Subject: Re: [LeapList]Backing up CD's
To: Ray <email@example.com>
From: Brian Rose <firstname.lastname@example.org>
Date: 07/23/2003 14:45:33
I tried using dd's skip and seek arguments, both failed. Apparantly it opens the device and still reads the first 821 blocks and discards them. Here's the command I used...
dd if=/dev/cd0a of=Comanche4.iso bs=2k seek=821
dd: /dev/cd0a: Input/output error
821+0 records in
821+0 records out
1681408 bytes transferred in 2.623 secs (641024 bytes/sec)
I also tried resuming at other blocks and I found that they peppered the CD with bad blocks.
822 - 0 blocks read
823 - 14 blocks read
837 - 0 blocks read
838 - 19 blocks read
857 - 0 blocks read
858 - 2 blocks read
This hardly seems to be a practical method. Also, what do you replace the bad blocks with?
Perhaps I can create a new dd argument that will ignore I/O errors. Time to hit the source.
> On Wed, 23 Jul 2003, Brian Rose wrote:
>>I've used this on other CDs without issue. But on this game CD I get the following...
>>bash-2.05b# dd if=/dev/cd0a of=Comanche4.iso bs=2k ; ls -la
>>dd: /dev/cd0a: Input/output error
>>821+0 records in
>>821+0 records out
>>1681408 bytes transferred in 2.174 secs (773416 bytes/sec)
> try having dd skip 1681408 bytes and resume the imaging process. Once
> complete, cat the second image into the first.