When working with an app in the hub, the connection to the app times out faster than configured in virtual proxy (for example, after 5 minutes), and the error message below is displayed:Connection lost. Make sure that Qlik Sense is running properly. If your session has timed out due to inactivity, refresh to continue working.
This issue occurs when accessing Qlik Sense through a reverse proxy or load balance, but does not
occur when accessing Qlik Sense on the same server (https://localhost/hub).
The user is also being active on the sheet, i.e. they are making selections etc. to interact with sheet objects.Environments:
- Qlik Sense Enterprise, All Versions
- Load balancer or Reverse Proxy in front of Qlik Sense
Network appliances may not see the websocket connection as an "alive" TCP connection, depending on the vendor, and therefore terminate the connection on behalf of the end-user.
Qlik Sense should not terminate a session earlier than configured in the Virtual Proxy (default is 30 minutes), and when it does the error message would be different: Your session has timed out. Log back in to Qlik Sense to continue.
In this case, if the connection is being lost and it is occurring sooner than configured in the virtual proxy then this indicates that either:
- The client is terminating the websocket connection prematurely, or
- A network appliance acting on behalf of the client (load-balancer or reverse proxy) is terminating the websocket connection prematurely
Is WebSocket traffic possible?
Qlik Sense requires WebSockets. To verify WebSocket traffic, see Qlik Sense Websocket Connectivity Tester
Enable TCP Keep Alive
Check to see if this issue occurs when using Internet Explorer. Internet Explorer by default adds additional unnecessary traffic to the websocket which can help in these situations. If you do not receive early timeouts when using IE, you can try turning on the Enabling TCP Keep Alive Functionality In Qlik Sense
If the above does not work, then you will need to make changes to your network infrastructure, unfortunately this falls outside the scope of Technical Support as this often is specific to the network involved. If you need further assistance, please reach out to your Account Owner to arrange Consulting Services (or see How to Contact the Consulting Team?