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Not applicable

'Lost connection to the Server' Error

Hi,

Why do we get 'Lost connection Error' while accessing the applications from Access point. We are using AJAX and this really hurts, because if the users have made lot of selections and if they lost connection to the server, the selections get cleared off and the application re-opens automatically. I tested many situation and ruled out the below following cause for the 'Lost Connection to the server' error.

1) It was not due to any network problem, because once network is lost the application freezes up and the application needs to be opened again.

2) It was not due to any particular selection, because I am not able to replicate the error again with the same selection made again.

3) It was not due to 'Session Time out', because I have kept it to 1800 sec and I get this error in 15-20 mins(Sometimes) of accessing the application.

I am using QV 9 SR3. Can someone please help me to get rid of this error?

Thanks

10 Replies
Not applicable
Author

Maybe the number of licences in the server is full or perhaps the licencse cal was install in two servers in one network.

Regards

vgutkovsky
Master II
Master II

What web server are you running, QVWS or IIS? Does this happen from all computers or just some? This could be a packet loss issue, in which case you would need to do some tests using packet sniffers to see what's going on. Or...it could simply be a bug that was resolved by SR4: "27409: Lost connection to server when erasing a selection Ajax." If you have a development environment you can test SR4 on, that would probably be a good place to start.

Regards,

Not applicable
Author

Santhosh,

We are having the same problem with QV 9 SR2 with Ajax and have tested various setting changes and cannot get rid of the problem. The "Lost connection Error" is displayed on all user pcs after 30 minutes of inactivity. All of the QV setting are much higher than the 30 minutes. I worked with IT on various iis setting but he does not think that iis is in the mix because he can stop the service and QV still functions and gets the error. Have you fixed the problem and what setting have you changed. Thanks

Not applicable
Author

The only time I have ever seen this error with AJAX is when two or more users are connecting to the application using the same login. A user is clicking around the AJAX application, and when a second user logs in with the same credentials, it will reliably show the "lost connection" error. If you're seeing it happen intermittently after random amounts of time, it may be possible that another user is logging in with the same credentials that you're not aware of.

What type of authentication are you using? NTFS or DMS? Are the users automatically logged in with AD credentials, or do they have to type them in via a basic auth dialog box?

Version 10 has a graceful "session recovery" feature that retains a user's selections even between application reloads, but I don't think that is what is going on with you here.

Not applicable
Author

we use DMS and auto logon with AD

I am doing the testing and I only have one logon, i let it sit for 30 mins and when I click another button on the report i get the lost server connection error.

dirk_konings
Creator III
Creator III

i suggest to upgrade to SR6. A lot of bugs for AJAX are solved.

Not applicable
Author

I have had a similar bug - have a look at the Windows Event Viewer. Turned out the QVS was restarting (although very quickly) so it was hard to notice and this is logged as an error in the application logs in the Event Viewer.

The solution looks like it will be to upgrade but it would be useful to find the exact cause so you can retest on a later SR of QVS. My problem was specific to the use of user created bookmarks. 1 bookmark worked fine but add a few more and start using them and the QVS soon restarted (and gave me the same error you are experiencing). I would certainly add this to your testing and also include a few more collaboration tests around shared objects and such.

nathanfurby
Specialist
Specialist


Santhosh wrote:3) It was not due to 'Session Time out', because I have kept it to 1800 sec and I get this error in 15-20 mins(Sometimes) of accessing the application.


I had the same problem and I think my solution was to set the 'Possible session timeout' value to 0 and the 'Maximum inactive session time' to 7200 (2 hours).

Not applicable
Author

We made the following setting changes and we still gout the time out error.

I had the same problem and I think my solution was to set the 'Possible session timeout' value to 0 and the 'Maximum inactive session time' to 7200 (2 hours).

Our situation could be a little different that the others.

our QV server has both QV webserver and iis and we thought iis was running but if we shut down the QVWS we can not open QV. So our tech shut down the iis and our testing for the timeout problem was using QV webserver with AJAX.

Our tech had a problem request in with QV support and the following is their answer to our problem:

QVWS is hard coded for a 30 minute timeout for AJAX users. IE Plugin is not using the QVWS timeout. This will explain why all users connecting AJAX see the same symptom. This is working as designed.

Our next problem will be to try and see why iis is not working. any suggestions on trouble shooting, tips or good documentation for the iis setup

thanks,

ME