[Fedora-livecd-list] Allowing livecd images large than 4GiB

[Bruno Wolff III]

On Tue, Dec 16, 2008 at 12:57:22 -0500,
  Bryan J Smith <bjs at redhat.com> wrote:
> 
> Well, then I'd say you tested it.  You're sure the filesystem is UDF
> Plain, correct?  It wasn't ISO 9660 Yellow Book (possibly as a result of
> UDF not being accepted as an option for some reason)?

I am not sure how to tell. I changed things so the initscript was going to
mount it using a fs type of udf. On the test before I changed the drivers
and the fs type the mount failed.

> I've actually never dissected the ISO files I regularly create with
> mkisofs.  But I know I've gone beyond 4.0GiB (~4.3GB) before, so they
> must be Level 3.

The livecd-creator process barfs in the squashfs file system is over
4 GIB compressed. The mkisofs documentation says this should happen
at 2 GiB. So I am not entirely sure what gives there.

> We're kinda spoiled on Linux, because an .iso file != as written, but
> the kernel hides a lot of that in the block access.  An .iso file, last
> time I checked, is ISO 9660 "Yellow Book" (data) track.  So I'm curious
> if an .iso file, as well as written to optical media, is still a single
> track for > 4.0GiB (> ~4.3GB), or multiple Yellow Book tracks with the
> extent in the first. 

I suspect it was one track, but I don't know for sure. I used k3b and the
burn iso dvd tool.

> Depends.  I was under the impression that when not using PC BIOS floppy
> emulation, but native mode with El Torito, it uses still requires and
> accesses the ISO 9660 Yellow Track, which needs to have filenames
> limited to 31 characters.

But there aren't many files visible at that level. A few things in the
equivalent of /boot and the rest is the file containing the squashfs
file system.