Unexpected session expiration

I developed simple Vaadin application - web interface to read and write some data in xml files.
After few munites of using application I get error “Session Expired” , in the console and log files there is no messages.
I thied different tips, like to add to web.xml:

30

or to add to context.xml

But without any success.

Can anyone help?
I do not even understand how to catch this error because there is nothing in the logs?
How to monitor session timeout and expiration in vaadin?

thanks!
P.S. if it is need I can sent sources of my application.

Hello,

I’m facing a similar problem in my application. The tomcat timeout does not work as expected. I’ve set it to 30 minutes, but the session does not timeout after this time.
Could this be caused by the progress indicator (poller) in the page?

Thanks and regards,
Dinko

If you are polling, yes, there is continuous activity, and the session will not expire if the user keeps the browser open.
If this is an issue, you may consider ICEpush instead.

I am facing similar issue of session expiry .

i tried this  

   <session-config>
  <session-timeout>30</session-timeout> 
  </session-config>

But above is not working for me . I am trying to upload files with uploadprogress monitor .But after few minutes session is expiring .