Wodim unable to write on DL DVD Drive

[JD]

On 04/03/2013 02:06 PM, Preston Hagar wrote:
> On Tue, Apr 2, 2013 at 7:24 PM, JD <jd1008 at gmail.com 
> <mailto:jd1008 at gmail.com>> wrote:
>
>
>
>     $ /opt/schily/bin/mkisofs -iso-level 3 -print-size dvd.iso
>
>     Setting input-charset to 'UTF-8' from locale.
>     Total extents scheduled to be written = 2391761
>     2391761
>
>     $ /opt/schily/bin/mkisofs -iso-level 4 -print-size dvd.iso
>     Warning: Creating ISO-9660:1999 (version 2) filesystem.
>     Warning: ISO-9660 filenames longer than 31 may cause buffer
>     overflows in the OS.
>
>     Setting input-charset to 'UTF-8' from locale.
>     Total extents scheduled to be written = 2391762
>     2391762
>
>     Why the difference in output?
>
>
>
> My understanding (I'm not an expert on DVDs by any means) is that 
> there was an issue with ISO files larger than 4 GB in early version of 
> cdrtools (mkisofs, cdrecord, etc).  Since DVDS are 4.7 GB (or 4.4 GB 
> or 4.3 GB depending on who you ask and how), the 4 GB limit meant that 
> most DVDs could still be burned.  With dual layer DVD, blu ray, etc, 
> that 4 GB limit gets passed all the time.
>
> Jorg Schilling (the cdrtools guy) wrote a fix for it using ISO-9600 
> muti-extent files, but some versions of the Linux kernel had a bug 
> that meant that his fix wouldn't work.  I think (not sure) that the 
> bug has been fixed in all newish versions of the kernel.  Because of 
> that bug, cdrecord and mkisofs still default to not useing the 
> multi-extent file code since it is more tested and works with more 
> kernels (as long as the file is smaller the 4 GB).  When the file is 
> larger than 4 GB, you have to use the -iso-level flag to make it use 
> the multi-extent file code.
>
>
> Clear as mud right?
>
>
> Here is a little more rom the man page if it helps any:
>
>
> -iso-level level
>               Set the ISO-9660 conformance level. Valid numbers are 
> 1..3 and 4.
>
>               With level 1, files may only consist of one section and 
> filenames are restricted to 8.3 characters.
>
>               With level 2, files may only consist of one section.
>
>               With level 3, no restrictions (other than ISO-9660:1988) 
> do apply.  Starting with this level, mkisofs also allows files to be 
> larger than 4 GB by implementing ISO-9660 multi-extent files.
>
>               With all ISO-9660 levels from 1..3, all filenames are 
> restricted to upper case letters, numbers and the underscore (_). The 
> maximum filename length is  restricted  to  31  characters,  the 
>  directory  nesting  level  is
>               restricted to 8 and the maximum path length is limited 
> to 255 characters.
>
>               Level 4 officially does not exists but mkisofs maps it 
> to ISO-9660:1999 which is ISO-9660 version 2.
>
>               With  level 4, an enhanced volume descriptor with 
> version number and file structure version number set to 2 is emitted. 
>  There may be more than 8 levels of directory nesting, there is no 
> need for a file to contain a dot
>               and the dot has no more special meaning, file names do 
> not have version numbers, the maximum length for files and directory 
> is raised to 207.  If Rock Ridge is used, the maximum ISO-9660 name 
> length is reduced to 197.
>
>               When creating Version 2 images, mkisofs emits an 
> enhanced volume descriptor which looks similar to a primary volume 
> descriptor but is slightly different. Be careful not to use broken 
> software  to  make  ISO-9660  images
>               bootable by assuming a second PVD copy and patching this 
> putative PVD copy into an El Torito VD.
>
>
>
> You might Google a little further on cdrtools, multi-extents and 4GB 
> files.
> Preston
>
Thank you kindly Preston.
That does indeed clear it up.

Cheers,

JD