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  • Thread starter Thread starter j2222
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J

j2222

Why does this happen:

Take a drive ~20Gb, format it, restore files to it ... 15 VMWARE machines,
so small number of very large files. And they are immediately
fragmented!!!! If I restore from backup they should be non-fragmented to
start with ... why does this happen??

Thanks,
James
 
I'm not an expert. This has been an issue with restored files since the
earliest of Windows days. It was supposedly fixed on W2K with SP3 but I
haven't had the opportunity to verify that. I just never bothered with
it and just did a defrag after restoration. Search Microsoft Knowledge
Base for "fragmented restored files" and you should get hits on this.

John
 
Jihn,
Thanks for the info ... I'll take a look ... I can't defrag, the files they
are very big and the drive has little free space ... I've tried restoring
1/2 then defraging, but this doesn't seem to help,

James
 
You're welcome. I was a bit lazy earlier today when I replied but I did
remember reading about the problem not too long ago. Anyhow I am now
not so lazy so I found this on the MS KB:

Data Fragmentation Occurs When You Use Ntbackup.exe to Restore Data to a
Clean Volume
http://support.microsoft.com/default.aspx?scid=kb;en-us;297268

Says:

SYMPTOMS
After you restore data from a tape to a clean NTFS file system volume,
many of the restored files may be fragmented on the disk.
CAUSE
This problem occurs because Ntbackup.exe does not give NTFS any
information about how big the file that is being restored is. Because of
this, NTFS must pre-allocate standard size runs of clusters to hold the
file. This means that it typically allocates too much space that is
later returned to the free cluster pool when the file is fully restored.
These small runs are then used again for restoring later files, and this
caused file fragmentation to occur.
STATUS
Microsoft does not plan to resolve this problem in Windows NT 4.0. This
problem was first corrected in Windows 2000 Service Pack 3.

John
 
Hmmm ... thats odd, because I'm restoring from an uptodate 2000 server to an
XP SP2 workstation. Perhaps I'll try copying the data off, then back ...
rather than backup/restore.

James
 
Well, tried ROBOCOPYing data off and back and still heavily fragmented
(20,000 frags in a single file) ... so looks like NTFS is the problem!

James
 
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