Software to sync two external hard drives?

jarrrp

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Jan 5, 2012
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At present, I have one 1TB portable hard drive which stores all of my photography on it. It's mostly just a hobby at the minute so this comfortably supports all of my work. But I recently realised I'm living on the edge only having one copy of all of my images so I needed to look into getting another hard drive. I've decided on an external desktop hard drive as a master back up, however I want the contents of my portable hard drive and the new hard drive to be exactly the same. I'm wondering if you guys know of any software which will allow me to plug both hard drives into my MacBook every so often and get the desktop drive to copy any differences in the portable one (which is the one I'd use to work on and then later back up to the desktop hard drive). Or if you know of any better ways of basically creating two identical hard drive back ups which can be frequently synced.