Storage Virtualisation
Overview
Direct attached storage and many SANs are primarily used for specific applications, with little sharing of resources and one-to-one relationships between LUN and application or file server. Falling hardware prices and rapid data growth have contributed to a proliferation of servers and storage devices, often from multiple vendors. This has resulted in islands of storage that cannot be shared and a typical utilisation rate of below 30%.
As server and storage estates have grown the cost of acquisition is being dwarfed by the cost of management and the rising complexity of protecting the data residing on the various storage devices. The issue of managing storage devices from multiple vendors can result in vendor lock-in, as users seek to reduce complexity - but at the cost of lost flexibility and choice. The ability to migrate data off old subsystems in a timely and cost efficient manner is also a significant issue, driving vendor lock-in and the inability to benefit from new technologies.
Storage Centralisation is the first stage of maturity in the storage environment that addresses the challenges of a distributed environment. A well designed, centralised storage solution should increase utilisation rates to approximately 50%. Complexity and management time is reduced as the number of devices is reduced.
Storage Virtualisation takes centralised storage to another level of maturity. Virtualisation separates the hard link between application servers and the storage subsystems attached to them by implementing a virtualisation layer between the two that provides a physical and logical separation. It is then possible to centralise the storage management tasks from individual, multi-vendor, disk subsystems to a single controller. As a result, individual islands of storage capacity can be combined to create a single pool of storage with a common management interface whilst increasing utilisation up to approximately 70%.
Key Deliverables
Increase storage utilisation rates up to 75%
Consolidate storage management tasks
Moving storage LUNS to a different area on the disk subsystem or to a completely different subsystem irrespective of vendor and disk type.
Increasing or decreasing the size of LUNS to ensure that provisioning requirements are correct.
Add capacity into the environment either onto the same physical disk subsystem or if required put a new vendors' disk subsystem into the environment.
Provide non-disruptive, simple migration within and between storage devices from multiple vendors
The performance and cost of disk must also be related to the cost and performance of connectivity. The difference in price between high performance fibre channel connectivity and iSCSI can be over 100%.
Build a service catalogue
A tiered storage infrastructure enables an organisation to build a Service Catalogue delivering storage resources with differentiated service levels and cost back to the business.
Vendor Alliances
