On 10/02/2010 04:03 AM, Gregory Woodbury wrote: > > > On Sat, Oct 2, 2010 at 4:40 AM, Andre Robatino > <robatino@xxxxxxxxxxxxxxxxx <mailto:robatino@xxxxxxxxxxxxxxxxx>> wrote: > > JD <jd1008 <at> gmail.com <http://gmail.com>> writes: > > > I burned Fedora-14-Beta-i386-DVD.iso to blank dvd. > > One time I used wodim, and 2nd time I used growisofs. > > After each burn, I would dd the dvd back in: > > > > dd if=/dev/sr0 of=f14.iso bs=2k > > > > In both cases the size of f14.iso was 10240 bytes larger than > > Fedora-14-Beta-i386-DVD.iso. > > In general this won't work unless dd is told exactly how much to > read off. > Unfortunately, it works often enough that people think it's > supposed to. Use the > rawread script from > > http://www.troubleshooters.com/linux/coasterless.htm#rawread > > instead. This determines the ISO size from the ISO header and then > automatically > reads off the right amount. > > There is a defect in the Live and netinst images (which started in > F12 Alpha, > and only affected i386 and x86_64, not ppc), in that they are > larger than the > ISO header indicates: > > https://bugzilla.redhat.com/show_bug.cgi?id=585006 > > To read these off properly, the rawread script won't work, since > it assumes that > the ISO header size is correct. Instead, you have to manually > compose a dd > command that reads off the size corresponding to the actual ISO > file (not the > size in the ISO header). > > > One can also tell dd to read by single physical layer sectors using > the "bs=2048" > option. This may increase the read time a bit, but generally results > in s more consistent > chance of getting the correct size. > > -- > G.Wolfe Woodbury > So, what block size do you think I am using in my command: >> dd if=/dev/sr0 of=f14.iso bs=2k It has no effect. As Andre states, the correct size is in the in the header info. The actual physical size on the DVD seems to have been padded by 10240 bytes (not sure if that is done during dvd burn, or during dvd read), and the script Andre pointed me (us) to does the right thing. Thanx again, Andre! -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
