document updated 15 years ago, on Oct 29, 2008

When using 'grldr' as a no-emulation CD booter, there is one important caveat:

Your CD-creator MUST be able to create a Rock Ridge CD. i.e. it's probably based on mkisofs.

You can tell you have this problem if grldr is unable to find menu.lst. At the GRUB command prompt, 'cat (cd)/menu.lst' will fail, while 'cat (cd)/MENU.LST' will succeed.

Explanation

The documentation has this obscure note:

Note 6: The iso9660 filesystem driver has Rock-Ridge extension support, but has no Joliet extension support. So you may encounter failure when you attempt to read files on a Joliet CD.

The reason that this is important, is that GRUB needs to read /menu.lst, and it must be in lowercase. However, standard ISO 9660 only supports upper-case. The typical way to get lowercase filenames is Joliet, however, GRUB4DOS doesn't support that.

CD burner support:

Software	no-emulation?	Rock Ridge?
Windows
ImgBurn	yes	no
CDBurnerXP Pro	yes	no
Nero	yes	no?
Linux
...	...	...

Workarounds

TODO: It may be possible to tell 'grldr' to load 'MENU.LST' instead of 'menu.lst'. grubinst.exe --boot-file is able to change it (though it accomplishes this by binary patching the grldr.mbr — search for "patch" in grubinst.c).
Use ISOLINUX. It runs from pure ISO9660, and looks for uppercase "ISOLINUX.CFG".