse/virtualization-controller/pkg/controller/nodeusbdevice"
@@ -96,6 +97,8 @@ const (
 
 	SdnEnabledEnv  = "SDN_ENABLED"
 	clusterUUIDEnv = "CLUSTER_UUID"
+
+	migrationSystemNetworkNameEnv = "MIGRATION_SYSTEM_NETWORK_NAME"
 )
 
 func main() {
@@ -390,6 +393,12 @@ func main() {
 		os.Exit(1)
 	}
 
+	migrationIfaceLogger := logger.NewControllerLogger(migrationiface.ControllerName, logLevel, logOutput, logDebugVerbosity, logDebugControllerList)
+	if _, err = migrationiface.NewController(ctx, mgr, migrationIfaceLogger, os.Getenv(migrationSystemNetworkNameEnv)); err != nil {
+		log.Error(err.Error())
+		os.Exit(1)
+	}
+
 	resourceSliceLogger := logger.NewControllerLogger(resourceslice.ControllerName, logLevel, logOutput, logDebugVerbosity, logDebugControllerList)
 	if _, err = resourceslice.NewController(ctx, mgr, resourceSliceLogger); err != nil {
 		log.Error(err.Error())

images/virtualization-artifact/pkg/common/annotations/annotations.go

@@ -193,6 +193,12 @@ const (
 	// AnnNetworksStatus is the annotation for view current network configuration into Pod.
 	AnnNetworksStatus = "network.deckhouse.io/networks-status"
 
+	// AnnMigrationIface names the kernel interface that virt-handler binds
+	// live-migration traffic to. Written on Nodes by the migrationiface
+	// controller from a SystemNetwork CR (sdn module); read by virt-handler
+	// on startup.
+	AnnMigrationIface = AnnAPIGroupV + "/migration-iface"
+
 	// AnnVirtualDiskOriginalAnnotations is the annotation for storing original VirtualDisk annotations.
 	AnnVirtualDiskOriginalAnnotations = AnnAPIGroupV + "/vd-original-annotations"
 	// AnnVirtualDiskOriginalLabels is the annotation for storing original VirtualDisk labels.

images/virtualization-artifact/pkg/controller/indexer/indexer.go

@@ -76,6 +76,9 @@ const (
 
 	IndexFieldResourceSliceByPoolName = "spec.pool.name"
 	IndexFieldResourceSliceByDriver   = "spec.driver"
+
+	IndexFieldSNNNIAByNodeName          = "snnnia.status.nodeName"
+	IndexFieldSNNNIABySystemNetworkName = "snnnia.spec.systemNetworkName"
 )
 
 var IndexGetters = []IndexGetter{
@@ -114,6 +117,11 @@ var IndexGettersUSB = []IndexGetter{
 	IndexResourceSliceByDriver,
 }
 
+var IndexGettersSDN = []IndexGetter{
+	IndexSNNNIAByNodeName,
+	IndexSNNNIABySystemNetworkName,
+}
+
 type IndexGetter func() (obj client.Object, field string, extractValue client.IndexerFunc)
 
 func IndexALL(ctx context.Context, mgr manager.Manager) error {
@@ -126,6 +134,15 @@ func IndexALL(ctx context.Context, mgr manager.Manager) error {
 		}
 	}
 
+	if featuregates.Default().Enabled(featuregates.SDN) {
+		for _, fn := range IndexGettersSDN {
+			obj, field, indexFunc := fn()
+			if err := mgr.GetFieldIndexer().IndexField(ctx, obj, field, indexFunc); err != nil {
+				return err
+			}
+		}
+	}
+
 	for _, fn := range IndexGetters {
 		obj, field, indexFunc := fn()
 		if err := mgr.GetFieldIndexer().IndexField(ctx, obj, field, indexFunc); err != nil {

images/virtualization-artifact/pkg/controller/indexer/snnnia_indexer.go

@@ -0,0 +1,57 @@
+/*
+Copyright 2026 Flant JSC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package indexer
+
+import (
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var snnniaGVK = schema.GroupVersionKind{
+	Group:   "network.deckhouse.io",
+	Version: "v1alpha1",
+	Kind:    "SystemNetworkNodeNetworkInterfaceAttachment",
+}
+
+func snnniaSeed() client.Object {
+	u := &unstructured.Unstructured{}
+	u.SetGroupVersionKind(snnniaGVK)
+	return u
+}
+
+func snnniaIndexer(path ...string) client.IndexerFunc {
+	return func(o client.Object) []string {
+		u, ok := o.(*unstructured.Unstructured)
+		if !ok || u == nil {
+			return nil
+		}
+		v, _, _ := unstructured.NestedString(u.Object, path...)
+		if v == "" {
+			return nil
+		}
+		return []string{v}
+	}
+}
+
+func IndexSNNNIAByNodeName() (client.Object, string, client.IndexerFunc) {
+	return snnniaSeed(), IndexFieldSNNNIAByNodeName, snnniaIndexer("status", "nodeName")
+}
+
+func IndexSNNNIABySystemNetworkName() (client.Object, string, client.IndexerFunc) {
+	return snnniaSeed(), IndexFieldSNNNIABySystemNetworkName, snnniaIndexer("spec", "systemNetworkName")
+}

images/virtualization-artifact/pkg/controller/migrationiface/migrationiface_controller.go

@@ -0,0 +1,72 @@
+/*
+Copyright 2026 Flant JSC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package migrationiface annotates each Node with the kernel interface name
+// of a dedicated live-migration network, resolved from sdn's
+// SystemNetworkNodeNetworkInterfaceAttachment + NodeNetworkInterface.
+// virt-handler reads the annotation (see pkg/common/annotations.AnnMigrationIface)
+// at startup to bind migration traffic to that interface.
+package migrationiface
+
+import (
+	"context"
+	"time"
+
+	"k8s.io/utils/ptr"
+	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+
+	"github.com/deckhouse/deckhouse/pkg/log"
+	"github.com/deckhouse/virtualization-controller/pkg/featuregates"
+	"github.com/deckhouse/virtualization-controller/pkg/logger"
+)
+
+const ControllerName = "migrationiface-controller"
+
+func NewController(
+	ctx context.Context,
+	mgr manager.Manager,
+	log *log.Logger,
+	systemNetworkName string,
+) (controller.Controller, error) {
+	if !featuregates.Default().Enabled(featuregates.SDN) {
+		log.Info("SDN feature gate is disabled, migrationiface controller is disabled")
+		return nil, nil
+	}
+	if systemNetworkName == "" {
+		log.Info("MIGRATION_SYSTEM_NETWORK_NAME is empty, migrationiface controller is disabled")
+		return nil, nil
+	}
+
+	r := NewReconciler(mgr.GetClient(), systemNetworkName, log)
+
+	c, err := controller.New(ControllerName, mgr, controller.Options{
+		Reconciler:       r,
+		RecoverPanic:     ptr.To(true),
+		LogConstructor:   logger.NewConstructor(log),
+		CacheSyncTimeout: 10 * time.Minute,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if err = r.SetupController(ctx, mgr, c); err != nil {
+		return nil, err
+	}
+
+	log.Info("Initialized migrationiface controller", "systemNetwork", systemNetworkName)
+	return c, nil
+}