Recovering information from disk is the ideal method because disk technology is random versus sequential tape. In addition, disk-based backup and restore (BUR) systems are more reliable than tape and with data deduplication the economics are so compelling that the market continues to explode.
While everyone talks about deduplication in the context of disk-based backup, the real attractiveness of this technology is disk-based recovery and the ability to lower RTO cost effectively by keeping more data on line longer. If disk space were free, data dedupe would not be used, because dedupe adds overhead. But disk isn't free, so dedupe has become an attractive way to trade a bit of extra time and complexity for a whole lot more benefit in terms of data recovery.
For mission critical applications, disk-to-disk BUR, with nothing in the middle to get in the way, is always the best solution. As such, data dedupe doesn't fit well here where recovery processes are hardened and reliable. Rather users should target dedupe at the fastest growing segment of data, unstructured and distributed information, and help business users put in place reliable recovery processes that work quickly with minimal IT effort.
Action Item: Aim data deduplication at two places:
- Where data is not backed up properly (e.g. remote offices and desktops). Here, consider source-based deduplication or managed services; and
- Backup applications where recovery is challenging, for example email or file services. In this case, target-based deduplication will likely be the best strategic fit.
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