"...virtualization is popular because it helps IT organizations get more out of their existing hardware investments. In order for storage virtualization to be equally as popular, the tools that are brought to bear need to provide an equal level of instant benefit. Right now, the only thing that does that in the realm of storage virtualization is a software-only approach to creating virtual pools out of existing storage investments."
...The folks at DataCore, which makes software that allows IT organization to turn existing storage arrays from multiple vendors into a shared pool of disk storage, have two theories about why storage virtualization is evolving much more slowly than server virtualization.
The first theory is that most storage hardware vendors require customers to buy new storage arrays that support storage virtualization. In these difficult economic times, it's hard to make an argument that basically says an IT organization should spend a lot of additional capital now in order to save money later.
The second theory is that when IT organizations introduce storage virtualization, they are worried about performance penalties. Too often there are database and e-mail applications that don't perform so well when virtualization is introduced. To specifically deal with storage virtualization performance issues, DataCore is now adding aupport for up to 1TB of cache to a new 64-bit implementation of its SANmelody 3.0 and SANsymphony 7.0 software.