FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Ubuntu > Ubuntu User

 
 
LinkBack Thread Tools
 
Old 08-13-2008, 06:47 AM
andy baxter
 
Default weird dvd burning issue

hello,

I have just encountered a weird issue when trying to burn an iso image
of a data dvd. I used k3b to do the burn, at 2x speed to an external usb
dvd burner. In k3b, the verification phase of the burn failed. Also,
when I md5sum /dev/scd0 it returns a different sum from md5summing the
iso image.

However, when I did:

root@monkey:~# diff -qr /mnt /media/cdrom0 | tee iso.diff

there was no output and iso.diff was empty, so there is no difference in
the files on the dvd. I then tried copying /dev/scd0 back to the hard
disk using:

root@monkey:~# dd if=/dev/scd0 of=/home/andy/Desktop/64studio-from-disk.iso
1633856+0 records in
1633856+0 records out
836534272 bytes (837 MB) copied, 107.058 s, 7.8 MB/s

When I list the two files together, the one copied back from the dvd is
slightly longer than the original iso:

root@monkey:~# ls -l /home/andy/Desktop/64*
-rw-r--r-- 1 andy andy 836503552 2008-08-13 02:40
/home/andy/Desktop/64studio_2.1_i386.iso
-rw-r--r-- 1 root root 836534272 2008-08-13 07:38
/home/andy/Desktop/64studio-from-disk.iso

('64studio-from-disk.iso' is the one copied back by me; the other is the
original).

Does anyone know what is going on here, and whether this is a known
issue? My dvd drive reports itself as a 'freecom optical disk drive' in
lsusb.

andy

--
ubuntu-users mailing list
ubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-users
 
Old 08-13-2008, 07:53 AM
andy baxter
 
Default weird dvd burning issue

andy baxter wrote:
> hello,
>
> I have just encountered a weird issue when trying to burn an iso image
> of a data dvd. I used k3b to do the burn, at 2x speed to an external usb
> dvd burner. In k3b, the verification phase of the burn failed. Also,
> when I md5sum /dev/scd0 it returns a different sum from md5summing the
> iso image.
>
> However, when I did:
>
> root@monkey:~# diff -qr /mnt /media/cdrom0 | tee iso.diff
>
> there was no output and iso.diff was empty, so there is no difference in
> the files on the dvd. I then tried copying /dev/scd0 back to the hard
> disk using:
>
> root@monkey:~# dd if=/dev/scd0 of=/home/andy/Desktop/64studio-from-disk.iso
> 1633856+0 records in
> 1633856+0 records out
> 836534272 bytes (837 MB) copied, 107.058 s, 7.8 MB/s
>
> When I list the two files together, the one copied back from the dvd is
> slightly longer than the original iso:
>
> root@monkey:~# ls -l /home/andy/Desktop/64*
> -rw-r--r-- 1 andy andy 836503552 2008-08-13 02:40
> /home/andy/Desktop/64studio_2.1_i386.iso
> -rw-r--r-- 1 root root 836534272 2008-08-13 07:38
> /home/andy/Desktop/64studio-from-disk.iso
>
> ('64studio-from-disk.iso' is the one copied back by me; the other is the
> original).
>
> Does anyone know what is going on here, and whether this is a known
> issue? My dvd drive reports itself as a 'freecom optical disk drive' in
> lsusb.
>
> andy
>
>
P.S. I have just successfully installed from the iso, so the difference
is obviously not in the iso's boot sector.

andy

--
ubuntu-users mailing list
ubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-users
 
Old 08-13-2008, 05:14 PM
Rashkae
 
Default weird dvd burning issue

Reply *way* below

andy baxter wrote:
> hello,
>
> I have just encountered a weird issue when trying to burn an iso image
> of a data dvd. I used k3b to do the burn, at 2x speed to an external usb
> dvd burner. In k3b, the verification phase of the burn failed. Also,
> when I md5sum /dev/scd0 it returns a different sum from md5summing the
> iso image.
>
> However, when I did:
>
> root@monkey:~# diff -qr /mnt /media/cdrom0 | tee iso.diff
>
> there was no output and iso.diff was empty, so there is no difference in
> the files on the dvd. I then tried copying /dev/scd0 back to the hard
> disk using:
>
> root@monkey:~# dd if=/dev/scd0 of=/home/andy/Desktop/64studio-from-disk.iso
> 1633856+0 records in
> 1633856+0 records out
> 836534272 bytes (837 MB) copied, 107.058 s, 7.8 MB/s
>
> When I list the two files together, the one copied back from the dvd is
> slightly longer than the original iso:
>
> root@monkey:~# ls -l /home/andy/Desktop/64*
> -rw-r--r-- 1 andy andy 836503552 2008-08-13 02:40
> /home/andy/Desktop/64studio_2.1_i386.iso
> -rw-r--r-- 1 root root 836534272 2008-08-13 07:38
> /home/andy/Desktop/64studio-from-disk.iso
>
> ('64studio-from-disk.iso' is the one copied back by me; the other is the
> original).
>
> Does anyone know what is going on here, and whether this is a known
> issue? My dvd drive reports itself as a 'freecom optical disk drive' in
> lsusb.
>

I'm afraid I don't know why k3b verification is failing..

With regards to the other issues, this is normal. dd will always read
past the end of the image and grab some null bytes on DVD's.

You need to use isoinfo program to determine the correct size of the iso
for dd to copy.

Example:

isoinfo -d -i /dev/scd0

The output will include:

Logical block size is: 2048
Volume size is: 2089612


Then you plug those into dd (the 2048 should be a constant, I think)

dd if=/dev/scd0 bs=2048 count=2089612 of=sample.iso (or pipe it into md5sum


--
ubuntu-users mailing list
ubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-users
 

Thread Tools




All times are GMT. The time now is 02:06 AM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org