How to create a FreeBSD 8.0 boot CD without boot.flp?

Manolis Kiagias sonicy at
Wed Feb 10 22:07:16 UTC 2010

On 10/02/2010 11:56 μ.μ., Pierre-Luc Drouin wrote:
> I just realized that cdboot does not contain the kernel as boot.flp
> used to, so I guess /boot/kernel has to be there... So it does not
> seem to work with mkisofs. I did
> mkisofs -J -R -no-emul-boot -b ./cdboot -iso-level 3 -V FreeBSD_Custom
> -o custom_FreeBSD_8_0_i386_cd.iso custom_FreeBSD_8_0_i386_cd
> and it throws:
> mkisofs: Uh oh, I cant find the boot image './cdboot'
> I tried with the absolute path for cdboot and it does not help either.
> From the mkisofs man page it says that -no-emul-boot has to be added
> if the size of the image file is not 1200, 1440, or 2880 kB. I noticed
> that the cdboot file is only 1.2 kB, so I guess -no-emul-boot is
> required... Do you have an idea what could be wrong?
> Thanks!

No need to specify an absolute path - the path you are using for the
files is used. Here is another example:

Assuming your files are in my_cd_files (and there is a boot/cdboot
directory structure in there):

mkisofs -J -R -no-emul-boot -b boot/cdboot -iso-level 3 -V
FreeBSD_Custom -o custom-freebsd.iso  my_cd_files

or you could even do:

cd my_cd_files

mkisofs -J -R -no-emul-boot -b boot/cdboot -iso-level 3 -V
FreeBSD_Custom -o ../custom-freebsd.iso  .

(note the dot at the end)

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