The OPC Diagnostics Window provides a real-time and historical view of OPC events that occur between any OPC DA, OPC UA or OPC HDA client and the TOP Server. An event is a method call that a client makes to the TOP Server, or a callback the TOP Server makes to a client. You must be in Runtime Mode in the Configuration to be able to access the diagnostics. See Offline Editing for more information.
The OPC Diagnostics Window is separate from the main TOP Server configuration window, which allows you to hide the window even while diagnostics are being captured. In the event that there is an issue between an OPC client and the TOP Server, the Diagnostics Window can be opened to display the events that have occurred. The operation of the OPC Diagnostics Window can be controlled through its’ menu, toolbar or by right-clicking in the Event Window.
To determine the meaning of the data presented by this window, it is necessary to refer to the relevant OPC specifications (i.e. OPC DA, OPC HDA or OPC UA). Copies of these specifications are available to OPC Foundation members on the OPC Foundation web site (Information on joining the OPC Foundation is also provided).
See the TOP Server Help file under “Built in Diagnostic, OPC Diagnostics Viewer” for information on how to use this feature including settings and filters for the different specifications.
The OPC Diagnostics can also be persisted to file. For OPC UA, this must first be enabled under File -> Project Properties -> OPC UA, as shown below:
The actual persistence settings for TOP Server OPC Diagnostics are under the TOP Server Administration settings, under the Event Log tab, as shown below:
OPC Diagnostics Log Settings:
Memory (no persistence) - The default option follows the legacy behavior of OPC Diagnostics and diagnostics are not persisted to file in this mode.
Single File - All diagnostics records will be persisted to one file only.
Extended Data Store - Enables spanning of diagnostics records across multiple files based on the other settings.
Max Records - Maximum number of records that the log can contain before the oldest records start being overwritten (Only available for Memory or Single File modes).
Log File Path - File system directory where log files will be stored.
Max single file size (KB) - Maximum size in KB that any one log file can contain. (Only available for Extended Data Store Mode).
Min days to preserve - Once log files are older than this number, they will be deleted. (Only available for Extended Data Store Mode).
The OPC Diagnostics window can be accessed under View -> OPC Diagnostics in the TOP Server Configuration.
To specifically troubleshoot only OPC UA communications, the full set of filters are provided for enabling/disabling calls for OPC DA, OPC HDA and OPC UA. From the OPC Diagnostics window, go to Diagnostics -> Filter. By highlighting OPC DA and clicking “Uncheck Selected” and then also OPC HDA and clicking “Uncheck Selected”, you can restrict the diagnostics capture to only OPC UA events.