NPrinting Engine(s) failed to open document

[rafalcqlik]

Hi all,

NPrinting: Feb 2021

Qlik Sense Aug 2021 Patch 2

Since today we are having issues with opening some of the apps from Nprinting. The whole setup worked fine for months, nothing has changed recently. Connection verification works fine but when trying to refresh metadata, the process either hangs for very long time or it throws an error. In both cases, in the log file we see:

Qlik.NPrinting.Engine 21.0.0.0 Qlik.NPrinting.Engine.Consumer.ConnectionResolvers 20211220T064906.703-05:00 WARN [server-name] 0 0 0 0 0 0 0 0 Failed to open a resolver for connection navigator=qliksense;proxyurl=https://qliksense-server-url.com/winauth;appid=4c4723de-e763-426d-9e02-ab0bc85c8126;identity=DOMAIN\SERVICE_ACCOUNT. ERROR: System.TimeoutException: Method "OpenApp" timed out

(full message in nprinting_engine.txt file)

We do use section access in this app but removing it doesn't change anything - still the same error. Besides, on connection, option "Apply user section access for reports" is NOT selected.

What's interesting is that when we duplicate the app (QS app) and publish it again in the same stream, without changing anything in the app itself (duplicate > publish) we can generate metadata for that new app. Connection setup is exactly the same.

Any ideas?

[Lech_Miszkiewicz]

Hi 

First of all this configuration is not officially supported as NPrinting Feb 2021 is not certified to work with Qlik Sense Aug 2021. This is where I would point you to typical https://help.qlik.com --> https://help.qlik.com/en-US/nprinting/February2021/Content/NPrinting/DeployingQVNprinting/System-req...

and this is where conversation typically ends as we dont know what is causing this issue and it simply can be incompatibility. I often point the fact that solution can work for months and then suddenly stop working and the reason can simply be unsupported configuration.

As far as troubleshooting goes with this though. Difference between duplicated-published app and your current one is that your users could have created their own sheets it in the present one? Maybe there is is something what is not supported in it? Extension?

Or when you say "duplicate app and publish" you actually mean duplicate --> publish&replace existing app?

cheers

Lech

[rafalcqlik]

Hi Lech,

thanks for reply. We will upgrade to newest version after year end but at this point we have to work with what we've got 😉

There are no community or private sheets in original app - application is published in special stream which is available only for admins and developers. App is separated from other apps and is used only for Nprinting purposes (cleaned and stripped from unecessary objects, fields etc.). No extensions, straight tables only. By duplicated and published I meant published as a new instance (new app id). The old one is still there and it still doesn't work. We decided to simply change existing connection in Nprinting to point to that new app id and that solved the issue. We could do that because app doesn't have any community/private objects so nothing has been lost. We also have some reports in Nprinting that use regular apps (and normal users have access to them) with community sheets and that would be a problem if we would have to duplicate those apps to fix report generation. 

Interesting thing - we have multi node environment and we tried to point that problematic nprinting connection to RIM-2 and then cache was sucessfuly generated  although reports failed with applying filters error. Anyway, it looks like something is stuck for service account user on sepcific RIM for that application? Very weird. 

We restarted nprinting services and it didin't help. We couldn't restart Qlik in production so don't know if that would help.

I think we've had similar situation in the past but only during one weekend - reports were failing with the same error but on Monday it was all fine so I assumed there were some connectivity issues and ignored that 🙂

Rafal

[Lech_Miszkiewicz]

Hi @rafalcqlik 

i see what you mean and yeah - strange one. 

Qlik Sense:

• Have you checked Qlik Sense logs from the time when you tried to execute report?
• Also I always check Windows event viewer for network errors, antivirus issues, firewall changes or group policies changes
• Last one - obvious - resources RAM/CPU/HD space on Qlik Sense server when you tried to run this report, any reloads going on during that time? 

NPrinting:

When you run connection verification - do you get all checks green?

[rafalcqlik]

Qlik:

Unfortunately I do not have access to Qlik logs - would have to ask platform team to provide me something. I also cannot check event viewer... But when it comes to resources on the server then I do now that it was all as usual. No issues with RAM, CPU or disk space. Besides, we've had that issue whole day yesterday. During the day many other reports were running without problems and some of them were much, much bigger. Plus, everything was working with the exact copy of the same app.

NPrinting:

Yes, all checks green in connection verification. And it doesn't matter if connection was using service account or mine user - verification was fine but timeout opening app when generating cache.

We'll upgrade nprinting when possible and will see. If the issue will happen again then we'll probably report that to Qlik Support.

Thank Lech for all your help!

Regards

Rafal