PmWiki | Notes / Grub2

Grub 2 Wiki

Changing default startup item

    > cd /boot/grub2
    > vi grubenv grub.cfg /etc/default/grub

In grub.cfg, lookup the menuentry you want. eg:

    menuentry 'openSUSE' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-0789d7d6-3741-4788-a2b2-f3610829fbc6' {
    ...
    }       
    submenu 'Advanced options for openSUSE' $menuentry_id_option 'gnulinux-advanced-0789d7d6-3741-4788-a2b2-f3610829fbc6' {
        menuentry 'openSUSE, with Linux 3.16.7-24-desktop' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.16.7-24-desktop-advanced-0789d7d6-3741-4788-a2b2-f3610829fbc6' {
        ...

In grubenv, set the following values

    saved_entry=0
    next_entry=Advanced options for openSUSE>openSUSE, with Linux 3.16.7-24-desktop

where saved_entry is the index of the top level item, here 'openSUSE'
next_entry is the menuentry of the item in the submenu you want.
Note the '>' in between!!!!!

You need to do it like this, because there is no way of selecting the next_entry in '/etc/default/grub'

NOTE:

GRUB_HIDDEN_TIMEOUT and such do not appear to work at all, possibly because Lenovo has its own way of handling UEFI boot loaders.
In the Lenovo boot menu, you can only select the top level boot item ('openSUSE' above), not the exact submenu item underneath it.