Normal connection -> Communication ends after about 1 hour!! Anyone who knows the exception information below

[zeroche72]

I succeeded in connecting Siemens CPU through OPC-UA communication.
(Attach the code below)
However, after a certain period of time, it is terminated after an exception occurs as shown below.
Anyone who knows why please help me

########################### My Code
from opcua import Client
import logging
import time
from datetime import datetime

url = "opc.tcp://10.27.176.101:4840"

client = Client(url)
client.set_user("OpcUaClient")
client.set_password("12345678")
client.connect()

while True:
____try:
________ rst = client.get_node("ns=2;s=/Channel/Spindle/driveLoad[1]")
________ print(rst.get_value())
________print('#==================#')
________time.sleep(0.05)
____except(TimeoutError):
________print('-------------------------------------timeout')
________ print(str(TimeoutError)
________continue

############################### exception information
ERROR:opcua.client.ua_client.Socket:Protocol Error
Traceback (most recent call last):
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 101, in _run
self._receive()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 112, in _receive
msg = self._connection.receive_from_socket(self._socket)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 363, in receive_from_socket
return self.receive_from_header_and_body(header, ua.utils.Buffer(body))
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 328, in receive_from_header_and_body
self._check_sym_header(security_header)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 276, in _check_sym_header
self.next_security_token.TokenId))
opcua.ua.uaerrors._base.UaError: Invalid security token id 6, expected 5 or 0
ERROR:opcua.client.ua_client.Socket:Protocol Error
Traceback (most recent call last):
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 101, in _run
self._receive()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 112, in _receive
msg = self._connection.receive_from_socket(self._socket)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 363, in receive_from_socket
return self.receive_from_header_and_body(header, ua.utils.Buffer(body))
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 335, in receive_from_header_and_body
return self._receive(chunk)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 366, in _receive
self._check_incoming_chunk(msg)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 311, in _check_incoming_chunk
.format(self._peer_sequence_number, num))
opcua.ua.uaerrors._base.UaError: Wrong sequence 3061 -> 3063 (server bug or replay attack)
Traceback (most recent call last):
File "test.py", line 45, in
Exception in thread Thread-2:
Traceback (most recent call last):
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\threading.py", line 916, in _bootstrap_inner
self.run()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\client.py", line 68, in run
val = server_state.get_value()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 153, in get_value
result = self.get_data_value()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 162, in get_data_value
return self.get_attribute(ua.AttributeIds.Value)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 273, in get_attribute
result = self.server.read(params)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 337, in read
data = self._uasocket.send_request(request)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 83, in send_request
data = future.result(self.timeout)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\concurrent\futures_base.py", line 434, in result
raise TimeoutError()
concurrent.futures._base.TimeoutError
logWrite(str(rst.get_value()))

File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 153, in get_value
result = self.get_data_value()
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 162, in get_data_value
return self.get_attribute(ua.AttributeIds.Value)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 273, in get_attribute
result = self.server.read(params)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 337, in read
data = self._uasocket.send_request(request)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 83, in send_request
data = future.result(self.timeout)
File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\concurrent\futures_base.py", line 434, in result
raise TimeoutError()
concurrent.futures._base.TimeoutError

[schroeder-]

This library is not supported anymore (#1475). Try to migrate to asyncua and if the bug still exists we will look into it in asyncua.