Problem with D2000 KOM process not restoring OPC UA connection after server restart

Support Forum
#1

Hello

I am using D2000 to monitor data through an OPC UA server & everything works fine until the OPC UA server is restarted . :innocent: After the server comes back online; the KOM process doesn’t automatically re-establish the connection & I have to manually restart the KOM process for data to flow again. :upside_down_face:

I have checked the logs & there’s no clear error message just a loss of connection. It seems like D2000 doesn’t always detect that the OPC server is available again. :upside_down_face:I have tried increasing the timeout and tweaking reconnect intervals but without much success. :innocent: I checked Configuration process - D2000 V23 Documentation - Ipesoft Confluence UiPath Course guide related to this and found it quite informative.

Is there a reliable way to automatically reinitialize / force reconnect from D2000 when an OPC UA server restarts? :thinking: Would love to hear if anyone has faced this and found a workaround or a proper setting to enable full reconnection handling.

Thank you !! :slightly_smiling_face:

#2

Please enable logging in the configuration of the OPC UA Line object (on 3rd tab, set “Communication tracing” to “Disk” or “Screen/Disk”) and attach the communication logs.
It would be useful to make an XML export of your configuration (OPC UA line, station, tags), zip these XML files, and attach them also.
Warning: They may contain sensitive information, e.g. IP address of your OPC UA server, username+password, so you might want to manually edit these files before zipping and uploading.

Also: how long did you wait after OPC UA server restart, till you restarted KOM process?
If you (after OPC UA server restart) perform on computer with D2000 server:

netstat -n | findstr a.b.c.d
(replace a.b.c.d by the OPC UA server’s IP address), can you see the TCP connection in the “established” state? I mean, does the Windows box with D2000 KOM process know that the TCP was closed (due to OPC UA server restart), or did you restart the whole box with OPC UA server (e.g. PLC), and Windows didn’t even notice this?
In this case, I would recommend setting “Max Pending Publish Requests” to some low value (e.g 2 or 3) in the configuration of your D2000 OPC UA Station object (the last tab). After sending as many “Publish Request” messages without receiving an answer, it will disconnect.