And that's all fine. Except, what happens if the Enclosure does fail? Sure, you have your USB Drives with the Data etc.

But even after attaching these onto a PC, switching your various Media Servers to read the USB Drives, rather than the NAS is hardly a seamless or easy switchover.

Likewise, many people here are talking about Large NAS Storage.

Take for example a soon to be typical 4 bay by 3Tb NAS (even 5Tb Drives soon enough) allowing for Raid overheads, that's about 9Tb (or 15Tb) of Data. Say 3Tb of Music and 6Tb or more of Movies.

In that scenario, how do you EASILY back up that amount of Data; multiples of USB Drives hardly qualifies.

IMHO and experience, Back to Back NAS Enclosures offer the best combination of Protection, Backups and Seamless Transition in the case of enclosure failure .

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