Your shiny new CLFS system is almost complete. One of the last things to do is to ensure that the system can be properly booted. The instructions below apply only to NewWorld Macintoshes.
Boot loading can be a complex area, so a few cautionary words are in order. Be familiar with the current boot loader and any other operating systems present on the hard drive(s) that need to be bootable. Make sure that an emergency CD is ready to “rescue” the computer if it becomes un-bootable. It is also a good idea to enable booting from Open Firmware in case things go really wrong.
Earlier, we compiled and installed the yaboot boot loader software in preparation for this step. The procedure involves writing the bootloader to a bootstrap partition and blessing it so that Open Firmware will boot from it. This is all handled by ybin, the yaboot installer.
Ybin writes an optional 'OS selector' menu into Open Firmware, then
writes yaboot and yaboot.conf
to the
bootstrap partition, blesses this, and updates the boot device
recorded in nvram. When booted, the OF provides the initial menu to
choose between linux, boot from CD, and e.g. OSX (depending on what
was in yaboot.conf
). If you boot to
'linux', yaboot is executed and lets you select which kernel to use.
Images (kernels) are specified, together with any necessary path, in
yaboot.conf
- the details are
incorporated into the bootloader, but no attempt is made to access or
validate the paths until they are selected. There are many possible
options that can be specified in yaboot.conf
, see the man page for the details. Most
people will be able to specify device=hd: (for a single hard disk),
but if you have multiple disks, or if you wish to be pedantic, you
can specify the full OF path to the device, obtained by running
ofpath /dev/hdX .
Using the above information, determine the appropriate designators
for the bootstrap partition and the root partition. For the following
example, it is assumed that the bootstrap partition is hda2
and the root partition is hda7
. We will also assume that you wish to be able
to boot an OSX installation on hda4
.
Change these items as necessary for your machine.
If your machine has a SATA disk, specify the partitions using
/dev/sda7
and so forth in the usual
way. At least some of the distros specify a full OF path to the
'device' and to the image(s), such as device=/ht@0,f2000000/pci@3/k2-sata-root@c/k2-sata@0/disk@0:
for the disk, and image=/ht@0,f2000000/pci@3/k2-sata-root@c/k2-sata@0/disk@0:9,/boot/clfskernel-3.10.14
which definitely works.
Create a “yaboot.conf” file defining yaboot's boot menu:
cat > /etc/yaboot.conf << "EOF"
# Begin /etc/yaboot.conf
# By default, yaboot will boot the first menu entry.
# Allow 10 seconds before booting the default.
# this will also apply to the first-stage os selector
timeout=100
# These variables are global
# first, where to put the bootstrap partition
boot=/dev/hda2
# Which disk to use
device=hd:
# Default partition for the kernel images
partition=7
# default root partition
root=/dev/hda7
# where ybin is to find yaboot and ofboot
install=/usr/lib/yaboot/yaboot
magicboot=/usr/lib/yaboot/ofboot
# allow the initial menu to offer CD as an option
enablecdboot
# allow the initial menu to offer booting from Open Firmware
enableofboot
# allow the initial menu to boot from mac osx
macosx=/dev/hda4
# white on black is boring!
# note the spellings : 'fgcolor' but 'light'
# in this context, light means 'without high intensity'
fgcolor=light-green
# The first entry is for CLFS.
# For all images, the pathname is relative to the filesystem
# on which they are situated and can include at most one
# directory
image=/boot/clfskernel-3.10.14
label=2.1.0
read-only
EOF
Add an entry for the host distribution, if you have one. It might
look something like this if the kernel and initrd are in the host's
'/' directory on hda6
:
cat >> /etc/yaboot.conf << "EOF"
title Debian
image=/pci@f4000000/ata-6d/disk@0:6,/vmlinux
label=Debian
initrd=/pci@f4000000/ata-6d/disk@0:6,/initrd.gz
initrd-size=10000
append="root=/dev/hda7"
read-only
EOF
The following command will update the bootstrap partition and the boot variable in Open Firmware. Do not run the command if this is not desired.
ybin
Alternatively, if the bootstrap partition has not already been initialized, perhaps because you are using a Live CD, you will need to use a different command to install the bootloader for the first time:
mkofboot