Cannot Boot from external drive..

[iambeetle]

I do backup regularly and few days ago, my internal hard drive failed.
So I got the hard drive replaced and installed a new operation system.

I tried to boot from my backup disk, however, I couldn't see it on my Startup disk option. I thought it was the problem with USB drive. So I put my backup disk into a Firewire enclosure.

This time, I can see the backup disk from the Startup disk option. I choosed to start up from the disk. However, my Powerbook G4 got frozen with a grey screen without a apple logo on it.

Any guess what is wrong with it?

Thanks a lot!!

[dnanian]

That seems weird -- no, I don't know what might be wrong. But, if you have a clean drive, during the first boot, please indicate that you want to copy files from an old Mac. Then, point that to the backup on the FireWire drive, and it should migrate your applications and data.

[iambeetle]

I have solve the problem with a little help from my other mac...

This is what I did...
I connect my powerbook G4 to a macbook by firewire, the powerbook is set to taget disk mode. And connect my macbook to the external hard drive.
Then I use superduper to copy all files from the external ahrd drive to my powerbook. It works fine.

But I am wondering what is wrong with my external hard drive?
It's not bootable as mentioned but if I clone the drive to my powerbook, it's fully functional.... Is it the problem of the formating of my external drive?

Is there any specific requirement for a external bootable drive?

If I can solve this, maybe restoring my data will be easier... thanks a lot!

[dnanian]

It's not so much the formatted (it's Mac OS Extended if you were able to write directly to it), but possible the partitioning (which, for a Power PC Mac, needs to be "Apple Partition Map"). It's also possible that your drive isn't boot compatible with Mac OS X...

[rdmeyers]

Is there a list of OS X "boot compatible" drives somewhere? I want to buy a LaCie d2 quadra to use as a boot drive. Does anyone know if this is compatible?

[dnanian]

You know, there really isn't. The Quadra should work, though, although it might not boot as eSATA.

[rdmeyers]

OK,
You also noted that the ext drive has to be an Apple Partition Map to be bootable. Does this mean if you have a dual boot MBP using boot camp it may not work because of the partitioning of the internal drive?

[dnanian]

An external drive only has to be Apple Partition Map if it's a Power PC Mac. For Intel, use GUID.

[rdmeyers]

I just finished my first back-up with my registered version of SD. I tried to boot from the ext drive but the system went gray and hung after selecting the WD Mybook FW800 drive as the boot drive. I saw your last post about using GUID and I'm a bit confused.
I used OS X extended for the format type when preparing the drive and I'm guessing that really does not matter because SD erases and formats it anyway...
I check the Partition type on the ext drive using drive utility and it is Apple_HFS.

Is it possible it won't boot because it is divided into two partitions by boot camp?

By the way thanks for all the help and if you want me to move this to a different thread let me know.

[dnanian]

Try changing the partition scheme to "GUID" for your Intel Mac...

[rdmeyers]

Yep that works. I re-copied the disk out after changing the scheme to GUID. Now if I could just have the option to boot to either of the Operating Systems that are on the original disk I would be real happy.

Thanks for the help