Virtualizing SAN Management Page 4
Simplifying SAN Management with Virtualization
The management of complex systems is simplified by the virtualization process. By separating the host (or server) view of a SAN from its physical implementation, virtualization technologies (which include both hardware and software) achieve simplicity. With attributes that are logical designators of storage, server, and network resources, system administrators can manage an aggregated pool of storage. Thus, system managers will be able to do the following with virtualization:
- Declare storage, processing, and network requirements for a business application according to predefined policies, and the virtualized network will support those requirements automatically.
- Automate business continuity plans through the use of explicit policies for mirroring, preparing, storing point-in-time replicas of data, and invoking failover procedures.
- Provide storage, processing, and network resources independently and on demand, without the need to specify exactly which storage device is allocated, which network path is utilized, and which server is processing the data,
Full virtualization integrates three distinct subsystems (storage, servers, and the SAN). This is a compelling trend in the evolution of the SANs.
- For servers, virtualization means the ability to adjust quality of services (QoS) for storage devices and the network while the server is executing on behalf of the application that it hosts.
- For storage devices, virtualization means hiding the details about the exact locations of data, the precise performance characteristics of storage devices, and available capacity.
- For the SAN, virtualization means hiding the details about the physical connections of network cabling, the allocation of ports, and the provisioning of appropriate bandwidth.
This trend toward higher-level server, storage, and network virtualization rests firmly on a foundation of lower-level hiding. Virtualization essentially means being aware of details within the automation processes but hiding them from the administrator. For example, different classes of devices with different performance attributes can be properly allocated to deliver differentiated QoS where needed.
The "instrumentation" provided by a foundation of network, server, and storage devices builds network management tools. In this case, instrumentation means that network switches, servers, and storage devices signal each other with critical, real-time operating data. These data are then standardized and made available to management tools.
In addition, a collection of application programming interfaces (APIs) known as Metadata, and other abstractions that map to the SAN's elements, will effectively constitute a SAN operating system. This particular operating system will support the financial accounting for storage services as well as for SANwide services such as automated provisioning of capacity and bandwidth.
Finally, as progress toward virtualized SANs continues, new and more powerful administration functions will emerge to mask the complexity and leverage the datacenter manager. Managers will be able to declare policies that regulate network and storage behavior.