On 2023-10-19, Dale <rdalek1...@gmail.com> wrote:
> That config kinda reminds me of the old grub. A title line, location of
> kernel and then options. Sounds easy enough. The new grub config is
> almost impossible to config by hand. They had to make a tool to do it.
> That says a lot there. ;-)
Manually configuring Grub2 for a single OS is pretty trivial. Here's
a typical grub.cfg file:
-----------------------------grub.cfg------------------------------------
timeout=10
default=0
root (hd0,0)
menuentry vmlinuz-5.15.135-gentoo {
linux /boot/vmlinuz-5.15.135-gentoo root=/dev/sda1
}
menuentry vmlinuz-5.10.76-gentoo-r1 {
linux /boot/vmlinuz-5.10.76-gentoo-r1 root=/dev/sda1
}
------------------------------------------------------------------------
If you want to get fancy and use labels and UUIDs, it looks like this
------------------------------grub.cfg----------------------------------
search --no-floppy --label ROOT --set root
timeout=10
default=0
menuentry vmlinuz-5.15.135-gentoo {
linux /boot/vmlinuz-5.15.135-gentoo
root=PARTUUID=fd96ac2d-5521-c043-9fdb-5067b48fb063
}
menuentry vmlinuz-5.15.127-gentoo {
linux /boot/vmlinuz-5.15.127-gentoo
root=PARTUUID=fd96ac2d-5521-c043-9fdb-5067b48fb063
}
------------------------------------------------------------------------
Most distros add 2 or 3 layers of obsfucation on top of grub.cfg with
scripts upon scripts upon scripts that read a dozen or so config files
and automagically detect kernels and initrds and other OSes and then
generate a grub.cfg file containing many hundreds of lines of stuff.
If you just boot one OS with a "main" kernel and a "backup" kernel,
then all you need is what you see above.
