How do I check if an ISO burned correctly?

[ToddAndMargo]

Hi All,

When I burn an ISO with cdrecord:

cdrecord -v driveropts=burnfree -data dev=$CD $NewIso

How do I verify the burn went correctly?

I have tried using md5sum on the ISO and on the
raw device (/dev/scd0), but no joy. The sums
are always different, even when I can verify
that the disk is good, such as the checker on
a Linux install disk.

K3B gets away with this, but I have no idea way.
(My ISO md5sum is the same as K3B's).

AAHHHHHHHHHHH!!!

Any advice would be greatly appreciated!

Many thanks,
-T

[Tatome]

ToddAndMargo wrote:
> Hi All,
>
> When I burn an ISO with cdrecord:
>
> cdrecord -v driveropts=burnfree -data dev=$CD $NewIso
>
> How do I verify the burn went correctly?

Well, I'm not sure - there might be apps out there doing exactly what
you want. But you could just go ahead and do
| diff -s $NewIso $CD

Cheers,
Johannes

[ray]

I believe there are some nulls added to fill out a block at the end of the
CD. The trick is to end the checksum before it gets there. I've seen the
solution, but don't recall where.

[Mark Hobley]

ToddAndMargo <ToddAn...@nospam.verizon.net> wrote:
> How do I verify the burn went correctly?

Have a look at my notes. My files burn and checksum ok. Remember you need to
burn "disk at once" to get a valid checksum.

http://markhobley.yi.org:8000/CDR

If you are using pad options, you may also wish to look at my notes on
checksumming DVDR media:

http://markhobley.yi.org:8000/DVDRcrc

Regards,

Mark.

--
Mark Hobley
393 Quinton Road West
QUINTON
Birmingham
B32 1QE

Email: markhobley at hotpop dot donottypethisbit com

http://markhobley.yi.org/

[Sam]

ToddAndMargo writes:

> Hi All,
>
> When I burn an ISO with cdrecord:
>
> cdrecord -v driveropts=burnfree -data dev=$CD $NewIso
>
> How do I verify the burn went correctly?

Mount the disk, then:

find $MOUNTPOINT -type f -print | xargs cat >/dev/null

That's going to reread everything on the CD, if this completes without
reporting any errors, you're good to go.

[Bit Twister]

On Sat, 24 Nov 2007 06:39:37 GMT, ToddAndMargo wrote:
> Hi All,
>
> When I burn an ISO with cdrecord:
>
> cdrecord -v driveropts=burnfree -data dev=$CD $NewIso
>
> How do I verify the burn went correctly?
>
> I have tried using md5sum on the ISO and on the
> raw device (/dev/scd0), but no joy. The sums
> are always different, even when I can verify
> that the disk is good, such as the checker on
> a Linux install disk.

I use this script to get md5sum or pull cd back to disk run md5sum.

-------------- script starts below this line -------------------
#!/bin/sh
#**************************************************************
#*
#* rawread_cd - read cd in the raw mode.
#*
#* Usage: rawread_cd /dev/cdrom
#*
#* Install: chmod +x rawread_cd
#*
#* See http://www.troubleshooters.com/linux/coasterless.htm
#* for original scrip and cd tips
#*
#*
#* When making an ISO from an existing factory created CD,
#* create and verify the ISO against the CD using the rawread_cd script.
#*
#* rawread_cd /dev/cdrom | md5sum
#* or
#* rawread_cd /dev/cdrom > myiso.iso
#* md5sum myiso.iso
#*
#* Mandrake users may have to down load something like
#* mkisofs-2.0-6.i386.rpm from http://www.rpmfind.net
#* or one of the mirrors to get the isoinfo utility.
#* Mandraklinux release 10.X might have in cdrecord-isotools
#* added readcd line from article Message ID: slrnd68v6...@one.localnet
#*
#* Mandriva Releases needs cdrkit, cdrkit-isotools, cdrkit-genisoimage rpms
#*
#**************************************************************

if [ $# -lt 1 ] ; then
tput clear
echo -e "\n $0 Error. Usage:"
echo -e "Example md5sum checks:"
echo -e "\t rawread_cd /dev/cdrom | md5sum"
echo -e "or"
echo -e "\t rawread_cd /dev/cdrom > myiso.iso"
echo -e "\t md5sum myiso.iso \n"
exit 1
fi

device=$1

blocksize=`isoinfo -d -i $device | grep "^Logical block size is:" | cut -d " " -f 5`
if test "$blocksize" = ""; then
echo catdevice FATAL ERROR: Blank blocksize >&2
exit 1
fi

blockcount=`isoinfo -d -i $device | grep "^Volume size is:" | cut -d " " -f 4`
if test "$blockcount" = ""; then
echo catdevice FATAL ERROR: Blank blockcount >&2
exit 1
fi

command="dd if=$device bs=$blocksize count=$blockcount conv=notrunc,noerror"
command="readcd -v dev=$device f=- sectors=0-$blockcount"
echo "$command" >&2
$command

#************************* end rawread_cd *************************************

[ToddAndMargo]

ToddAndMargo wrote:
> Hi All,
>
> When I burn an ISO with cdrecord:
>
> cdrecord -v driveropts=burnfree -data dev=$CD $NewIso
>
> How do I verify the burn went correctly?

Hi Tatome, Ray, Mark, Sam, Bit,

Thank you all so much!

-T