diff --git a/nvflare/private/fed/client/client_engine.py b/nvflare/private/fed/client/client_engine.py
index 4e248233c6..6e8d536409 100644
--- a/nvflare/private/fed/client/client_engine.py
+++ b/nvflare/private/fed/client/client_engine.py
@@ -66,7 +66,6 @@ def __init__(self, client: FederatedClient, args, rank, workers=5):
             rank: local process rank
             workers: number of workers
         """
-        super().__init__()
         MessagingEngine.__init__(self, messenger=self)
         self.client = client
         self.client_name = client.client_name
diff --git a/nvflare/private/fed/client/client_run_manager.py b/nvflare/private/fed/client/client_run_manager.py
index bf83f98ef9..2c1234562b 100644
--- a/nvflare/private/fed/client/client_run_manager.py
+++ b/nvflare/private/fed/client/client_run_manager.py
@@ -81,7 +81,6 @@ def __init__(
             handlers: available handlers.
             conf: ClientJsonConfigurator object
         """
-        super().__init__()
         MessagingEngine.__init__(self, messenger=self)
         self.client = client
         self.handlers = handlers
diff --git a/nvflare/private/fed/server/run_manager.py b/nvflare/private/fed/server/run_manager.py
index 2691fe494a..14002ef02a 100644
--- a/nvflare/private/fed/server/run_manager.py
+++ b/nvflare/private/fed/server/run_manager.py
@@ -59,11 +59,7 @@ def __init__(
         self.client_manager = client_manager
         self.handlers = handlers
         self.aux_runner = AuxRunner(self)
-        self.object_streamer = ObjectStreamer(self.aux_runner)
-        self.reliable_messenger = ReliableMessenger(self.aux_runner)
         self.add_handler(self.aux_runner)
-        self.add_handler(self.object_streamer)
-        self.add_handler(self.reliable_messenger)
 
         if job_id:
             job_ctx_props = self.create_job_processing_context_properties(workspace, job_id)
diff --git a/nvflare/private/msg_engine.py b/nvflare/private/msg_engine.py
index 5c3ef74063..6bc5905094 100644
--- a/nvflare/private/msg_engine.py
+++ b/nvflare/private/msg_engine.py
@@ -11,6 +11,7 @@
 # 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.
+import threading
 from typing import List
 
 from nvflare.apis.aux_spec import AuxMessenger
@@ -18,18 +19,40 @@
 from nvflare.apis.rm import RMEngine
 from nvflare.apis.shareable import Shareable
 from nvflare.apis.streaming import ConsumerFactory, ObjectProducer, StreamableEngine, StreamContext
+from nvflare.apis.fl_component import FLComponent
 
 from .rm_runner import ReliableMessenger
 from .stream_runner import ObjectStreamer
 
 
-class MessagingEngine(StreamableEngine, RMEngine):
+class MessagingEngine(StreamableEngine, RMEngine, FLComponent):
     def __init__(self, messenger: AuxMessenger):
+        FLComponent.__init__(self)
         self.messenger = messenger
-        self.streamer = ObjectStreamer(messenger)
-        self.reliable_messenger = ReliableMessenger(messenger)
+        self._lock = threading.Lock()
+
+        # We do not immediately create ObjectStreamer and ReliableMessenger here since they need to
+        # register aux CBs with the AuxMessenger, but the AuxMessenger may not be ready now.
+        # Instead, we will create them later when needed.
+        self.streamer = None
+        self.reliable_messenger = None
+
+    def _open_streamer(self):
+        with self._lock:
+            if not self.streamer:
+                self.streamer = ObjectStreamer(self.messenger)
+
+    def _open_reliable_messenger(self):
+        self.logger.info(f"trying to open reliable messenger for {id(self)}")
+        with self._lock:
+            if not self.reliable_messenger:
+                self.reliable_messenger = ReliableMessenger(self.messenger)
+                self.logger.info(f"reliable_messenger is opened for engine {id(self)}, aux {id(self.messenger)}")
+            else:
+                self.logger.info(f"reliable messenger for {id(self)} is already opened")
 
     def register_reliable_request_handler(self, channel: str, topic: str, handler_f, **handler_kwargs):
+        self._open_reliable_messenger()
         self.reliable_messenger.register_request_handler(channel, topic, handler_f, **handler_kwargs)
 
     def send_reliable_request(
@@ -44,12 +67,15 @@ def send_reliable_request(
         optional=False,
         secure=False,
     ) -> Shareable:
+        self._open_reliable_messenger()
         return self.reliable_messenger.send_request(
             target, channel, topic, request, per_msg_timeout, tx_timeout, fl_ctx, secure, optional
         )
 
     def shutdown_reliable_messenger(self):
-        self.reliable_messenger.shutdown()
+        with self._lock:
+            if self.reliable_messenger:
+                self.reliable_messenger.shutdown()
 
     def register_stream_processing(
         self,
@@ -59,6 +85,7 @@ def register_stream_processing(
         stream_done_cb=None,
         **cb_kwargs,
     ):
+        self._open_streamer()
         return self.streamer.register_stream_processing(channel, topic, factory, stream_done_cb, **cb_kwargs)
 
     def stream_objects(
@@ -72,6 +99,7 @@ def stream_objects(
         optional=False,
         secure=False,
     ):
+        self._open_streamer()
         return self.streamer.stream(
             channel,
             topic,
@@ -84,7 +112,9 @@ def stream_objects(
         )
 
     def shutdown_streamer(self):
-        self.streamer.shutdown()
+        with self._lock:
+            if self.streamer:
+                self.streamer.shutdown()
 
     def shutdown_messaging(self):
         self.shutdown_streamer()