Like we found on help.qlik.com :
Qlik Sense June 2017 or later only supports the shared persistence model. It does not support the synchronized persistence model. When you upgrade your Qlik Sense 3.1 SR2 deployment to Qlik Sense June 2017 or later, you will be migrated to a shared persistence model.
So the Shared persistence is the only solution but it has a strong limitation :
Shared persistence does not support geographical deployments, as Qlik Sense servers need to be located in the same local network as the database and the file share.
Does it mean that geographically dispersed site architecture is not possible ?
Is the only solution is to manage different sites ?