Re: Setting GRUB 2 default menu entry

[Jordan Uggla]

On Sun, Jan 27, 2013 at 11:52 PM, Francesco Turco <address@hidden> wrote:
> Hello.
>
> I'm running GRUB 2.00 on a Gentoo Linux system.
>
> I compile my own kernels manually, and then I install them in /boot with
> make install. I have the following kernels in /boot at the moment:
>
> # ls -1 /boot/vmlinuz*
> /boot/vmlinuz-3.7.4-gentoo-5
> /boot/vmlinuz-3.7.4-gentoo-first
> /boot/vmlinuz-3.7.4-gentoo-fourth
> /boot/vmlinuz-3.7.4-gentoo-third
>
> Running grub2-mkconfig results in the following output:
>
> # grub2-mkconfig -o /boot/grub2/grub.cfg
> Generating grub.cfg ...
> Found linux image: /boot/vmlinuz-3.7.4-gentoo-third
> Found linux image: /boot/vmlinuz-3.7.4-gentoo-fourth
> Found linux image: /boot/vmlinuz-3.7.4-gentoo-first
> Found linux image: /boot/vmlinuz-3.7.4-gentoo-5
> done
>
> If I now read the resulting /boot/grub2/grub.cfg file, I notice that the
> following entries have been created:
>
> - A main default entry which starts vmlinuz-3.7.4-gentoo-third
> - A submenu with the all the other entries (including recovery ones), in
> the same order as the grub2-mkconfig command
>
> The problem is that at boot time I'd like to load by default the fifth
> revision of my kernel (vmlinuz-3.7.4-gentoo-5), not the third one
> (vmlinuz-3.7.4-gentoo-third). I also prefer not to access the submenu
> for choosing the right kernel to load.
>
> How can I change this behaviour? How can I tell GRUB that I want to run
> the fifth revision of my kernel by default and not the older third
> revision? In general, how can I change the default entry line to match
> the kernel I want and not a seemingly random one picked by GRUB?
>
> I also tried with setting GRUB_DEFAULT=3 in /etc/default/grub and
> re-running grub2-mkconfig. But at boot time the default entry is still
> vmlinuz-3.7.4-gentoo-third.
>
> Another problem I noticed with the GRUB_DEFAULT approach is that it
> seems that you first have to run grub2-mkconfig for having the orderded
> list of kernels, then you set that variable with the number of kernel
> you want to load by default, but at last you have to re-run
> grub2-mkconfig in order for the variable to take effect.
>
> Thank you.
>
> _______________________________________________
> Help-grub mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/help-grub

Does http://www.gnu.org/software/grub/manual/grub.html#default clarify
things for you? Also, I highly recommend that you use a consistent
naming scheme with your kernel images, and that that scheme use
numbers that aren't spelled out, e.g. "/boot/vmlinuz-3.7.4-gentoo-4"
rather than "/boot/vmlinuz-3.7.4-gentoo-fourth" so that grub-mkconfig
will sort them by largest version number first, as you probably want.

-- 
Jordan Uggla (Jordan_U on irc.freenode.net)