[WBEL-users] Creating ISO images from CDs

[Chris Audley]

Sounds like a block size issue, try using a specific blocksize.  Doing a
little quick math, it looks like the LCD on the ISO images is 32K, so
try

Dd if=/dev/cdrom of=image.iso bs=32768

See if that gives you any better results.  The only reason this matters
is to get the MD5 checksums to match.  The little extra padding that
gets added to the end of the image because of the large blocksize does
not negatively impact the integrity of the generated CD.

Cheers
Chris 

-----Original Message-----
From: Alfred von Campe [mailto:alfred@110.net] 
Sent: Friday, November 05, 2004 9:09 AM
To: Chris Audley
Cc: whitebox-users@beau.org
Subject: Re: [WBEL-users] Creating ISO images from CDs

> You can use dd to make a copy of your ISO images off of the CD's.
>
> dd if=/dev/cdrom of=image.iso
>
> When you are done, verify the md5sum against the checksums posted on 
> the whitebox site to make sure you got a good copy.

I used the dd command to create new ISO images (and I also found the ISO
images sitting on a co-worker's computer).  But their size was slightly
larger than the original ISOs, so of course the MD5 sums didn't match:

-rw-r--r--  1 alfred  staff  657719296  4 Nov 17:39
liberation-respin1-binary-i386-1.iso
-rw-r--r--  1 alfred  staff  662110208  4 Nov 17:58
liberation-respin1-binary-i386-2.iso
-rw-r--r--  1 alfred  staff  498499584  4 Nov 18:11
liberation-respin1-binary-i386-3.iso
-rw-r--r--  1 alfred  staff  658026496  4 Nov 14:31 wbel3-1.iso
-rw-r--r--  1 alfred  staff  662417408  4 Nov 14:33 wbel3-2.iso
-rw-r--r--  1 alfred  staff  498806784  4 Nov 14:35 wbel3-3.iso

However, I copied all these ISO images to my Mac, mounted the images,
and then did a "diff -r", and there was no difference found on any of
the three disks.  Can anyone explain how this is possible?

Alfred