[gentoo-user] Re: Exact setting in grub to default to a kernel by name?

[Grant Edwards <grant.b.edwards@gmail.com>]

On 2021-06-14, Walter Dnes <waltdnes@waltdnes.org> wrote:

> On Mon, Jun 14, 2021 at 01:00:38AM -0000, Grant Edwards wrote

>> All my grub.cfg files looks like this:
>> 
>> ========================================================================
>> timeout=10
>> root=hd0,1
>> default=0
>> 
>> menuentry 'vmlinuz-5.10.27-gentoo' {
>>   linux /boot/vmlinuz-5.10.27-gentoo root=/dev/sda1
>>   }
>>  
>> menuentry 'vmlinuz-5.4.97-gentoo' {
>>   linux /boot/vmlinuz-5.4.97-gentoo root=/dev/sda1
>>   }
>> ========================================================================
>
>   Thanks.  It's nice to have a working example.  Are you booting via
> BIOS?  I'm on a UEFI-only machine, and the generated grub.cfg has...

The example above is BIOS boot with a GPT labelled root disk.

Now that you've reminded me, I do have one UEFI system, and it does
contain a few extra global lines. It's also GPT labelled, and still
contains the original Lenovo Win10 installation -- I shrunk the Win10
partition and added two new partitions (Linux root, Linux
swap). Below is the grub.cfg for that machine:

IIRC, it worked fine without any of the gfx/font/video stuff, but like
you I wanted a nice big font.

Note that on this machine I just tell grub to search for the
filesystem with the label "root" instead of specifying it manually --
though it is still specified manually for the kernel argument. I don't
remember why I did that...


========================================================================
timeout=5

loadfont "DejavuSansMono24"
set gfxmode=auto
set gfxpayload=keep
insmod all_video
insmod gfxterm
terminal_output gfxterm

search --set=root --label rootfs

sleep 2

menuentry vmlinuz-5.10.27-gentoo {
  linux /boot/vmlinuz-5.10.27-gentoo root=/dev/nvme0n1p5
}

menuentry 'vmlinuz-5.4.97-gentoo' {
  linux /boot/vmlinuz-5.4.97-gentoo root=/dev/nvme0n1p5
}

menuentry 'vmlinuz-4.19.175-gentoo' {
  linux /boot/vmlinuz-4.19.175-gentoo root=/dev/nvme0n1p5
}
========================================================================