OPC-UA Client driver troubleshooting

The following section lists common tasks, problems, and their resolutions for troubleshooting the OPC-UA Client driver.

The features and functions available in a node are controlled by the licenses that are installed in the node.

To verify that the OPC-UA Client driver license is installed:

  1. From the Workbench left pane, expand the node whose license you want to check, and then select the Administration icon.
  2. From the Administration window, select the Licenses tab.
  3. Select the appropriate license. Details of the license appear on the tab.
  4. View the Features field to identify the device driver.

If you do not see the correct license, or if the license is expired, you must request a license from your license key provider. 

For information on how to install a license, refer to System Administration > Licenses.

The OPC-UA Client driver is not part of this node's installation. The OPC-UA Client driver is installed as a separate package, separate from the base product installation. 

You may be working with different levels of nodes, each with different levels of support for devices. Ensure that this node is one with support for OPC-UA Client devices.

For information on how to add the OPC-UA Client driver package, refer to System Administration > Packages.

Ensure that the OPC-UA Server that you are communicating with is on the same network in which deviceWISE is installed.

Check to see if the OPC-UA Server is stopped and if so start the server. You may also find that the server is no longer installed, in which case the OPC-UA Client will not be able to start.

For more information, see Limitations.

Both the variable watch window and data triggers use UA subscriptions to monitor data changes. Each trigger and each variable in the watch window requires its own subscription. If the OPC-UA server limits the number of available subscriptions, it may result in read errors. Configure the OPC-UA server to allow more subscriptions.

OPC-UA servers support dynamic array sizes while deviceWISE does not. Modifying the array size after starting the OPC-UA client will cause read and write errors.

Not all OPC-UA servers support reading and writing to subsets of arrays. For these servers, reads and writes must be performed on the entire array.

deviceWISE allows variable location names to be a maximum of 128 characters long. The variable location consists of the parent structure names plus the variable name. A variable with a location name greater than 128 characters long will not be able to be accessed, and will return an "Error: Variable does not exist" error.

Renaming a variable to fit the 128 character limit will allow you to read and write to the variable.

The OPC-UA Client driver requires significant system resources to connect to OPC-UA servers and subscribe to the tags supported by the OPC-UA server.

For more information, see Limitations.

When the Subscribe To Tags parameter = Yes, the OPC-UA Client driver attempts to auto subscribe all enumerated variables using a rate value from the Subscription Rate(ms) parameter.

If the auto subscription fails continuously, check the following:

  • Check the OPC-UA Server supports subscription.
  • Check the OPC-UA Server supports the subscription with the selected Subscription Rate.

The OPC-UA error code value of 0x80100000 is returned by the OPC-UA Server indicating that a request sent by the client contains too many operations. A scenario where this might occur is when the OPC-UA Client is starting. The OPC-UA Client by default has a Max. Nodes per Browse value of 10,000. Some OPC-UA Servers are not able to handle requests this large, in which case they will return the 0x80100000 error code. To correct this error set the Max. Nodes per Browse to a lower value. As an example, internal testing for an OPC-UA Client connecting to the OPC-UA Server on a Siemens Sinumerik 828D required a Max. Nodes per Browse value of 20. Attempting to connect the client with Max. Nodes per Browse values larger than 20 failed, when the OPC-UA server returned the 0x80100000 error code.

Maximum devices supported is limited to 25 due to the limitation in the driver. The 26th device will be disabled on start with the Connect failed error.

Ext. Error Code Description
-33650 (0xFFFF7C8E) Certificate Untrusted. The certificate of the server is not trusted by the client. Move the certificate from /staging/uaclient/pki/rejected to /staging/uaclient/pki/trusted/certs
-33651 (0xFFFF7C8D) Certifcate security checks failed. The server does not trust the client`s certificate. On your OPC-UA server trust the Telit OPC-UA Client certificate.
-33662 (0xFFFF7C82) Server does not support endpoint settings. The OPC-UA server specified does not support your requested connection settings. Ensure that the server supports your chosen Security Policy and Authentication Setting

-33663 (0xFFFF7C81)

 Private Key given is invalid. This error occurs due to the following reasons:
  • The private key file could not be found
  • The private key does not match the given certificate
  • The private key password is incorrect.

Ensure that all the above issues are fixed before attempting connection.
-33654 (0xFFFF7C8A) Certificate hostname invalid. The host name in the server`s certificate does not match the hostname used to connect. Ensure that your Endpoint url is configured correctly using the hostnames/ip addresses listed in the Server`s certificate.

OPC UA Client devices require significant memory usage for starting and browsing for tags. When using multiple devices, this memory usage is multiplied and the memory is not released by the 3rd party OPC UA Client SDK until deviceWISE is restarted. If memory usage is limited on the deviceWISE node, be sure to properly schedule restarts of deviceWISE when multiple OPC UA Client devices are used concurrently.

Data Event Triggers that use OPC UA Tags utilize the OPC UA Subscription feature. This feature is implemented by the OPC UA Server that the OPC UA Client is connected. If the Priority setting selected when defining the Data Event Trigger is less than the subscription interval supported by the OPC UA Server, the Trigger will disable. Selecting a higher Priority setting in the Data Event Trigger will correct this problem, allowing the Trigger to Start.