TIP_Add_custom_stages_to_a_gentoo_cd

Add custom stages or other files to a gentoo CD iso image

Intro

This is a quick and easy way to customize a livecd to contain your preferred stages, without going through the hassle of creating a completly new filesystem. This is not what you need if you want to change the way the gentoo install/livecd works. But it is handy to store stages or other files you may need for the install.

Begin

1. Grab an iso image from gentoo.org, I recommend a minimal cd image for maximum free space.

2. Create some directories

  $ cd /mnt/
  $ mkdir oldimage
  $ mkdir newimage

3. mount your gentoo cdrom iso image to /mnt/oldimage

  $ mount -o loop /home/user/install-x86-minimal-2006.0.iso /mnt/oldimage

alternative: mount a previously burned CD

3.1 troubleshooting loop setup:

enable loopback support in kernel
modprobe loop // if loop was compiled as a module

mount should handle all the dirty work for you if the kernel is setup right. 

But if you need or want to get your hands dirty use the losetup command (part of sys-apps/util-linux).
for example, to free (unmount) the first loop device: losetup -d /dev/loop/0 
to see which loop devices are in use: losetup -a

4. Extract the CD contents into a temporary directory

  $ cp -a oldimage/* newimage

5. Add a directory to store things in, and fill it:

 
  $ mkdir newimage/stages
  $ cp ~/stage4.tar.bz2 newimage/stages/

Create iso

6. Now you are ready to create a new iso image using mkisofs:

  $ cd newimage
  $ mkisofs -J -R -l -V "My 2006.0 livecd" -o /mnt/mycd.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table ./

7. Check the resulting image to ensure it fits on your media:

ls -lh /mnt/mycd.iso 
-rw-r--r--  1 root root 134M Apr  6 03:30 /mnt/mycd.iso

  $ qemu -cdrom /mnt/mycd.iso -boot d -m 128

8. Burn mycd.iso to a cd using your favorite cd burning application.

9. Clean up

  $ cd /mnt
  $ umount /mnt/oldimage
  $ rm -r oldimage newimage
  $ mv mycd.iso ~/