diff --git a/weed/topology/rack.go b/weed/topology/rack.go
index f526cd84d..246e8f190 100644
--- a/weed/topology/rack.go
+++ b/weed/topology/rack.go
@@ -1,10 +1,12 @@
 package topology
 
 import (
+	"net"
 	"slices"
 	"strings"
 	"time"
 
+	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
 	"github.com/seaweedfs/seaweedfs/weed/storage/types"
 	"github.com/seaweedfs/seaweedfs/weed/util"
@@ -34,17 +36,66 @@ func (r *Rack) FindDataNode(ip string, port int) *DataNode {
 	}
 	return nil
 }
-func (r *Rack) GetOrCreateDataNode(ip string, port int, grpcPort int, publicUrl string, maxVolumeCounts map[string]uint32) *DataNode {
+
+// FindDataNodeById finds a DataNode by its ID using O(1) map lookup
+func (r *Rack) FindDataNodeById(id string) *DataNode {
+	r.RLock()
+	defer r.RUnlock()
+	if c, ok := r.children[NodeId(id)]; ok {
+		return c.(*DataNode)
+	}
+	return nil
+}
+
+func (r *Rack) GetOrCreateDataNode(ip string, port int, grpcPort int, publicUrl string, id string, maxVolumeCounts map[string]uint32) *DataNode {
 	r.Lock()
 	defer r.Unlock()
-	for _, c := range r.children {
+
+	// Determine the node ID: use provided id, or fall back to ip:port for backward compatibility
+	nodeId := id
+	if nodeId == "" {
+		nodeId = util.JoinHostPort(ip, port)
+	}
+
+	// First, try to find by node ID using O(1) map lookup (stable identity)
+	if c, ok := r.children[NodeId(nodeId)]; ok {
 		dn := c.(*DataNode)
-		if dn.MatchLocation(ip, port) {
-			dn.LastSeen = time.Now().Unix()
-			return dn
+		// Update the IP/Port in case they changed (e.g., pod rescheduled in K8s)
+		dn.Ip = ip
+		dn.Port = port
+		dn.GrpcPort = grpcPort
+		dn.PublicUrl = publicUrl
+		dn.LastSeen = time.Now().Unix()
+		return dn
+	}
+
+	// For backward compatibility: if id was provided, also check by ip:port
+	// to handle transition from old (ip:port) to new (explicit id) behavior
+	if id != "" {
+		for oldId, c := range r.children {
+			dn := c.(*DataNode)
+			if dn.MatchLocation(ip, port) {
+				// Only transition if the oldId is in ip:port format (legacy identification).
+				// If oldId is an explicit id (not ip:port format), this is a different node
+				// that happens to reuse the same ip:port - don't incorrectly merge them.
+				if _, _, err := net.SplitHostPort(string(oldId)); err != nil {
+					// oldId is not in ip:port format, so it's an explicit id from another node
+					glog.Warningf("Volume server with id %s has ip:port %s:%d which is used by node %s", id, ip, port, oldId)
+					continue
+				}
+				// Found a node by ip:port, transition it to use the new explicit id
+				glog.V(0).Infof("Volume server %s transitioning id from %s to %s", dn.Url(), oldId, id)
+				// Re-key the node in the children map with the new id
+				delete(r.children, oldId)
+				dn.id = NodeId(id)
+				r.children[NodeId(id)] = dn
+				dn.LastSeen = time.Now().Unix()
+				return dn
+			}
 		}
 	}
-	dn := NewDataNode(util.JoinHostPort(ip, port))
+
+	dn := NewDataNode(nodeId)
 	dn.Ip = ip
 	dn.Port = port
 	dn.GrpcPort = grpcPort
diff --git a/weed/topology/topology_test.go b/weed/topology/topology_test.go
index 8515d2f81..02bf12e07 100644
--- a/weed/topology/topology_test.go
+++ b/weed/topology/topology_test.go
@@ -34,7 +34,7 @@ func TestHandlingVolumeServerHeartbeat(t *testing.T) {
 	maxVolumeCounts := make(map[string]uint32)
 	maxVolumeCounts[""] = 25
 	maxVolumeCounts["ssd"] = 12
-	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", maxVolumeCounts)
+	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", "", maxVolumeCounts)
 
 	{
 		volumeCount := 7
@@ -180,7 +180,7 @@ func TestAddRemoveVolume(t *testing.T) {
 	maxVolumeCounts := make(map[string]uint32)
 	maxVolumeCounts[""] = 25
 	maxVolumeCounts["ssd"] = 12
-	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", maxVolumeCounts)
+	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", "", maxVolumeCounts)
 
 	v := storage.VolumeInfo{
 		Id:               needle.VolumeId(1),
@@ -218,7 +218,7 @@ func TestVolumeReadOnlyStatusChange(t *testing.T) {
 	rack := dc.GetOrCreateRack("rack1")
 	maxVolumeCounts := make(map[string]uint32)
 	maxVolumeCounts[""] = 25
-	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", maxVolumeCounts)
+	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", "", maxVolumeCounts)
 
 	// Create a writable volume
 	v := storage.VolumeInfo{
@@ -267,7 +267,7 @@ func TestVolumeReadOnlyAndRemoteStatusChange(t *testing.T) {
 	rack := dc.GetOrCreateRack("rack1")
 	maxVolumeCounts := make(map[string]uint32)
 	maxVolumeCounts[""] = 25
-	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", maxVolumeCounts)
+	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", "", maxVolumeCounts)
 
 	// Create a writable, local volume
 	v := storage.VolumeInfo{
@@ -331,7 +331,7 @@ func TestListCollections(t *testing.T) {
 	topo := NewTopology("weedfs", sequence.NewMemorySequencer(), 32*1024, 5, false)
 	dc := topo.GetOrCreateDataCenter("dc1")
 	rack := dc.GetOrCreateRack("rack1")
-	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", nil)
+	dn := rack.GetOrCreateDataNode("127.0.0.1", 34534, 0, "127.0.0.1", "", nil)
 
 	topo.RegisterVolumeLayout(storage.VolumeInfo{
 		Id:               needle.VolumeId(1111),