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Bless me Father, for I have sinned...

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... I have committed great atrocities against Mac OSX....

Based on the info at about blessing folders to make them bootable, I found that it was necessary to do a little bit more.

# bless --info "/Volumes/FW1"
finderinfo[0]: 187 => Blessed System Folder is /Volumes/FW1/System/Library/CoreServices
finderinfo[1]: 746345 => Blessed System File is /Volumes/FW1/System/Library/CoreServices/boot.efi
finderinfo[2]: 0 => Open-folder linked list empty
finderinfo[3]: 0 => No OS 9 + X blessed 9 folder
finderinfo[4]: 0 => Unused field unset
finderinfo[5]: 187 => OS X blessed folder is /Volumes/FW1/System/Library/CoreServices


The relevant information in this case is that the blessed system folder is at inode 116, and that path (for the human reader) is /System/Library/CoreServices. PowerPC-based Macs need only this piece of information to boot. PPC Open Firmware will find that directory, then execute the file named "BootX" within that directory. Intel-based Macs also use the "Blessed System File" information. In this case, that is the file at inode 546345 and (again, for the human reader), that file is located at /System/Library/CoreServices/boot.efi.

If you ever need to bless a volume manually (for example, if CCC indicated that it was unable to bless the volume), you could run this command in the Terminal application:

sudo bless -folder "/Volumes/Backup/System/Library/CoreServices"

It is important to note that blessing a volume is different than specifying a boot device. Blessing a volume simply updates the information in the HFS Volume Header that indicates where the blessed system folder and file are located. When you specify a particular volume as the startup disk, on the other hand, the computer stores a reference to that volume in the "Non volatile RAM" -- basically a small section of RAM whose contents are not lost when the machine loses power or is shutdown. The importance of this disctinction, and all four of these rules for that matter, is that simply setting a volume as the startup disk may not be sufficient to actually boot from that volume.

In my particular case, executing the above "bless" resulted in a single folder that was blessed, so FW1B, the backup/rsync copy of FW1, wasn't blessed the same. Turns out the fix is simple, thanks to the man page for bless:

sudo bless -folder "/Volumes/FW1B/System/Library/CoreServices" -file "/Volumes/FW1B/System/Library/CoreServices/boot.efi"

And that's how you make it bootable. This is Mac OSX 10.6.7, I think.

The long story made short is that I wound up with two system images on a single hard drive, one of which could *not* be shrunk below 145GB, despite having 40GB of free space. It appears that limit is due to another partition on the same drive not being 145G+145G away from the original image. Once both images are shrunk, the 105GB images will fit on a single 320GB drive, giving me back my 1TB drive.

This link was used to form the basis of that rsync. I used the built-in rsync from /usr/bin/rsync, rather than another product.

The basic process was:

1) Blank disk
2) Partition disk
3) rsync from original disk partition #1 to target disk partition #1
4) rsync from original disk partition #2 to target disk partition #2
5) bless files & folders on target disk partition #1 to match blessed folders on original disk partition #1.
6) test booting from target disk partition #1.

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