Very Computer

Can anyone tell me how to make an _identical_ backup of
a cd-rom?

Is something along the lines of

#dd if=/dev/scd1 of=/tmp/cdimage.raw bs=1024k count=1
#cdrecord -speed=4 dev=0,0,0 /tmp/cdimage.raw

going to get me anywhere?

On Tue, 18 Jul 2000 10:08:59 +0200, Simon [Working with T. Cooper]

Nope.  The block size is wrong there, and the "count" is severely wrong.
You'll get I/O errors out the wazoo.  The "readcd" utility that comes
with recent cdrecord releases is supposed to do the right thing, but I
never got it to work.  I've done it like so:
mount /cdrom
df
Filesystem           1k-blocks      Used Available Use% Mounted on
/dev/hdc                476504    476504         0 100% /cdrom
Now divide that "476504" number by 2, giving 238252.  Then just
dd if=/dev/cdrom of=/tmp/cdimage.raw bs=2k count=238252

The bs=2k is there because data sectors on a CD-ROM are supposed to be
2048 bytes in size.  You can actually leave the "count=" off, but you'll
get I/O errors when dd tries to read past the end of the CD, and you may
have to manually Ctrl-C to stop dd.  Either way, when dd is finished,
just do the cdrecord command with a blank CD-R(W) in the drive.

This will not work with audio CDs, naturally--use cdparanoia for that...

--
Matt G|There is no Darkness in eternity/But only Light too dim for us to see
If the chances are a million to one against something happening, the
odds are 50/50 that it will.  Especially if that something is a bad
thing.

On Tue, 18 Jul 2000 10:08:59 +0200,

Quote:>Can anyone tell me how to make an _identical_ backup of
>a cd-rom?

>Is something along the lines of

>#dd if=/dev/scd1 of=/tmp/cdimage.raw bs=1024k count=1

leave of the count=1, or you will only get one block, not the whole
cd. Really, the bs=1024k isn't need either. so that's simply:

dd if=/dev/scd1 of=/tmp/cdimage.raw

Quote:>#cdrecord -speed=4 dev=0,0,0 /tmp/cdimage.raw

Thats:

cdrecord -speed=4 dev=0,0,0 -data /tmp/cdimage.raw

Quote:>going to get me anywhere?

Yes, you've got the idea.

Perry