Background Information for Expanding Slices and Volumes

Solaris Volume Manager volumes can be expanded, but not shrunk.

• A volume, regardless if it is used for a file system, application, or database, can be expanded. So, you can expand RAID 0 (stripe and concatenation) volumes, RAID 1 (mirror) volumes, and RAID 5 volumes as well as soft partitions.

• You can concatenate a volume that contains an existing file system while the file system is in use. Then, as long as the file system is UFS, it can be expanded (with the growfs command) to fill the larger space without interrupting read access to the data.

• Once a file system is expanded, it cannot be shrunk, due to constraints in UFS.

• Applications and databases that use the raw device must have their own method to “grow” 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 device. 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.