In order to successfully update the Filr or search appliance, the data storage location must be on a data disk, not the system disk. This is the VMware, Xen, or Hyper-V hard disk that you created in Section 2.0, Installing the Filr Appliance and Configuring the Operating System. (For more information about the type of data that is stored in the data storage location, see Section 1.1.3, Filr Storage.)
When you point the new appliance to the previous appliance data storage location, the new appliance detects that you intend to do an update. The Filr appliance carries forward the appropriate configuration data from the old appliance.