Some low-level OPC UA settings like the maximum length of a transmitted string and the maximum number of concurrent sessions are maintained in the CogentDataHub.Config.xml file that gets installed with the DataHub archive.

This file can be edited to fine-tune these and other parameters for special situations. However, editing the file in the installation folder is not recommended, because any update of DataHub software will overwrite the changes, returning to the defaults.

In DataHub version 11.0.4 and higher, you can copy the CogentDataHub.Config.xml file from the DataHub installation folder into your configuration folder, and modify it there. The DataHub engine will check the configuration folder first, and if it finds a copy of the file it will load it. Otherwise, it will load the original file from the installation folder. In either case, the Event Log will indicate which file was loaded.