Export to PDF failing in Confluence Server after upgrade from 6.4.0 to 6.13.4

[Roger Lynn]

All, My first question on the forum, so forgive me if this is misdirected.
I have raised a Confluence call on this, but no response as yet, so thought I'd ask the community.

Out internet-facing documentation in Confluence, is being upgraded to the latest Enterprise Release 6.13.4 (from 6.4.0).
We have upgraded a test instance first, and all looks fine, other than PDF export. When this is tried, even on a single small page, it hangs for several minutes, and usually fails with an 'Oops System Error' page (although very rarely it works and creates the PDF). This works correctly on 6.4.0 immediately before the upgrade.
Nothing is written to the Atlassian log until 60 seconds later, when the following entry appears:

[confluence.util.profiling.DefaultActivityMonitor] close Exceeded the threshold of 60000 ms: ActivitySnapshot{startTime=1557227386707, threadId=295, threadName='http-nio-8090-exec-9', userId='admin', type='web-request', summary='/spaces/flyingpdf/pdfpageexport.action?pageId=68357329'}

At some later point the following message (sometimes) appears:

javax.servlet.jsp.jspException: java.lang.RuntimeException: We couldn't complete your export. There are too many concurrent exports running on this node. <a href="https://docs.atlassian.com/confluence/docs-613/PDF+export+in+Confluence+Data+Center">Learn more</a>

I presume that this later error occurs if further exports are done, to exceed 'confluence.pdfexport.permits.size'. But the information in that link refers only to Datacenter.

I have checked out known issues and ruled them out for a variety of reasons (e.g. CONFSERVER-44995, we have no proxy).

Any suggestions gratefully received.

[David]

I have the same issue on 6.15.10. The docuemntation ponits to the Data center while I'm on server.

[it-service-frankfurt]

Same here on our 6.13.9 server instance (upgraded vom 6.3 to 6.13.4 to 6.13.9). Error message is pointing to Data Center as well.

There seem to be no PDF exports possible at all - looks like a bug to me.

[it-service-frankfurt]

Thanks David, you are welcome.

I have raised a ticket with the Confluence support today.