Boot SnowLeopard Mac w/Leopard clone?

[geiswood]

Hi,
My 24" iMac running Leopard is in the shop w/hard drive failure. I have an SD clone of this iMac/leopard on an external hard drive. I "restored" this clone to a new G-tech drive using SuperDuper, so now I have 2 clones. This way I do not harm the first clone.

I thought I could use clone2 to boot a 27" iMac running Snow Leopard but no luck so far. I don't want to restore my clone to it; I just want to use the clone.

The clone is seen in the startup manager and I can select it. I do get the Apple logo, but nothing else happens.

Thinking I did not do enough in formatting the G-tech drive, I erased it, made sure everything was GUID, partitioned it. RE-restored the clone to it. Tried to boot the Snow Leopard 27" iMac. Still no luck.

Why is this not booting the machine? Ideas?

[dnanian]

Sounds to me like the Snow Leopard Mac doesn't support Leopard... it needs Snow Leopard to run, since that's what supports the hardware.

[geiswood]

Rats. That what I thought.

And I was just reading another of your answers, from 2008, that said basically the same thing. So, thanks for the reply. I wish that answer had changed!

http://www.shirt-pocket.com/forums/s...ead.php?t=4560

The problem is that you're trying to boot a Mac from a version of OSX that doesn't support it. In general, you cannot start up a 'new' mac from a version of OSX that was released before the Mac was.

OSX is great because a given version of OSX is 'universally' compatible with Macs that were released at the time of the OSX version. But new Macs often come with new chips, display devices, etc that are not recognized or supported by earlier version of OSX.

You can fix this by doing a Leopard upgrade to the backup, although that might not be what you want to do... you can also start up from your Leopard install and access your files on the backup (but not run from it).
__________________
--Dave Nanian

[sjk]

Thanks for digging up that 2008 post, geiswood. It's one of those timeless info-gems, always worthy of a reminder.

[dnanian]

Definitely - that's why the I've got a new Mac, should I SuperDuper! to it? FAQ is there, too... to try to capture this issue.

[kapalama]

Experimentation has shown me that HFS+ partitions on APM, GPT, and MBR disks all boot Intel macs.

Experimentation has also shown me that a partition's ability to actually boot has little to do with the ability of the Startup Disk system preference panel's ability to choose it as the boot disk. Usually Startup Disk will allow you to choose any actual bootable partition, but often it will let you choose partitions that cannot actually boot your Mac. For instance I can choose a PPC partition from my Intel Macs Startup Disk prefs, but it will not actually boot my Mac.

[dnanian]

Whether they *can* boot an Intel Mac doesn't mean they're supported in that capacity. Apple's been pretty explicit in what they want used here, and it's GPT/GUID (which are the only ones that can be selected in the Startup Disk Preference Pane).

And, yes - the pane will allow you to select a drive that won't start your Mac, but not one that isn't bootable for *something*.

[ajsedl]

I've been using SuperDuper! for years as my backup methodology, from my main computer (a MacBook Pro) to a LaCie hard drive. It's always worked fine and still does, allows me to boot from either.

BUT--and here's the problem: My only computer, my MacBook Pro had to go in for repairs. They replaced both the optical drive and the logic board. While I was without it (10 days), I tried to use my husband's newer MacBook Pro to boot from my backup on the LaCie drive. It goes into the gray apple mode but then nothing. Doesn't boot. ALL these are running system 10.6.6. What stops the boot from my husband's computer?

Now I learn they have to re-replace the logic board because they put in the wrong processor (they gave me a downgrade in GHz in the first repair!) I need to know how to boot from the LaCie with his MacBook before my one-and-only computer goes away! Thanks for any help.

[dnanian]

Because your husband's new MacBook Pro has a special build of 10.6.6 (and 10.6.7) and can't run from the older/different OS. Hopefully things will become "universal" again when/if 10.6.8 is released.