A disk set is a set of physical storage volumes that contain logical volumes and hot spares. Volumes and hot spare pools must be built on drives from within that disk set. Once you have created a volume within the disk set, you can use the volume just as you would a physical slice.
A disk set provides data availability in a clustered environment. If one host fails, another host can take over the failed host's disk set. (This type of configuration is known as a failover configuration.) Additionally, disk sets can be used to help manage the Solaris Volume Manager namespace, and to provide ready access to network-attached storage devices.
For more information, see Chapter 18, Disk Sets (Overview).