restoring an image

  • Thread starter Thread starter Jan Janssen
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J

Jan Janssen

Hello!
I have problems in understanding something about images.
I am always told that an image is a replica of a volume on cluster level.
So restoring a complete volume from an image file restores the original
cluster structure. I understand that.
But what if I do a partial restore, (say just 1 file) from an image?
The original cluster can be filled in the meantime with complete different
stuff, which would become destroyed by the partial restore.
So must I assume that complete restore is on cluster level and partial
restore is not? Can hardly believe that. Or is an image not on cluster
level?
Somebody can perhaps give me more insight?
Jan
 
File restore from an image is done on the file level. The file will be
restored to available space.

An image restore is "supposed to" restore everything to their original
segments/clusters. In actuality, this does not always occur. I have found
that Ghost 9.0 does. TrueImage 8.0 does not!

If you do a boot time defrag with PerfectDisk 7 and then follow up with a
regular defrag with PerfectDisk 7, the disk is optimized and clean. Now
create an image with TrueImage 8. Then restore the image. You will see that
the disk geometry is different if you immediately runs an analysis from
within PerfectDisk 7. You have to run another boot time defrag to get it
back to where it initially was - prior to creating the image.

Not so with Ghost 9. Everything goes back as it was!

I have done a rather extensive test on these two imaging programs. I will
e-mail a copy in either .doc or .pdf format if you, or anyone else, would
like to see it.

Remove the obvious from my e-mail address to contact me.


--
Regards,

Richard Urban

aka Crusty (-: Old B@stard :-)

If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!
 
File restore from an image is done on the file level. The file will be
restored to available space.

An image restore is "supposed to" restore everything to their original
segments/clusters. In actuality, this does not always occur. I have found
that Ghost 9.0 does. TrueImage 8.0 does not!

If you do a boot time defrag with PerfectDisk 7 and then follow up with a
regular defrag with PerfectDisk 7, the disk is optimized and clean. Now
create an image with TrueImage 8. Then restore the image. You will see that
the disk geometry is different if you immediately runs an analysis from
within PerfectDisk 7. You have to run another boot time defrag to get it
back to where it initially was - prior to creating the image.

Not so with Ghost 9. Everything goes back as it was!

I have done a rather extensive test on these two imaging programs. I will
e-mail a copy in either .doc or .pdf format if you, or anyone else, would
like to see it.

Remove the obvious from my e-mail address to contact me.


--
Regards,

Richard Urban

aka Crusty (-: Old B@stard :-)
Click to expand...
Richard,
This is a perfect answer on my question, thank you very much!
I asked you already by email about your experiments.
Rgds,
Jan
 
Your assumptions are wrong because you don't understand the difference.

With Ghost 9, a file or multiple file restoration (partial restoration)
restores the original files to the existing EMPTY clusters and stores this
cluster location information in the FAT. This is copying a file with
translation of the contents of the image file. This is like when you copy a
file from one source to another with windows explorer. Files are copied to
vacant, unused clusters. The FAT is checked first for files already stored
and their locations, thus their cluster locations first. If this was not
done, files would be overwritten all the time. A partial image restore,
windows explorer, application installation or whatever.

So, I don't see how any damage can occur in this process.

Ghost 9 uses sector by sector copying, thus it knows at full image file
restoration, the contents of the partition copied, the FAT contents, the
cluster size, and the contents of each and every cluster. The restoration
occurs on vacant space on the hard drive, nothing can be damaged either.

Read up on cylinders, heads, and sectors (CHS) on hard drives. Then
partition construction, File allocation tables (FAT), formatting, and
related cluster sizes. Then, how files are stored in a FAT. Widely found
with Google.
 
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