11 Replies Latest reply: Apr 26, 2016 5:42 AM by Michael Ionkin RSS

    "Connection lost" problem if use different clients

    Michael Solomovich



      Here is the problem:
      I open a server-based QV application using QV Desktop.  Next, open another session with AJAX client.  When I'm switching between these two clients, getting "connection lost" message and have to reopen.  Well, AJAX reopens by itself but still a problem...
      No problems if both sessions are Desktop (or Plugin), or both are AJAX.  But the ability to use Desktop and AJAX at the same time by the same user is a requirement.
      Is it possible to eliminate "lost connection" in this situation? 


      Thank you,

        • Re: "Connection lost" problem if use different clients
          Rob Wunderlich

          I believe the answer is "No", unless you either allow Anonymous or give a different userid for each session.


          Are you trying to open a session on the same document or another document?


          When opening the same document, the problem is that Session state is maintained per userid. Those two clients use different mechanisms to identify machine/client/session, so they cannot converge on one session.


          Similar problem using Named CALs. Named CALs are only allowed one one "machine" at a time. The different id mechanism (Desktop=mac address, Ajax=cookie) look like two different "machines" to the QVS.


          Only workaround I've seen is to open the sessions with different userids.



          • Re: "Connection lost" problem if use different clients
            Peter Cammaert

            This is a funny situation.


            Keeping two regular client sessions open using a single CAL on two different machines or on the same machine with two different client types should be possible. But not three.


            Could it be that you leased out that same CAL to your desktop at the same time? Because that would leave only one active client session which will jump from AJAX to Plugin/Desktop AP client and vice versa (leading to those  "lost connection" messages on the session you just left)



              • Re: "Connection lost" problem if use different clients
                Michael Solomovich

                Thanks Peter,


                But, how you explain the "lost connection" issue in case when one session is in AJAX and another in a licensed QV Desktop?  No CAL lease in this case.

                Situation is a little better when QV Desktop is licensed and the clients are Plugin and AJAX.  Only AJAX client loses connection, but never Plugin.  Still not acceptable.

                What else I'm missing?

                  • Re: "Connection lost" problem if use different clients
                    Peter Cammaert

                    "...one session is in AJAX and another...". A licensed QV desktop is (if not licensed by way of a local license) at the same time "using" your CAL 1 time (if you use it as an AP client wth Open in server) and leasing your CAL, i.e. transferring the CAL for offline use in the regular development environment. That means your two usages are gone.


                    The second situation is weird, as the plugin should loose its connection as soon as the AJAX client opens a document. Maybe it isn't visible immediately. I've never heard of a "Connection Lost" dialog in QV Desktop.


                    The same thing can happen with the QV Desktop itself, when another desktop tries to lease a CAL a second (or a third) time. The difference is that the first desktop will fall back to PE mode.


                    This is tricky stuff, and based entirely on experience, not on the content of some secret theoretical QlikTech document. Moreover this behavior can change between SR-releases. The best thing you can do is set-up a few simple but essential combinations of clients and desktops, and test them out. IMHO it all comes down to:

                    * same login, same machine, same client: do what you want (as many browsers with a session each as you like)

                    * one of the above is differen: 2 sessions max.


                    Good luck,



                • Re: "Connection lost" problem if use different clients
                  Michael Ionkin

                  Hello Michael


                  i have a similar problem and maybe you can help me out here.

                  There are several users in our enviroment and they open documents mostly with QV Plugin (in future only Plugin).

                  They are experiencing often the issue with lost conn to server.


                  I've already unchecked the following option on QV Management Module "Allow Only One Copy of Document in Memory" , but the problem occures still (i currently measuring wheter the occurence intervall got smaller by now)


                  The same qvw document is opened by same users diff mashines and/or diff users diff mashines.


                  Shell I change any setting in document properties? (like Refresh during session; Client triggers refresh; server triggers refresh..)

                  I want that same users do not share a session on the same document.


                  Is that possible? (Only NamedCals are avail)



                  Thank you in advance