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View Full Version : Unable to boot from image - am I doing this right?


ThaboWoof
03-09-2006, 02:31 PM
I've been browsing the threads but still have not come across what may be causing my firewire drive to not be recognized on boot up. I just wanted to clarify that what I was doing was indeed the correct procedure.

My hardware is newish a Powerbook with a 300 gig seagate drive in a Hardbox - sarotech enclosure (- Oxford chipset I think FW 400/800 and USB2.0) I have the trial version of SuperDuper! (will buy when I can figure out this problem :)) Tigger 10.4.5 with latest updates etc. My external drive is partitioned with one 100gig and one 200 gig partition and both have the little checkboxes "ignore owership of this volume turned off" and its not journaled.

Here is what I've been doing:

1) Fire up SuperDuper! and select my laptop HD as source for "Copy" and for the "to" option I select a "Disk Image" (Read/Write sparse Image) and make the location on the 100 gig partition of my firewire drive.

2) I select "Backup - all files", "Before copy repair permissions", "During copy erase ....." and under the advanced tab nothing is checked.

3) Hit ok and it all works fine (after about 2 hours - I have a 100gig laptop drive) The image on the firewire drive is mountable and I can browse the files in the image.

4) I unmount the image and reboot the computer while holding down the option key. The bios (or whatever apple calls it) pops up and I see a little icon for my laptop hard drive but nothing for my external firewire??? (Doing an appel-i on the partition reveals when it was connected as just an external show me that it is bootable.)


So my qustions are:

A)Is the above the correct method to back up to an external firewire drive ( I realize that with the paid version once I have the image I can just add to it and not have to wait the 2 hours each time)

B)Why is my drive not regognized as being bootable by the laptop?


Thanks
Richard

dnanian
03-09-2006, 02:34 PM
Richard --

An image isn't a physical drive, and thus can't be booted from. If you want to be able to boot from the drive, you need to write directly to it.

Once you do that, given what you've said, it should boot just fine.

ThaboWoof
03-09-2006, 03:05 PM
I had an idea that it was something simple like that - thanks!

What would the point be of making am image then? A pal informed me that I could booting from the OS X DVD on start up and select the image like that for a restore.

So in summary then if I want to make the copy of my laptop's drive bootable I need to select the actual external drive as the source not "image" in the "to" pull-down option. Now if I want to say restore this copy how will I able to do so without having an image ?? My primary goal is to just have a copy of my laptop's hard drive not boot from firewire and use that copy (that was more of a test rather than what I'll be doing on a day to day basis) More questions ...... sorry for my confusion :confused: Should I be making an image like I have been doing or just copy all the data to the external drive as described in your fix?

Regards
Richard

dnanian
03-09-2006, 04:29 PM
An image retains its bootable properties, Richard... it just can't be booted from until restored to a real drive. And, yes -- as we describe in our User's Guide, you can boot from the OSX DVD and use that to restore. Once restored to a real drive, it'll boot (as long as it's a real "Backup - all files" maintained with Smart Update or Erase, then copy).

So, if you want to make a copy bootable, yes, you'd choose the volume/partition as the destination. And if you want to restore it, you'd either use Disk Utility from the OSX DVD (which can copy volume-to-volume) or you'd boot from it and use SD! to copy back. I go into this in detail in the User's Guide.

Hope that helps!

jblundell
03-17-2006, 03:14 PM
This puzzled me for a while too, and the technical descriptions of the differences made little sense until finally I had one of those "aha" moments.

Any given volume can only be the boot drive for a particular system. What if you have several systems? Because an image is not bootable, then you could store many images on a single volume, giving you the possibility to fully restore any system from its unique image. If the volume were bootable, then it would be dedicated (for boot purposes at least) to only the system used to make the bootable copy. Of course, there is no reason not to put images from other systems on the bootable volume, after all, they are only data files.

I think I begin to understand it now, but someone please correct me (or delete this post!) if I'm off base.

dnanian
03-17-2006, 03:36 PM
Actually, on the Mac, a given volume can usually act as the boot (start up) volume for many different Macs (of course, only one at a time). It's one of the cool things about the Macintosh and OSX.

But -- an "image" isn't a physical drive. It's a file, on a drive, that represents a volume -- but isn't "real", and thus can't be booted from.

When you restore the "image", you "expand" it from a single file to a whole set of files and folders on a physical drive. At that point, it's "real" -- and thus can act as a startup disk.

It's kind of like files in a Stuffit or ZIP archive vs. files on your drive. You have to "unstuff" (restore) the image to a real drive before you can use it.

Make more sense?

jblundell
03-17-2006, 08:44 PM
I'm playing with that right now. Moved an external hard drive with a bootable Intel (Core Duo) iMac backup and used it to boot an Intel (Core Solo) Mini Mac. It boots fine and I can do everything except see the Options page on the Display System Preferences. The Mini Mac had it (and you need it to turn off Overscan) but its just not there on the iMac backup. Looks as though it is something that Apple put in the Mini version of OS X but not the iMac version.

Anyway, it sure is impressive!

dnanian
03-18-2006, 01:38 AM
It's quite possible (and likely) that the Mini has a later version of OSX than the iMac does. That happens all the time...