A quick search on the Web provides endless results on the battle between virtual versus physical storage. Most writers seem to believe that the choice should be based on budget: If you have a large budget, you go with physical; if you have more limited budget, you choose virtual.
Leaving budget aside, these two approaches have fundamental differences that make virtual at least equal if not preferred to physical. Physical storage for the most part is the stronger performer, delivering higher I/O’s over the virtual appliances. However, that is not always true.
Creditplus Bank in Germany replaced its physical SAN which cost 10’s of thousands of dollars) with a Storage Virtual Appliance (SVA), the SvSAN from StorMagic, as an interim storage solution while it upgraded the expensive hardware. During this time IT noticed that SvSAN was delivering at least 25% higher performance on I/O’s: http://www.stormagic.com/pdf/Credit_Plus.pdf
This demonstrates that an SVA can perform at an equal level as physical storage (obviously under the right conditions, but that’s the same for physical), so what about general use? An SVA needs less tender loving care than the traditional physical storage, making it a great “set and forget solution,” decreasing the time IT staff spend fooling around with the storage and giving them more time doing stuff that matters.
As an SVA is not a physical piece of hardware which gets outdated as technology advances, which doesn’t take long these days, it’s able to remain updated without expensive maintenance or upgrade costs unless capacity requirements change.
Then bringing budget back into the discussion, an SVA is substantially more affordable than physical storage. For less than $2,000 you can achieve HA with two servers.
These factors make SVA’s like SvSAN, a simple set-and-forget solution which delivers high availability for business continuity that doesn't break the bank or sucking up your IT resources, a popular solution for remote and branch office multi-site environments.
Have a look at SvSAN: http://www.stormagic.com/svsan.php