Can't startup from fresh clone - at a loss
 

Darndest thing.

I just did the simplest backup clone of my Leopard 10.5.2 startup drive. All seemed to have gone well, but after selecting the new Startup disk in System Preferences, though it’s highlighted, I’m returned to the original.

The chosen disk, a SAMSUNG HD753LJ, a second internal is formatted HFS+ Journaled.
The computer is a Mac Pro Early 2008.
DiskWarrior OKed it just a couple hours before making the backup.
The original, according to Cmnd + I, is 49.77 GB, whereas the clone is 49.77 GB. The partition to which the copy was made is 200 GB.
The computer was restarted holding down the Shift key before beginning.

Choosing the cloned system after holding down the Option key, returned me to the original disk.
So I thought I’d simply re-do the “Backup - all files” procedure, but found the partition now grayed out.

What’s the remedy? Where do I begin?

You're running from the backup: you can't judge from the position of the drive on the desktop. Look in the "About this Mac" panel.

Good Gravy.

Sure'nuff, I AM started up from the clone!

This clone was made for two purposes:
1. assuring I'll have a working system, should the 10.5.4 go wrong
2. to preserve the kagillion apps which take forever to locate and install

Once all proves to be working well off the clone, I plan to use that SD! clone as the primary startup, the actual everyday working System and disk. The original 300MB disk which came with the computer will be partitioned, with one of those partitions, twice the size of the OS and apps, to be used for a clone of the clone, as the final emergency backup.

My backup strategies developed over years and years, aren't really convertible to whole-scale backups, either with SuperDuper, Time Machine, or anything else. Different partitions are designated their particular functions and file types -- the old dog and new tricks thing applies.

Thanks for always spot-on help, Mr. Nanian.

Glad I could help.