A disaster can be anything which causes the Qlik Sense server to go down and lead to a major impact on the business operations. Today, no one can assure that there won't be any kind of disaster. A disaster could occur for any reason, like natural calamities, human error, malfunction of software, and so on. Thus, it is important that the Qlik Sense installations, especially ones with large-scale usage should have a disaster recovery plan.

Disaster recovery in Qlik Sense is nothing but setting up a mirror copy of the production install, along with the configuration setting and the data, on another server, typically located at different geographical area or in different network. This DR (disaster recovery) server will be configured to sync data from the production site at regular intervals to get new data and updates. This helps to reduce the downtime caused by the disaster, as DR instance is replica of production. The DR setup can be made active if primary site goes down. The activity should be scheduled in such a way that the end user should not be impacted much.

In case your production architecture is single node architecture with either shared persistence or synchronized persistence, you donᵩt need to worry much, because you have only a central node in the single node architecture, so creating a DR wonᵩt be that difficult.

When you have multi node architecture in production environment, with synchronized persistence, then you should create a backup for the machine where the central node is installed, because all the data from the rim node will be synced with the central node, and the central node is responsible for handling the repository database. With multi node architecture, if you have shared persistence, then you can take the backup of the node on which the repository database is installed and the shared folder.  

This backup strategy is the most effective way of doing the backup, but it requires additional investments and the hardware needed is equivalent or at least half the size of the production site server. So the cost impact in this strategy is high.

This type of backup can be planned when Qlik sense dashboards are critical to business and any downtime of Qlik Sense server impacts business operations.