logical volume management

There are two logical volume management packages commonly deployed in Solaris implementations. DiskSuite (newly referred to as Solaris Volume Manager) is available for free with the Solaris operating system. It is well-suited to hosts with a small (<10) disks with fairly static configurations. Veritas volume manager (commonly sold as part of Veritas Foundation Suite with Veritas Filesystem) is a third-party product that is better suited to more complex installations with larger numbers of disks. However, as we'll see, there are many installations that combine both packages on a single host.
Several factors are relevant in deciding which volume management tool to deploy. Because it's free, DiskSuite is a very appealing option for many hosts. It is also easy to administer and to install. However, Veritas volume manager should be considered for installations with more complex requirements, including:
Clustered installations with shared storage, in which Veritas diskgroups reduce the likelihood of filesystem corruption due to unintended simultaneous write access by multiple hosts.Installations with large numbers of disks. Though DiskSuite is certainly capable of handling a large number of disks, volume manager provides both graphical and text-baed interfaces that scale well as the number of disks increases.If there is a need to grow and shrink filesystems dynamically, Veritas filesystem is currently the only filesystem available for Solaris that allows one to shrink filesystems on the fly. Note, however, that one can purchase Veritas filesystem without Veritas volume manager as well.