You can upgrade from Qlik Sense 3.1 SR2 to Qlik Sense June 2017 or later using the Qlik Sense setup program. Upgrading from any version of Qlik Sense earlier than 3.1 SR2 to Qlik Sense June 2017 or later cannot be done using the setup program. To upgrade to Qlik Sense June 2017 or later, see Upgrading.
You can update your Qlik Sense deployment by applying patches. A patch primarily includes software updates and fixes that are applied to the existing Qlik Sense version. For more information, see Patching Qlik Sense.
Upgrades and migrating persistence models
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.
You can upgrade from synchronized persistence to shared persistence if the existing deployment is running Qlik Sense version 3.1 SR2. See, Upgrading and migrating from synchronized to shared persistence.
When upgrading a central node from synchronized persistence to shared persistence, the existing repository database is shared with all nodes. If you want to setup a dedicated repository database on a separate machine, you must perform a new installation. For more information, see Installing and configuring PostgreSQL, and Installing Qlik Sense in a multi-node site.
Upgrades and centralized logging
Upgrading from Qlik Sense June 2017 or earlier provides the option to configure centralized logging through the installer wizard. Upgrading from Qlik Sense September 2017 or later does not provide this option. During the upgrade, centralized logging will be set up only if it was configured in the earlier Qlik Sense version. If centralized logging was not set up, the logging service will still be installed and running but without the database.