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Rethinking process and ownership|
Avoiding gross levels of inefficiency requires bringing the storage provisioning function back into balance. This entails a two-pronged effort: considering the operational impact of virtualization to storage and the changes needed in terms of process and possibly responsibility/ownership; and identifying areas where newer technologies may be of assistance.
Virtualization technologies, and vendors such as VMware, introduce an additional layer of storage management that, in effect, causes a storage admin to cede some aspects of control regarding how storage is allocated, monitored and managed. The diagram titled "VMware storage provisioning steps" (below) outlines the provisioning process for a VMware environment, starting with the initial storage selection and LUN creation by the storage admin.
What stands out in this diagram is the additional management layer between the storage and the (now virtual) server. The storage admin hands off large disk volumes to the VMware admin to be used as VMFS containers, but the real disk allocation and server assignment responsibilities rest with the VMware admin.
The VMware admin provisions virtual machines (typically based on standardized configuration templates) and assigns standard-sized virtual disks (VMDKs) in accordance with the template definitions. There may be several templates based
| on defined server configuration profiles. This enables cookie-cutter provisioning and allows for some customization.
Finally, the VM server admin manager configures and assigns the volume. However, what's often missing is the end-to-end visibility to this storage, and how efficiently it's being reallocated and utilized at each level.
This can have implications for storage management with regard to tiers, data protection requirements and storage efficiency. Policies regarding the allocation of storage to apps based on service level and business value can become muddied or lost in this process and must be revised.
To maintain efficiency, operational standards are required. Many organizations are in various stages of establishing ITIL-like frameworks. The need for appropriate metrics is critical not only at each administrative layer, but across their intersections. Storage management is continually under pressure to contain costs, which to a large extent means controlling growth. Without visibility into the upper levels of the supply chain, this becomes an impossible task. It should be noted that the coordination issue impacts not only provisioning, but most other data management functions, most notably backup and DR.
This was first published in May 2008