#66 mkudffs doesn't clear all the previous info

[Anonymous]

Found a small problem with mkudffs, as obtained from
udftools-1.0.0b3-7.fc6.

The problem is as follows: if I take a new DVD-RAM
disk and create (say) an ext3 filesystem, and some
time later I run mkudffs over it, then when I try
to mount it the disk still seems to remember about
having had a previous filesystem.
What I mean is that mount may succeed if one
specifies the newer filesystem, at least if no
files have been copied yet, and also succeed with
the older filesystem.

Here is an example, for the same disk(!) without
any formatting nor copying in between (note also
the dates)

# mount /dev/scd0 /mnt/dvd -t udf
# ll /mnt/dvd/
total 4
drwxr-xr-x 3 root root 92 2007-11-21 18:34 ./
drwxr-xr-x 13 root root 4096 2007-09-03 17:27 ../
drwxr-xr-x 2 root root 40 2007-11-21 18:34 lost+found/

# umount /mnt/dvd
# mount /dev/scd0 /mnt/dvd -t ext3
# ll /mnt/dvd/
total 24
drwxr-xr-x 3 root root 4096 2007-11-21 19:29 ./
drwxr-xr-x 13 root root 4096 2007-09-03 17:27 ../
drwx------ 2 root root 16384 2007-11-21 19:29 lost+found/

Eventually I found that I could erase the (or at
least part of the) information that remained from
ext3 by using fdisk to set a filesystem of type "0"
("empty") and then running mkudffs over.

That is not very practical of course, and I am also
not completely sure that no other outdated info
remains on the disk.

[Nobody/Anonymous]

Logged In: NO

I found that blanking the first MB of the disk before calling mkudffs:

head --bytes=1000000 > /dev/scd0