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I want to copy my entire hard drive to an external hard drive of equivalent size. I'm using a Mac, and I was thinking about booting Ubuntu so that I can use dd, but I'm not sure how to do that. If that's not possible/easy, other suggestions on how I can do this — without opening the Mac — are welcome.

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As techie007 pointed out you're probably better off with a cloning tool since they are considerably quicker due to not performing a bit for bit copy of all the empty space which tends to take a loooong time on large drives. – Col Sep 2 '11 at 20:59
Is there something specific wrong with /bin/dd that's part of a normal OS X install? – Wooble Sep 3 '11 at 20:27
@Wooble, that I cant use it on the harddisk I boot from. – Dani Sep 3 '11 at 22:23
up vote 0 down vote accepted

I use this SuperDuper for this on my Mac:

It takes care of making sure the permissions are correct and the copied volume is bootable. It also supports 'sync' so you don't have to do full copies for backups. I actually use this instead of time machine because it creates a fully bootable copy of my data unlike time machine which you still have to reinstall the OS and then restore your data to get back up and running.

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Your best bet for using dd without wiping your existing OS may be to boot from a Linux LiveCD.

There is a list of various ones you can check out over at

There are also other programs like CloneZilla, and DriveImageXML that may be worth looking into as well (they are made for cloning hard drives).

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When you say, "without opening the Mac", do you mean physically removing the drive or not turning it on?

If the computer can boot, you can run carbon copy cloner from a thumb drive to another external hard drive.

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Yes, I mean physically open it. I cannot get ubuntu to boot on the mac, is there any other cloner that can boot on mac? – Dani Sep 2 '11 at 21:52

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