But it had its downsides: SAN kit was expensive (particularly the SAN switches) and Fibre Channel networking was non-trivial to comprehend.

Not just the cost of purchase, provisioning of facilities, support staff cost and so on but form hidden things like power and cooling – all that had to be paid for.

These costs combined with the effort of swapping out existing equipment have created another issue: the rise of hierarchical storage models.

Rather than replace old or slower storage with new, faster systems it’s common to implement the systems for high-performance apps and demote the older stuff to tasks like file-and-print that don’t need the performance.

This can help you eke out a few years more use of the older infrastructure, but it leaves you with a multi-layer setup that becomes harder to manage as it ages and the number of layers increases.

Centralising your storage brings opportunities to de-duplicate data.

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