huge file (2.8GB) wrong size under Knoppix3.7 but ok with XP

[Ralph.Bremer]

Hello,

i burned a bzip compressed image of a Partition to
a DVD+RW with K3B under Knoppix 3.7-2004-12-08
When i mount the DVD+RW under this knoppix i get a very small file size ...

under windos-xp the file has the right size
when i copy it to disk with XP and later
from knoppix do a compare with the original file
with diff -s ... diff tells the files are identical ...
when importing the dvd in a 'new' dvd-project k3b tells the original size 2.8GB ...

to me it seems as if the cdrom filesystem of knoppix makes the mistake with the size ...

however there is a knoppix on DVD and the cloop-file of knoppix can be huge also ...
i dont have that dvd-version of knoppix but the existence of such a version means
there is some way to make k3b burn it different or to mount it different so such a
huge file will be acessible by knoppix without errors ...

anyone knows what is going wrong ?
anyone knows until which file size anything will work without error ?
anyone knows a mount-option to correct the error ?
( the disk is tested to be ok for win-xp as i explained above ... )

i post the exact listings of the file-size i made so anyone can try it out ...

Properties of file on DVD under WIN-XP
image_hda1_mit_programmen.bz
2,83 GB (3.050.302.709 Bytes)
Donnerstag, 31. März 2005, 15:03:06


ll -l of DVD under Knoppix3.7

-r-xr-xr-x 1 root root 13626613 2005-03-31 15:03 image_hda1_mit_programmen.bz


ll -l of original file bevore it was burned wit K3B on the DVD

-rw-r--r-- 1 root root 3050302709 2005-03-31 15:03 image_hda1_mit_programmen.bz


Ralph Bremer

[Harry Kuhman]

...however there is a knoppix on DVD and the cloop-file of knoppix can be huge also ....

No, this is not correct. The Knoppix DVD uses the ISO9660 file system and it does not have files over 2 gig on it. No ISO file system does, it's a limitation of ISO9660. You can write a larger file to a DVD (as was done in your example) if you use a file system other than ISO9660. The common system used on DVDs to do this is UDF. There is a technique that allows one to lie down both ISO and UDF file systems on a DVD (or a CD). This is commonly done to improve compatability of the disc created, since it can be read by either file system. But you do not want to do this if you have files over 2 gig in size, you need to stick with a UDF disc without the ISO "bridge". Or split your large file into several smaller parts under 2 gig each (this is what many DVDs do and why there are many VOB files on a DVD, each under 2 gig in size).

[Ralph.Bremer]

[quote="Harry Kuhman"]
You can write a larger file to a DVD (as was done in your example) if you use a file system other than ISO9660.
The common system used on DVDs to do this is UDF.
There is a technique that allows one to lie down both ISO and UDF file systems on a DVD (or a CD).

Hello,
Thank you verry much !

After Reading your post i tryed to mount my DVD+RW with option -t udf because i was thinking there must be
some udf on it because windows was knowing everything about the file and acessing it correctly ....
the mount did not work because mount complained about beeing unable ....

Now i burned it again wit K3B but unmarking joliet/rockRidge and marking UDF ....
there is no way to disable iso9660 ...
( and man mkisofs tells udf is experimental and therefore iso cant be disabled )
now i can mount the dvd with -t udf and thereafter ls -l tells the right size and
a diff tells the file is identical

however as the unsucessfull try to mount with udf shows the first 'burn' was without udf
and so windows has some magic trick to know about the bigger file size witout udf ....

cold it be the joliet part tells windows about it ?
is it possible to tell knoppix to use joliet extensions instead of rock-ridge when mounting iso9660 ?

Ralph Bremer