Solaris Volume Manager volumes can be expanded. However, volumes cannot be reduced in size.
A volume can be expanded whether it is used for a file system, application, or database. You can expand RAID-0 (stripe and concatenation) volumes, RAID-1 (mirror) volumes, and RAID-5 volumes and soft partitions.
You can concatenate a volume that contains an existing file system while the file system is in use. As long as the file system is a UFS file system, the file system can be expanded (with the growfs command) to fill the larger space. You can expand the file system without interrupting read access to the data.
Once a file system is expanded, it cannot be reduced in size, due to constraints in the UFS file system.
Applications and databases that use the raw device must have their own method to expand the added space so that they can recognize it. Solaris Volume Manager does not provide this capability.
When a component is added to a RAID-5 volume, it becomes a concatenation to the volume. The new component does not contain parity information. However, data on the new component is protected by the overall parity calculation that takes place for the volume.
You can expand a log device by adding additional components. You do not need to run the growfs command, as Solaris Volume Manager automatically recognizes the additional space on reboot.
Soft partitions can be expanded by adding space from the underlying volume or slice. All other volumes can be expanded by adding slices.