Although the concept of instant access to all data all the time is extremely appealing, the key is to balance needs against costs. Only the most critical data must be available immediately in the event of a network or system failure, and priority is best determined during business-continuity planning. Costs can be reduced significantly by backing up noncritical data to tape, optical disc and other offline storage systems as opposed to replicating data in real time throughout the enterprise.
Enterprise RAID solutions and other redundant SAN-based technology is not cost-effective for small companies with relatively few employees, but tape backup and low-cost NAS (network-attached storage) systems can do the trick in most cases. An accounting firm or medical office may need immediate restore capability, for instance, while a service business--an office cleaning company, say--may be able to survive longer without instant data access.
Large companies with hundreds or thousands of employees typically need significantly more robust--and more expensive--storage systems that comprise a variety of technologies. A RAID array can suffer a hard-drive failure without losing any data, but it won't do much good when data loss stems from fire, theft, virus or user error. Here again, tape-backup solutions are essential in providing recallable static storage that can reside on- or off-site.
Comparing Storage Options
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