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Rad Community Technical Discussion Boards (Computer Hardware + PC Software) >> Cloning Programs (Except Norton Ghost) >> An Image Is An Image
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Message started by Pleonasm on Oct 4th, 2007 at 6:57am

Title: An Image Is An Image
Post by Pleonasm on Oct 4th, 2007 at 6:57am
A backup image should be, literally, a true cluster-for-cluster duplicate of the source volume.  This criterion is considerably more strict than simply stating that the image contains all of the files from the source volume, because it implies not only that the “image has everything” but also that “everything is in its proper place.”

Interestingly, I can find no instances of a user actually testing this property of a backup image.  To do so, therefore, I employed a simple approach:  mount an image as a drive (using ShadowProtect Desktop 3.0) in Windows, use WinHex 14.4 to retrieve the LCNs (Logical Cluster Numbers) for a file from the mounted image, and compare that to the LCNs of the same file residing on the source volume.  A test of a set of files shows that the file location is captured and represented in the image just as it exists on the source volume.

While this test didn’t compare the LCNs of every file on the image to the source volume, it does demonstrate that (indeed!) “an image is an image” — i.e., the image contains not only the contents of the source volume, but also its layout as well.

P.S.:  Using WinHex to view a mounted image is a quite intriguing technique that to the best of my knowledge has not been reported elsewhere.  In addition to exploring the LCNs of files on the mounted image, you can also examine the Master Boot Record (or any other sector(s)), etc.

Title: Re: An Image Is An Image
Post by TheShadow on Oct 13th, 2007 at 11:22am
An Image is an Image?
Duh, wat dat mean? :-/

When I make an Image of my HD with Ghost 2003 or 8.3, and compress it, it's like a huge ZIP file.  The programs are in the order in which Ghost put them in the file, not the way they are arranged on the HD.  It reads Folder +files, Folder + files till it reaches the end of data, just like reading them in Windows Explorer.

When restoring, it does not put the data in the same spot on the HD where it found it.  It lays the data down in the order in which it was read.
That's why I use a Ghost restore to implement a total 100% defrag and HD compaction.

I can create a Ghost Image file of my HD, even though there may be fragmentation and lots of holes in the data pattern, and when I do the Restore, it looks like this:



A clone, on the other hand would be an exact mirror image of the original HD.

Cheers Mates!
The Shadow  8-)


Title: Re: An Image Is An Image
Post by Pleonasm on Oct 13th, 2007 at 3:44pm
The Shadow, your post highlights the fact that Ghost 2003/8.3 doesn't produce an image backup, strictly speaking (at least when configured with its typical, default settings).  An image is a one-to-one "reflection" or "photograph" of the source, and this is what Ghost 9/10/12 and ShadowProtect, for example, produce; whereas, what Ghost 2003/8.3 delivers is an "archive".  There is no functional difference between the two, of course; and each has a few unique advantages that the other lacks (e.g., ability to mount an image versus the defragmentation benefit of an archive).

Please consider my initial post simply as an exploration into a topic that had not been previously investigated.

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