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My MacBook Pro’s HDD seems to be on the way out—this is happening and disk utility said I should replace my drive so I’ve purchased a replacement. My current disk is 500GB with 287GB used. How can I safely copy all the files from my old one to my new one (also 500GB)?

I thought about using Disk Utility to create an image which would involve these steps:

  1. Mount the new disk via USB with an enclosure
  2. Create a disk image of the old drive using disk utility and put it on the new disk
  3. Boot from CD and open Disk Utility
  4. Erase the old disk so it is empty
  5. Move the image of the old disk back on to the—now empty—old disk
  6. Put the new disk in my laptop and the old disk in my USB enclosure
  7. Restore the image of the old disk from the old disk on to the new disk
  8. Boot off the new disk with all my old files now on it

My questions are:

  • Does the basic Mac OS, which you boot from DVD, allow you to read from USB drives and browse file systems so I can do points 5 and 7?
  • Isn’t it dangerous to have all my files in one image on my old (dying) disk with no other complete copy? I would prefer to directly copy from one to the other.
  • Could I use rsync to make a direct as-is copy from one to the other?
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What about simply using time machine and then backing up your files to that hard drive. Then, remove your old harddrive, insert the new one and ask to restore from the new Harddrive. – Josiah Oct 5 '12 at 19:56

You can actually image directly from one disk to the other. The OSX DVD might let you do this with Disk Utility, but with pretty much any linux live CD you can use a tool called dd

If /dev/sda is your internal disk, and /dev/sdb is the usb disk, you can do a bit-for-bit copy with

dd if=/dev/sda of=/dev/sdb

This will start copying data from the start of the drive and continue to the end of the drive, and you will have two exact, identical disks when it completes.

Then just swap out the drives.

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