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How can I move my OSX Lion installation from my 500GB HDD, to my new 250GB Solid State HDD?

Re-installing OSX Lion is not an option.

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up vote 4 down vote accepted

there are a few solutions but the 2 most usefull to me are these :

for both solutions you'll need an SATA 2 usb enclosure or something like that

you can use an app like carbon copy cloner to make a copy on the new ssd and then just replace it.

or you can boot from a OS X dvd and use disk utility to clone the drive

select your language. Don’t worry: You're not installing Mac OS X again - this is just what you have to do to get to Disk Utility. When the menu bar appears, select Disk Utility from the Utilities menu.

When Disk Utility opens, you'll want to select your source. This is the hard drive you want to clone . After you have a source, select the Destination. This is the ssd you want to save the backup image to.

Click Restore and you'll end up with a perfect copy of your hard drive.

Replace the drive with the SSD and your good to go

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Is Disk Utility capable of cloning drivers of different sizes? Especially from a larger disk to a smaller one ? – Karolos Feb 16 '12 at 16:38
it should , it won't take in account the free space – Manuel Feb 16 '12 at 20:35
Even if the data is cluttered around in the larger drive? It's not a clone then. Do you have some reference of this? That would be great to know :) – Karolos Feb 16 '12 at 20:37
you could defrag before you make the image (clone )with a third party app butt it shouldn't be a problem if you didn't. I have tried this HDD /SSD shuffle for a few off our clients and it worked every time using the disk utility method. – Manuel Feb 16 '12 at 20:46
Thanks for confirming that you can do this from a larger disk to as smaller one. Your method is then much easier than mine. I thought that you needed to make a file-copy given the difference in size. – Karolos Feb 16 '12 at 20:55

You can create a Time Maschine Backup on an external drive, plug the new HDD in and boot from the install DVD while the Time Maschine HDD is connected to the system. The installer will ask you if it should use the data from the Time Maschine HDD. After you did this, everything will be exactly like on the old HDD and no more configuration has to be done.

OK, this comes close to a new installation, but at least it should be bullet proof and you will have everything like before.

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At this point, you can just get data from the old install; no need for a Time Machine backup. – Karolos Feb 16 '12 at 14:43
If you have a Macbook Pro you can only fit one internal disk. The Time Machine method works well in this case. – Martijn Heemels May 11 '12 at 19:05

For me, OSX Lion, trying to clone my 750 Gb HD to an external 500 Gb using Disk Utility, didn't work although only some 250 Gb were actually in use. While the cause to this may be an error on my side, some people might have the same problem..

The solution was to shrink the Macintosh HD partition on the local disk to a size smaller than 500 Gb using Disk Utility which is quite a fast process. After doing this cloning to the 500 Gb external disk went without problems.

Hope this is helpful.

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How did you shrink it? I didn't see this option in Disk Utility. – Scott Willeke Apr 4 '15 at 4:05

I just did this. I got a 256GB SSD for $175 and installed it in my late model 17" Macbook Pro. I then took the 750GB 7200RPM hard drive and installed it in the optical drive bay using this tray / adapter...

I had already formatted the new SSD in a USB enclosure.

When I rebooted, the machine found the regular hard drive now in the optical bay, and booted Mac OSX from it like normal. Both drives are available in Finder. Write tests, read tests and running a VM from the SSD worked fine.

I rebooted the machine, and held down [Command] + [R] to boot into the Restore utilities. Ran the Disk utility and used Restore to copy the contents of the hard drive to the SSD. I had removed all of my virtual machines from the hard drive first, so there was only 136GB of files on the hard drive. Transferring that to the SSD took about 30 minutes.

After the copy to the SSD completed, I ran the Startup Disk utility, set the machine to boot from the SSD and rebooted.

Once the machine was up and running on the SSD satisfactorily, I copied all of the virtual machines except one back to the old 750GB hard drive. The VM that I use most, I copied to the SSD.

Then I installed this script onto my machine...

Disable or sleep secondary hard drive in Macbook

and now I can dismount, and spin down the old hard drive when I am not using it. Here's the new configuration...

17" Macbook Pro Late 2011 (MacBookPro8,3 (17")) 256GB San Disk Ultra Plus Sata 6 SSD mounted in hard drive slot Existing 750GB 7200 RPM hard drive moved to optical bay

OS, software and main VM is on SSD. 750GB hard drive is used for VM storage utilization. Spinning disk can be dismounted and spun down on demand, saving battery.

damned cool machine!

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You should be able to just copy over the files from one disk to another, as the Apple boot loader looks for a file named /System/Library/CoreServices/boot.efi on your HFS+ volumes.

So, you just should format your new SSD using Disk Utility, making sure it has the GUID Partition Table scheme (under options in the Partition tab of Disk Utility), then copy over the files from one volume to the other using the Terminal Disk Utility from Lion Recovery. Either way, I would recommend installing Lion Recovery on your new SSD before copying over your old OS.

You can do the copy from a current OS X install, but not the one you're copying from (since a running OS constantly modifies files, therefore risking corrupting the copy) or using the Terminal Disk Utility from Lion Recovery.

Note: I didn't test this myself. But you could definitely try: since it's a copy, you don't risk anything. As always, a proper backup would prevent you from mistakes.

More information on the boot process on Intel Macs can be found here.

Edit: After Manuel's response, and checking with small disk images on a backup drive, it seems that Disk Utility is filesystem-aware, which allows it to copy files from larger volumes to smaller ones, provided that the contents fit the smaller drive.

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Make USB service disk (1GB) and clone disks.

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How do you make a service disk? Could you expand more? – Simon Sheehan Feb 17 '12 at 0:20

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