Installing 10.6.8 on an external HD

You will need to find a Mac you can use that will boot from a Snow Leopard DVD. The version on the DVD is 10.6.3. You will need a 16 GB USB flash drive that is partitioned GUID and formatted Mac OS Extended, Journaled.

The rest of this is done using the computer that can boot a Snow Leopard DVD.

Drive Preparation and Installation

1. Boot from the Snow Leopard Installer Disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu.

2. After DU loads select the USB flash drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.

3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed.

4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.

5. Set the format type to Mac OS Extended (Journaled.) Click on the Security button, check the button for Zero Data and click on OK to return to the Erase window.

6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.

7. After formatting is complete quit DU and return to the installer. Install Snow Leopard being careful to select the USB flash drive as the target (the installer defaults to your startup volume.)

8. Boot the computer using the USB flash drive to test that it works.

9. Download and install the Mac OS X 10.6.8 Update Combo v1.1 update to bring the Snow Leopard system to 10.6.8.

10. Again boot the computer using the USB flash drive to test that it works.

You can now use the USB flash drive to boot your computer. Then clone the USB flash drive system to the external drive you wish to use on your computer. Put the flash drive safely away in case you have to use it again.

Install it there normally and update it to 10.6.8. If your computer shipped with Lion, you'll need to do that on another Mac.

If trying to boot the Mac from that drive produces a blank screen and three beeps, that OS is too old and the only remaining solution is to run Mac OS X Server 10.6 in emulation.

(66794)

Drive Preparation

1. Open Disk Utility in your Utilities folder.

2. After DU loads select your external hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.

3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed.

4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.

5. Set the format type to Mac OS Extended (Journaled.) Click on the Security button, check the button for Zero Data and click on OK to return to the Erase window.

6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.

7. After formatting is complete quit DU and return to the installer. Install Snow Leopard being sure to select the external drive as the target.

Note that you will need a Snow Leopard DVD. The above will only work for you if you can boot your computer from a Snow Leopard DVD. If you have a new model that came with Lion pre-installed then the above will not work because a Snow Leopard retail DVD cannot boot your model.

No, except for the Mac OS X Server note above.

(66795)

Snow Leopard (and Rosetta) running inside Parallels 7 in Lion:

Full installation instructions here:

http://forums.macrumors.com/showthread.php?t=1365439

If she is running 10.6.8 and you have a big enough external drive you could just clone her drive to yours. Create a new admin user account on the clone for you to use. Log into the new account and delete her account.

Clone using Restore Option of Disk Utility

1. Open Disk Utility from the Utilities folder.
2. Select the destination volume from the left side list.
3. Click on the Restore tab in the DU main window.
4. Check the box labeled Erase destination.
5. Select the destination volume from the left side list and drag it to the Destination entry field.
6. Select the source volume from the left side list and drag it to the Source entry field.
7. Double-check you got it right, then click on the Restore button.

Destination means your external disk drive. Source means her internal startup drive.

If she isn't running 10.6.8, then update your clone on her machine or update her machine before you make the clone.

Sure. Once you are running in your own account you can configure it for your computer.

Lefkows wrote:

My iMac came with Lion 10.7.3 installed. That is why I was posing this question.

Kappy: iMacs sold by Apple with Lion pre-installed have firmware that will allow it to boot from Snow Leopard?

They should be able to run 10.6.6 or later unless Apple has put in new ROMs that prevent that. I'm not aware that's the case.