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Equivalent CXA_Lib for RIL_OpcUaServer

Equivalent CXA_Lib for RIL_OpcUaServer

Established Member


is there an exisiting PLC Lib in CXA for the former IW Lib RIL_OpcUaServer?


If not, is something like this planned?

Thanks in advanced!


Community Moderator
Community Moderator

Hi maurusbien,

you could just use the CXA_Datalayer and read some node from the OPCUA Server from the datalayer.

Eg. num-sessions.

If the node does't exist you should get some error, so the server doesn't exist.



from priciple point of view you are absolutely right. But checking if OPC UA Nodes are available is not sufficent enough in the customers use case. Like did with the former RIL_OpcUaServer Library, it is necessary to know in which state the OPC UA Server is and if it is ready fpr communication:

Are the green marked information about the OPC UA Server available somehow via the Data Layer?


Established Member

Hi maurusbien,

unfortunately this information is not available over datalayer in version 1.10. But it will available in Version 1.12. The implementation is already done. The information which is available will be similar to ServerStatus, which is already available over OPC UA. Probably it is workaround, the the customer can use the information over OPC UA. See also screenshot below.

Best regards,




Established Member

Hello Sebastian,

thanks for the detailed answer. I will forward this information and afterwards accept your solution or post a re-question. But for me everything is clear so far.

Best regards,



I tried from plc side to acces the datalayer node for opc ua serverstatus with DL_ReadNode. But I get an accesserror. It seems that the node on the datalayer has as dataye a enum with basetype string? This is not allowed on plc side. 

There are any other way to get frequently the state of the opc ua server in the plc?

Thanks in advance, Matthias

Hello Matthias,
The server state cannot be read out via the DL_ReadNode module, as it is a flat buffer type.
Reading out flat buffer types is currently not yet possible for the customer, as libraries still have to be made available here.
Alternatively, you can read out the server state if you establish a UA client connection to the local host and use the module UA_ConnectionGetStatus.
In addition to the UA Server app, you must also install the UA Client app on the controller.
I have attached a project archive as sample code.

Many greetings


Established Member
Using UA Client to get the status of the server is just a workaround. Neccessaray Functionblock is requested for RM22.03.