Different virtualization approaches

Storage based, or array based virtualization, which would be vendor specific by nature, is not as far reaching from a storage management perspective as would a fabric based virtualization approach. Since most shops use storage supplied by multiple vendors, managing that storage becomes a chore unless each vendor provides an open management API, which can be accessed through a framework (the single console method). Most of the storage vendors today provide some sort of virtualization in their arrays in order to simplify LUN presentation and expansion. Some methods are better than others. The idea here is to keep storage management simple and cost effective.

There are many fine products out there that provide value in their individual approaches on how to provide storage resources to servers. You are correct in stating the fact that there are really three approaches to storage virtualization. Storage based, host based and fabric based. I take the storage-based approach for granted, as without that, an individual array does not provide as much value as would say a simple JBOD rack of disks. The reason I mention the other two approaches more often is because that is the place where custom

Although, if you only use one vendor's storage, then that vendor's management software may be all you need as long as it covers all the bases. My customers always tell me though that they need the capability to manage anyone's storage, no matter where it is located in the enterprise, using a framework that provides true and total resource management (security, performance monitoring and reporting, allocation control, rules, alerts, etc.) They need this from an application perspective, a fabric perspective AND a storage perspective. And, this needs to be implemented at a level above the individual disks that are presented in my opinion.

Chris

Editor's note: This question is in response to one of Chris' earlier Q&As.