diff --git a/internal/csi-addons/rbd/volumegroup.go b/internal/csi-addons/rbd/volumegroup.go
index 9eb46daa9..1e5e19417 100644
--- a/internal/csi-addons/rbd/volumegroup.go
+++ b/internal/csi-addons/rbd/volumegroup.go
@@ -76,15 +76,26 @@ func (vs *VolumeGroupServer) RegisterService(server grpc.ServiceRegistrar) {
 //
 // Implementation steps:
 // 1. resolve all volumes given in the volume_ids list (can be empty)
-// 2. create the Volume Group
-// 3. add all volumes to the Volume Group
+// 2. check if the volumes belong to a (and all the same) group
+// 3. create the Volume Group
+// 4. verify that the Volume Group contains all the images (if it pre-exists)
+// 5. add all volumes to the Volume Group
 //
 // Idempotency should be handled by the rbd.Manager, keeping this function and
 // the potential error handling as simple as possible.
+//
+//nolint:gocyclo,cyclop // FIXME: make this function simpler
 func (vs *VolumeGroupServer) CreateVolumeGroup(
 	ctx context.Context,
 	req *volumegroup.CreateVolumeGroupRequest,
 ) (*volumegroup.CreateVolumeGroupResponse, error) {
+	var (
+		err       error
+		vgHandle  string
+		vg        types.VolumeGroup
+		groupName = req.GetName()
+	)
+
 	mgr := rbd.NewManager(vs.driverInstance, req.GetParameters(), req.GetSecrets())
 	defer mgr.Destroy(ctx)
 
@@ -102,62 +113,137 @@ func (vs *VolumeGroupServer) CreateVolumeGroup(
 				codes.InvalidArgument,
 				"failed to find required volume %q for volume group %q: %s",
 				id,
-				req.GetName(),
+				groupName,
 				err.Error())
 		}
 		volumes = append(volumes, vol)
-	}
 
-	log.DebugLog(ctx, "all %d Volumes for VolumeGroup %q have been found", len(volumes), req.GetName())
+		// only resolve vgHandle the 1st time
+		if i != 0 {
+			continue
+		}
 
-	// create a RBDVolumeGroup
-	vg, err := mgr.CreateVolumeGroup(ctx, req.GetName())
-	if err != nil {
-		return nil, status.Errorf(
-			codes.Internal,
-			"failed to create volume group %q: %s",
-			req.GetName(),
-			err.Error())
-	}
-
-	log.DebugLog(ctx, "VolumeGroup %q has been created: %+v", req.GetName(), vg)
-
-	// extract the flatten mode
-	flattenMode, err := getFlattenMode(ctx, req.GetParameters())
-	if err != nil {
-		return nil, err
-	}
-	// Flatten the image if the flatten mode is set to FlattenModeForce
-	// before adding it to the volume group.
-	for _, v := range volumes {
-		err = v.HandleParentImageExistence(ctx, flattenMode)
-		if err != nil {
-			err = fmt.Errorf("failed to handle parent image for volume group %q: %w", vg, err)
-
-			return nil, getGRPCError(err)
+		// reuse the existing group, it contains the volumes already
+		// check for pre-existing volume group name
+		vgHandle, err = vol.GetVolumeGroupID(ctx, mgr)
+		if err != nil && !errors.Is(err, rbderrors.ErrGroupNotFound) {
+			return nil, status.Errorf(
+				codes.Internal,
+				"could not get name of group for volume %q: %v",
+				volumes[0],
+				err)
 		}
 	}
-	// add each rbd-image to the RBDVolumeGroup
-	for _, vol := range volumes {
-		err = vg.AddVolume(ctx, vol)
+
+	log.DebugLog(ctx, "all %d Volumes for VolumeGroup %q have been found", len(volumes), groupName)
+
+	// verify that the volumes are not in a group yet
+	// if one volume is in a group, all other volumes need to be in the same group
+	if groupMatches, err := mgr.VolumesInSameGroup(ctx, volumes); !groupMatches || err != nil {
+		return nil, status.Errorf(
+			codes.Internal,
+			"not all volumes belong to the same group: %v",
+			err)
+	}
+
+	if vgHandle == "" {
+		// create a RBDVolumeGroup
+		vg, err = mgr.CreateVolumeGroup(ctx, groupName)
 		if err != nil {
 			return nil, status.Errorf(
 				codes.Internal,
-				"failed to add volume %q to volume group %q: %s",
-				vol,
-				req.GetName(),
+				"failed to create volume group %q: %s",
+				groupName,
 				err.Error())
 		}
+
+		log.DebugLog(ctx, "volume group %q has been created: %+v", groupName, vg)
+	} else {
+		vg, err = mgr.GetVolumeGroupByID(ctx, vgHandle)
+		if err != nil {
+			return nil, status.Errorf(
+				codes.Internal,
+				"failed to get volume group with id %q: %s",
+				vgHandle,
+				err.Error())
+		}
+
+		groupName, err = vg.GetName(ctx)
+		if err != nil {
+			return nil, status.Errorf(
+				codes.Internal,
+				"failed to get name of volume group %q: %s",
+				vg,
+				err.Error())
+		}
+
+		log.DebugLog(ctx, "existing volume group %q has been resolved: %+v", groupName, vg)
 	}
 
-	log.DebugLog(ctx, "all %d Volumes have been added to for VolumeGroup %q", len(volumes), req.GetName())
+	// TODO: check the number of volumes in the vg, it needs to be empty, or match len(volumes)
+	matches, err := mgr.CompareVolumesInGroup(ctx, volumes, vg)
+	if err != nil {
+		return nil, status.Errorf(
+			codes.Internal,
+			"failed to compare %d volumes with volume group %q: %s",
+			len(volumes),
+			groupName,
+			err.Error())
+	} else if !matches {
+		return nil, status.Errorf(
+			codes.Internal,
+			"volume group %q does not match with requested volumes",
+			groupName)
+	}
+
+	vols, err := vg.ListVolumes(ctx)
+	if err != nil {
+		return nil, status.Errorf(
+			codes.Internal,
+			"failed to list volumes of volume group %q: %s",
+			vg,
+			err.Error())
+	} else if len(vols) == 0 {
+		// need to add the volumes to the group
+
+		// extract the flatten mode
+		var flattenMode types.FlattenMode
+		flattenMode, err = getFlattenMode(ctx, req.GetParameters())
+		if err != nil {
+			return nil, err
+		}
+		// Flatten the image if the flatten mode is set to FlattenModeForce
+		// before adding it to the volume group.
+		for _, v := range volumes {
+			err = v.HandleParentImageExistence(ctx, flattenMode)
+			if err != nil {
+				err = fmt.Errorf("failed to handle parent image for volume group %q: %w", vg, err)
+
+				return nil, getGRPCError(err)
+			}
+		}
+		// add each rbd-image to the RBDVolumeGroup
+		for _, vol := range volumes {
+			err = vg.AddVolume(ctx, vol)
+			if err != nil {
+				return nil, status.Errorf(
+					codes.Internal,
+					"failed to add volume %q to volume group %q: %s",
+					vol,
+					groupName,
+					err.Error())
+			}
+		}
+
+		log.DebugLog(ctx, "all %d Volumes have been added to for volume group %q", len(volumes), vg)
+	}
 
 	csiVG, err := vg.ToCSI(ctx)
 	if err != nil {
 		return nil, status.Errorf(
 			codes.Internal,
 			"failed to convert volume group %q to CSI type: %s",
-			req.GetName(),
+			groupName,
 			err.Error())
 	}
 
diff --git a/internal/rbd/group_controllerserver.go b/internal/rbd/group_controllerserver.go
index 2dc171b00..0f28938cc 100644
--- a/internal/rbd/group_controllerserver.go
+++ b/internal/rbd/group_controllerserver.go
@@ -40,7 +40,7 @@ import (
 // group and its snapshot around, the group snapshot can be inspected to list
 // the snapshots of the images.
 //
-//nolint:gocyclo,cyclop // TODO: reduce complexity.
+//nolint:gocyclo,cyclop,gocognit // TODO: reduce complexity.
 func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 	ctx context.Context,
 	req *csi.CreateVolumeGroupSnapshotRequest,
@@ -53,6 +53,8 @@ func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 		// the VG and VGS should not have the same name
 		vgName  = req.GetName() + "-vg" // stable temporary name
 		vgsName = req.GetName()
+
+		vgNeedsDeletion = true
 	)
 
 	// Existence and conflict checks
@@ -70,7 +72,7 @@ func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 	volumes := make([]types.Volume, len(req.GetSourceVolumeIds()))
 	defer func() {
 		for _, volume := range volumes {
-			if vg != nil {
+			if vg != nil && vgNeedsDeletion {
 				// 'normal' cleanup, remove all images from the group
 				vgErr := vg.RemoveVolume(ctx, volume)
 				if vgErr != nil {
@@ -87,7 +89,7 @@ func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 			}
 		}
 
-		if vg != nil {
+		if vg != nil && vgNeedsDeletion {
 			// the VG should always be deleted, volumes can only belong to a single VG
 			log.DebugLog(ctx, "removing temporary volume group %q", vg)
 
@@ -116,6 +118,51 @@ func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 
 	log.DebugLog(ctx, "all %d Volumes for VolumeGroup %q have been found", len(volumes), vgsName)
 
+	// all volumes should belong to the same group, or to no group at all
+	groupMatches, err := mgr.VolumesInSameGroup(ctx, volumes)
+	if err != nil {
+		return nil, status.Errorf(
+			codes.Internal,
+			"failed to compare %d volumes: %s",
+			len(volumes),
+			err.Error())
+	} else if !groupMatches {
+		return nil, status.Error(
+			codes.Internal,
+			"not all volumes belong to the same group")
+	}
+
+	// check for pre-existing volume group name
+	vgHandle, err := volumes[0].GetVolumeGroupID(ctx, mgr)
+	if err != nil && !errors.Is(err, rbderrors.ErrGroupNotFound) {
+		return nil, status.Errorf(
+			codes.Internal,
+			"could not get volume group for volume %q: %v",
+			volumes[0],
+			err)
+	} else if vgHandle != "" {
+		vg, err = mgr.GetVolumeGroupByID(ctx, vgHandle)
+		// vg.Destroy(ctx) is called in a defer further up ^
+		if err != nil {
+			return nil, status.Errorf(
+				codes.InvalidArgument,
+				"failed to resolve volume group with id %q: %s",
+				vgHandle,
+				err.Error())
+		}
+
+		vgName, err = vg.GetName(ctx)
+		if err != nil {
+			return nil, status.Errorf(
+				codes.InvalidArgument,
+				"failed to get name of volume group %q: %s",
+				vg,
+				err.Error())
+		}
+
+		vgNeedsDeletion = false
+	}
+
 	groupSnapshot, err = mgr.GetVolumeGroupSnapshotByName(ctx, vgsName)
 	if groupSnapshot != nil {
 		defer groupSnapshot.Destroy(ctx)
@@ -155,24 +202,35 @@ func (cs *ControllerServer) CreateVolumeGroupSnapshot(
 			errList)
 	}
 
-	// create a temporary VolumeGroup with a different name
-	vg, err = mgr.CreateVolumeGroup(ctx, vgName)
+	if vg == nil {
+		// create a temporary VolumeGroup with a different name
+		vg, err = mgr.CreateVolumeGroup(ctx, vgName)
+		if err != nil {
+			return nil, status.Errorf(
+				codes.Internal,
+				"failed to create volume group %q: %s",
+				vgName,
+				err.Error())
+		}
+		// vg.Destroy(ctx) is called in a defer further up ^
+
+		log.DebugLog(ctx, "VolumeGroup %q has been created: %+v", vgName, vg)
+	}
+
+	vols, err := vg.ListVolumes(ctx)
 	if err != nil {
 		return nil, status.Errorf(
 			codes.Internal,
-			"failed to create volume group %q: %s",
-			vgName,
+			"failed to list volumes of volume group %q: %s",
+			vg,
 			err.Error())
-	}
-	// vg.Destroy(ctx) is called in a defer further up ^
-
-	log.DebugLog(ctx, "VolumeGroup %q has been created: %+v", vgName, vg)
-
-	// add images to the group
-	for _, volume := range volumes {
-		err = vg.AddVolume(ctx, volume)
-		if err != nil {
-			return nil, status.Error(codes.Aborted, err.Error())
+	} else if len(vols) == 0 {
+		// add images to the group
+		for _, volume := range volumes {
+			err = vg.AddVolume(ctx, volume)
+			if err != nil {
+				return nil, status.Error(codes.Aborted, err.Error())
+			}
 		}
 	}