[Qemu-devel] Re: Boot Failure (CDROM boot failure code : 0004)

[Volkan YAZICI]

On Mon, 16 Jun 2008, Anthony Liguori <address@hidden> writes:
> Volkan YAZICI wrote:
>>   root:~# dd bs=$[1024 * 32] \
>>   > if=/dev/scd0 \
>>   > of=/root/windows-server-2003-standard-x86-64-sp2.iso
>>   
>
> Your dd line is very suspect.  Why are you using a block size of 32k?
> The sector size of most CD-ROMs is 2k.  I've certainly encountered my
> fair share of CD-ROMS that were an odd multiple of 2k.  dd will
> silently truncate the ISO if the size is not a multiple of 32k.

You seem to be right. See below command outputs.

  windows:~$ md5sum windows-server-2003-standard-x86-64-sp2.iso \
  > >windows-server-2003-standard-x86-64-sp2.iso.md5sum

  root:~# dd bs=2048 if=/dev/scd0 of=/root/scd0.iso
  root:~# md5sum scd0.iso >scd0.iso.md5sum

  root:~# diff \
  > /root/scd0.iso.md5sum
  > /home/windows/windows-server-2003-standard-x86-64-sp2.iso.md5sum
  1c1
  < b5d670b7360dc43af8157a50de43bac1  scd0.iso
  ---
  > cfcf3b24d9b44e75826259c9e914bf40  
windows-server-2003-standard-x86-64-sp2.iso

  root:~# ls -lb \
  > /home/windows/windows-server-2003-standard-x86-64-sp2.iso \
  > /root/scd0.iso
  -rw-r--r-- 1 windows windows 4840085504 2008-06-13 17:54 
/home/windows/windows-server-2003-standard-x86-64-sp2.iso
  -rw-r--r-- 1 root    root    4840085504 2008-06-17 08:54 /root/scd0.iso

But trying to start qemu with the scd0.iso didn't make any
difference. Should I try with a different bs value?


Regards.