On Tue, 2007-05-08 at 02:37 -0400, Andre Robatino wrote: > When I burned the Fedora ISOs to CDs, I used cdrecord with padding to > avoid the readahead bug - see > > http://www.troubleshooters.com/linux/coasterless.htm > > for how. In short, you use something like > > cdrecord -v dev=/dev/cdrom -dao -pad padsize=63s FC-6-i386-disc1.iso > > It turns out that the same precaution is necessary with DVDs, and until > recently I was able to use cdrecord for this, like > > cdrecord -v dev=/dev/dvd -dao -pad padsize=63s FC-6-i386-DVD.iso > > even though a lot of ugly-looking error messages appeared before the > burn commenced. But in the last month or so, instead of burning, > cdrecord simply gives up. See > > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=233745 > > I know about growisofs, but unfortunately it's incapable of putting > padding on the DVD _after_ the ISO file (I know it has a -pad option, > but it just passes it through to mkisofs, which provides padding > _inside_ the ISO, which isn't what is needed, and when burning an ISO > file it can't be used anyway). I tried once using dd to manually add > zero padding after the ISO, but although the resulting DVD passed > mediacheck, it failed to boot properly. So it seems that at the moment > there's no tool that can reliably burn a DVD and pad it properly. After > gradually learning over several years how to reliably burn Fedora ISOs, > I don't want to go back to mediacheck hell. As I see it, there are > several options: > > 1) Fix the readahead bug. Unfortunately, we all know that will never > happen. No one who's qualified cares enough to do it. > > 2) Fix cdrecord. The last time I successfully used it was March 29, so > some update since then broke it. It's not the kernel, since after > booting into the same kernel I was using then, it was still broken. > > 3) Find some other tool besides cdrecord that can do the necessary > padding for DVDs. Are there any? > > 4) Modify mediacheck. I know that by default mkisofs provides enough > padding to protect the files inside the ISO from the readahead bug. But > mediacheck is apparently checking the entire ISO, including the padded > part at the end after the actual files in it, where the readahead bug > occurs. Can it be tweaked to just check up to the end of the last file > inside the ISO? And can something similar be done so no errors occur > during the actual install either? All of my FC DVDs have been written with: growisofs -dvd-compat -Z /dev/dvd=/path/to/dvd.iso with nary a glitch (no need for read ahead padding, nada). Burned on multiple machines with different DVD writers, readers, etc. Either I've been hugely lucky or you've been hugely unlucky. ---------------------------------------------------------------------- - Rick Stevens, Principal Engineer rstevens@xxxxxxxxxxxx - - VitalStream, Inc. http://www.vitalstream.com - - - - To iterate is human, to recurse, divine. - ----------------------------------------------------------------------
