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I have a few external ssd hardrives (My Passport, in my case). I would like to integrate them within a system that provides reliability in case of failure, by producing redundant information across the devices, seamlessly from the User point of view.

What would be a product worth considering?

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up vote 2 down vote accepted

First let's clarify one thing: RAID is not the same as backup. Building a RAID array out of several (presumably USB) external drives would have many drawbacks. See this question I asked a while back for the explanation. I suspect what you really want is passive and seamless disk/data backup in which case OS X's built-in Time Machine works great. And if you have Mountain Lion it is capable of using all of your external drives to store the backups.

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are you saying that with TM, if I have 2 or more drives, it will take care of creating redundant data? – Bob Mar 7 '13 at 0:07
@Bob I am saying that on Mountain Lion Time Machine will spread the backups across both drives. I do not know the algorithm used to do the spreading. I just know that TM can use more than one drive. – HairOfTheDog Mar 7 '13 at 0:13

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