Carbon Copy Cloning question.

Question

Hi all.
Today I made a CCC (exact clone) of my hard drive to an external HD via a USB connection. I wanted a bootable backup of everything. To achieve this end one of the requirements in the setup process was the need to erase the target volume.
This I did. But when the job was done I received the following message:
"The target volume will not boot powerPC Macs. PowerPC Macs can only boot from a hard drive that is partitioned with the Apple Partition Map format".
So what does that mean, and what do I have to do to comply with this requirement? Obviously erasing the target HD does not do the trick.
Regards

Answer 1

Janset wrote:
What I find strange, why does the error message not say exactly what the problem is instead of using criptic messages.
The message seems cryptic because you have interpreted it as an error message when it actually is an informational message, one that warns you about a restriction on the kind of +partition scheme+ required to boot a PowerPC-based Mac.
A partition scheme is not the same as a +file system+. A partition scheme defines how a drive is portioned into sections for different purposes. A file system defines how one or more of those sections, called partitions, is organized into files. "Apple Partition Map" (APM) is an example of a partition scheme. "Mac OS Extended" (HFS Plus or HFS+) is an example of a file system.
Partition schemes are associated with hardware & firmware items that control the beginning stages of the boot process, before a full-fledged operating system is loaded from a file system. It is called "booting the system" because of the analogy to "pulling yourself up by your own bootstraps" -- it seems paradoxical because the OS can't load its files if it isn't already loaded from them. All modern Macs (& most PC's) depend on a sort of "mini OS" embedded in the firmware to overcome this, either +Open Firmware+ ("OF") for PPC-based Macs or +Extensible Firmware Interface+ ("EFI") for Intel-based ones.
Neither firmware-based mini OS is sophisticated enough to read the contents of file systems directly; instead it reads data from a predefined location on the drive, defined by the partition scheme, which in turn tells it how to load the next part of the boot sequence, which eventually leads to the components of an OS being loaded that can read from & write to the file systems it supports.
Thus, it is not sufficient that the boot partition be formatted as "Mac OS Extended (Journaled)" for the OS that it contains to boot a PPC-based Mac. If it is part of the wrong partition scheme, the OF will never find it. Similarly, because the built-in OF doesn't explicitly support booting from USB-connected drives, it is unsupported by Apple & may generate a similar informational message.