[CentOS-devel] Net Install ISO

Wed Oct 10 12:33:45 UTC 2012
James Pearson <james-p at moving-picture.com>

Chandana De Silva wrote:
> Hello All,
> 
> I need to create a slightly modified Centos 6.3 Net Install ISO. The 
> modification is trivial, (a default kickstart in isolinux.cfg). I have 
> created a new ISO by loopback mounting the original, copying to a new 
> directory, editing and using mkisofs, and it works as expected.
> 
> This is how I made the new ISO:
> 
> <code>
> cd my_install_directory
> sudo mkisofs -o ~/centos63-ks.iso -b isolinux/isolinux.bin -c 
> isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -R -J 
> -v -T  .
> </code>
> 
> However, I an unable to copy this new ISO into a USB disk using dd, in 
> the same manner as the original net install iso. I believe this is 
> because the new ISO does not include an MBR. How do I include an MBR in 
> the new ISO, so that it can be transferred to a USB disk via DD, in the 
> same way as the original ?

I believe you need to run 'isohybrid' on the new ISO - e.g. in your case:

  isohybrid ~/centos63-ks.iso

isohybrid is part of the syslinux package

Also, you might want to run "hardlink" on your 'my_install_directory' 
before running mkisofs - this will make the resulting ISO image a bit 
smaller

James Pearson