Looking for a better understanding of the error we encountered in Kepware:
"<DEVICE> | The following errors occurred uploading controller project from device. Resorting to symbolic protocol."
We had an issue in our plant where connectivity between Kepware and several Allen-Bradley PLCs were dropping out intermittently due to a networking issue. Approximately 3 minutes after this event started, we saw the above error message posted for all PLC's involved. While the message states the "following errors occurred" we never saw an actual message with details. Just the line above.
For context, all PLC's involved were originally setup with Logical Non-Blocking addressing. Kepware changing/resorting to using Symbolic addressing appears to have overwhelmed a combination of the PLC, network and driver. We were unable to recover until we restarted the Kepware server.
We've seen Kepware make the switch to Symbolic addressing when controls engineers are actively in the program, but we usually see an entry in the logs. Also we also see addressing is changed back to Logical when controls closes the program. In this case, no entry was made in the logs stating controls was online at this time. We've attempted to find additional information on the error code but have been unsuccessful so far. Hoping the community may have some kind of explanation.
- What condition causes Kepware to resort to using Symbolic addressing (other than controls going online with the program)?
- Is there a way to revert Kepwares decisions to using Symbolic addressing without having to restart the whole service?
