I am experiencing an intermittent OPC UA server issue on CODESYS Control for Raspberry Pi SL 4.21.0.0.
Runtime information:
codesyscontrol 4.21.0.0
Raspberry Pi 4 Model B Rev 1.1 - 4Gb
OPC UA Server: CmpOPCUAServer 3.5.22.x
Server IP: 192.168.0.110
OPC UA endpoint: opc.tcp://192.168.0.110:4840
The main OPC UA client is Node-RED running on 192.168.0.111. This has an active subscription with some tags and also some write functions active.
The system normally works correctly for a period, but at some time the OPC UA communication stopped.
Node-RED started reconnecting continuously but could not reconnect.
I also tried connecting using UaExpert, but UaExpert returned: BadTimeout
At the same time, the PLC application itself was still running.
Before restarting CODESYS, I captured the TCP connections.
The OPC UA server was still listening:
tcp 11 0 192.168.0.110:4840 0.0.0.0:* LISTEN
However, there were many connections from the Node-RED client stuck in CLOSE_WAIT:
192.168.0.110:4840 192.168.0.111:45008 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:53678 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:44032 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:36612 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:45012 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:36592 CLOSE_WAIT
...
Some of these sockets also had data remaining in Recv-Q, for example:
Recv-Q = 61
Recv-Q = 121
There were roughly 15–20 OPC UA connections in CLOSE_WAIT.
Restarting only the CODESYS runtime immediately restored OPC UA communication.
After restart:
LISTEN 0 10 192.168.0.110:4840
and both Node-RED and UaExpert can connect normally again. There are no obvious OPC UA errors during startup or in log.
On RPI 2 I had a memory leak regarding OPCUA so I had to upgrade to RPI4.
What can I do in this case?
Thank you!
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I updated the runtime to CODESYS Control for Raspberry Pi SL 4.22.0.0, SDK 3.5.22.30.
Same outcome as before. Now I study if migrating to PFC100 is ok or to change to Siemens PLC because of this issue.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I updated the runtime to CODESYS Control for Raspberry Pi SL 4.22.0.0, SDK 3.5.22.30.
Same outcome as before. Now I study if migrating to PFC100 is ok or to change to Siemens PLC because of this issue.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Hello,
I am experiencing an intermittent OPC UA server issue on CODESYS Control for Raspberry Pi SL 4.21.0.0.
Runtime information:
codesyscontrol 4.21.0.0
Raspberry Pi 4 Model B Rev 1.1 - 4Gb
OPC UA Server: CmpOPCUAServer 3.5.22.x
Server IP: 192.168.0.110
OPC UA endpoint: opc.tcp://192.168.0.110:4840
The main OPC UA client is Node-RED running on 192.168.0.111. This has an active subscription with some tags and also some write functions active.
The system normally works correctly for a period, but at some time the OPC UA communication stopped.
Node-RED started reconnecting continuously but could not reconnect.
I also tried connecting using UaExpert, but UaExpert returned: BadTimeout
At the same time, the PLC application itself was still running.
Before restarting CODESYS, I captured the TCP connections.
The OPC UA server was still listening:
tcp 11 0 192.168.0.110:4840 0.0.0.0:* LISTEN
However, there were many connections from the Node-RED client stuck in CLOSE_WAIT:
192.168.0.110:4840 192.168.0.111:45008 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:53678 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:44032 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:36612 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:45012 CLOSE_WAIT
192.168.0.110:4840 192.168.0.111:36592 CLOSE_WAIT
...
Some of these sockets also had data remaining in Recv-Q, for example:
Recv-Q = 61
Recv-Q = 121
There were roughly 15–20 OPC UA connections in CLOSE_WAIT.
Restarting only the CODESYS runtime immediately restored OPC UA communication.
After restart:
LISTEN 0 10 192.168.0.110:4840
and both Node-RED and UaExpert can connect normally again. There are no obvious OPC UA errors during startup or in log.
On RPI 2 I had a memory leak regarding OPCUA so I had to upgrade to RPI4.
What can I do in this case?
Thank you!
I updated the runtime to CODESYS Control for Raspberry Pi SL 4.22.0.0, SDK 3.5.22.30.
Same outcome as before. Now I study if migrating to PFC100 is ok or to change to Siemens PLC because of this issue.
I updated the runtime to CODESYS Control for Raspberry Pi SL 4.22.0.0, SDK 3.5.22.30.
Same outcome as before. Now I study if migrating to PFC100 is ok or to change to Siemens PLC because of this issue.