Connection cache generation error

[StephanB]

Hi all,

We are experiencing an issue on our nPrinting server where it isn't able to refresh any connection's (to our QlikSense server) metadata.  Existing and unchanged reports are still able to get data from Qlik, so that is not affected, it is only when you need to refresh the cache to get new Qlik objects onto the nPrint side that the Cache rebuild task fails.

It fails with the following error message:

Execution startup failed: could not delete: [Qlik.NPrinting.Repo.Model.DataConnectionFieldValue#b5c8cb1c-da50-42ad-8673-2b8b213b918f][SQL: DELETE FROM data_connection_field_value WHERE Id = ?]

We have re-exported new QlikSense certificates, and imported it on the nPrinting side, as well as checked that the nPrinting service account is configured as rootadmin on the Qlik side, to no avail.

Only possible cause we can think of is password updates to the Qlik and nPrint service accounts.  (Note the exported certificates were exported without any passwords specified)

Any ideas of what we could still try?

(Qlik version: Qlik Sense November 2021, qliksenseserver:14.44.5)

(NPrint version: Qlik NPrinting May 2021 SR3, Version: 21.14.7.0)

[Ruggero_Piccoli]

Hi,

Please open one of the affected connections and do a Run Verification. Post the screenshot of the error.

Check also the Qlik NPrinting log files to see if there are other error messages.

Best Regards,

Ruggero

[StephanB]

Sorry, seems as if my reply went missing, let's try again:

Here's the verification result from one of the failing connections:

Nothing special there

[Ruggero_Piccoli]

Hi,

Thanks. We cannot solve this via community post. We need to check your repository so, please, open a support ticket, and include a link to this conversation and the backup of your installation if possible. 

Thanks.

Best Regards,

Ruggero

[Frank_S]

@StephanB 

Is this the only connection affected?

Have you tried to open the underlying Qlik Sense app in the Hub? Are there any issues attempting to open the app?

Can you check the app for unsupported items?

--Unsupported Qlik Sense Items

Does the app contain section access and if so, are all the app objects fully published. This is a requirement for Apps that contain section access:

--Connecting to Qlik Sense apps with section access

The other option is to upgrade the NP server to May 2022 SR 3 as upgrading may also resolve the issue if the above do not.

Kind regards...

[andregas]

Hello @StephanB ,

It seems an NPrinting Repository error.

Try to check the NPrinting webengine logs at %ProgramData%\NPrinting\Logs\nprinting_webengine.log.
Probably you should enable debug level of log: https://help.qlik.com/en-US/nprinting/May2022/Content/NPrinting/AdministeringQVNprinting/Logging.htm...

If webengine doesn't collect any info about it, you should read the postgres log, but NPrinting disables it by default and I suggest you to contact the support.

Regards

[StephanB]

Morning people, sorry about the lack of feedback.  Two of my replies has gone missing, I suspect it is due to special characters in the log files entries that I am posting.  So I will rather post a screenshot of the error.  

So this is what I found in the nPrint logfiles (c:\Programdata\NPrinting\Logs\):

nprinting_engine.log seems clean around time of failure;

nprinting_webengine.log seems clean around time of failure;

nprinting_engine_cef.log seems clean around time of failure;

But...

nprinting_scheduler.log shows the following error around the time of failure:

It reports 4 consecutive blocks being corrupt in this relation base thingy: 16678,16679,16680,16681?

Hope this gives some insight

(Thanks in advance to all)

[Ruggero_Piccoli]

Hi,

Yes, I also think it is a wrong row related to a previous cache reload still stored in the Repository and that cannot be deleted for an unknown reason. 

Manually updating the Repository database could damage it more so better to ask for the help of an expert and always make a backup before doing anything. 

Plus we want to investigate and understand the cause of the error. So open a support ticket, thanks.

Best Regards,

Ruggero

[Frank_S · Accepted solution]

@StephanB 

I am going to make one more suggestion as per the steps below:

1. Make sure to publish all sheets and sheet objects required for NPrinting reporting purposes (speak to each app owner/developer and ensure all objects are published)
2. Duplicate and export the App (this will remove any private sheets remaining)
3. Create a a test NP connection (in the same NP App) to the duplicate Qlik Sense app.
4. Reload the connection

Does the test connection work? 
IF yes then recommend using the duplicate app in your existing production NP connection.

The root cause could be a problem in one of the Qlik Sense private sheets that's blocking the NP connection from working/reloading normally.

Kind regards...