If Qlik Server closed the connection with 'OnSessionTimedOut', keep the current behaviour.
But if the connection is just dropped, please redial. And when redialing, consider adding a console message: 'Webcosket connection lost. Reconnecting. (Happend 04:00 minutes since the previous lost connection.)' OR at least state the time when it happened.
In a complex network architecture, with multiple clouds, IT centers etc, timing the connection drop is the only information that can help you find the source. If it always cuts out after 4 minutes, you start looking at the Azure Gateway. If it always cuts after 2 minutes, you look in IBM WebSeal. If it varies, it is not a timeout setting, but a flaky network. Happy hunting. (But at least you know it is not a timeout setting, so you can skip investigating those.)
Qlik Sense Enterprise SaaS has a 30 second TCP keep-alive enabled for the WebSocket connection. This means that an ideal session will not be closed prematurely, with the assumption that the TCP keep-alive packages are honored by all network devices in the routed path.
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