Unexpected Exception: Unknown Client Notice in Alarm Console

Solved956 viewsstack trace unexpected exception unknown client
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Hi Dojo,

I've been noticing this type of warning in Alarm Console, not too frequently, but present every now and then: any info on what type of client can produce this?

I'm troubleshooting in 9.6, due to a leak in SLLog while the system gets upgraded to fix the latter.
Aiming at limiting errors till the imminent upgrade.

Thank you

Marieke Goethals [SLC] [DevOps Catalyst] Selected answer as best 12th July 2023

1 Answer

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Hi Alberto,

This specific error indicates a mismatch between the list of logged in users as known by the SLDataMiner and SLNet processes.

In this case, it's basically SLDataMiner receiving a request from user X to receive parameter changes updates, while SLDataMiner doesn't now about user X being logged in (anymore or yet)

The impact is probably low. This might be a race condition when a client disconnects and still has subscribe-requests queued (just guessing here).

Marieke Goethals [SLC] [DevOps Catalyst] Selected answer as best 12th July 2023
Alberto De Luca commented

Thanks for your answer, Wouter.
Could this message be triggered also by an old istance of the Asset Manager?
Wouter Demuynck [SLC] [DevOps Advocate] commented

I don’t believe Asset Manager is involved here, as it only does database queries. It doesn’t subscribe on parameter value changes.

Having the message generated is certainly a bug. To find out more about what exactly triggered this message, further investigation using a full set of logging from around the time where the notice was triggered would be required.