OPC-UA Client - Troubleshooting
Troubleshooting of the OPC-UA Client
Table of Contents
Error messagesInstanceItemF.A.QI cannot connect using username and passwordI cannot connect securely to a OPC-UA server but non-secure log-in works fineWhile we strive to deliver the easiest possible connection to your devices, all systems are fallible and here are some of the known issues
This article will describe some of the most common faults encountered when trying to connect using the OPC-UA Client. All the various error messages is also explained here.
Error messages
Both instance and items can have errors. These are shown on the portal and the following sections describes the error and how to solve them.
Instance
| Error message | Description | Solution |
|---|---|---|
| Could not connect to OPC server. Check connection and certificate (BadDisconnect) | The server is unavailable | Check the IP address and that you can ping it. Ensure that SIA is in the same network as the OPC-UA server and that it is running |
| Could not connect to OPC server. Check connection and certificate (BadConnectionClosed) | The certificate is not valid | Check that the self generated or uploaded certificate is correctly added to the servers trust list. |
| Could not connect to OPC server. Check connection and certificate (BadIdentityTokenRejected) | The username and password is invalid | When using a username and password, make sure that they match the ones set up on the OPC-UA Server |
| No suitable endpoint found, certificate rejected or wrong credentials | The client could not connect to an OPC-UA endpoint | Check that the endpoint is set up correctly (using SampleServer after the port in the address e.g. opc.tcp://localhost:51210/UA/SampleServer) and that the security mode that is selected is available on the server |
Item
| Error message | Description | Solution |
|---|---|---|
| Invalid Scalar type | The type returned is not yet supported by SIA | If possible, change the type to be a basic scalar type or possibly contact sales. |
| Item returned no value | The item you are trying to read had nothing in the value field | If possible, change the type to be a basic scalar type or possiby contact sales. |
F.A.Q
I cannot connect using username and password
In order to protect your credentials, you must use encryption when logging in with username and password. Set the Security Mode to either Sign or Sign and encrypt and select a security Policy as well (other than "None").
Make sure the certificate is accepted by your server if this is needed.
I cannot connect securely to a OPC-UA server but non-secure log-in works fine
Make sure your server has accepted the certificate that SIA presents. The OPC-UA SIA certificate is autogenerated at first instantiation of the connector and is therefore unknown to the OPC-UA server. See your OPC-UA server documentation for how to accept certificates.
You can also supply your own certificate and key and enroll this certificate in your OPC-UA server, See your OPC-UA server documentation for how to do this.