The Cluster Edition allows you to use inexpensive storage, such as local disks and file system devices, to provide instance-specific temporary space needs. You can use such storage, created as a private device, to create instance-specific local user temporary databases on the private device. However, do not use private devices for local system temporary databases. Local system temporary databases must be created on shared storage.
In the Cluster Edition, a private device is owned and accessed by one cluster instance only. That a device is private is a logical attribute; the physical path to the device may or may not be accessible from a non-owner instance.
In the sysdevices table, a private device is identified by the bitmap status2 column, and the instance that owns the device by the instanceid column of the row belonging to the device.
An instance can own many private devices, but a private device is owned by a single instance.
A private device can be used only for local user temporary databases, on the instance that owns the device. It cannot be used as default storage; if you invoke sp_diskdefault on a private device, the stored procedure fails and an error message appears.
A private device cannot be mirrored, unmirrored, or remirrored.
