Grub 2

FACTS

od verze 2.00 se nejak sere…prej /boot neni ext3.. takze instaluju s –force –recheck a pote nutno zamknout soubor core.img (aby se neposunul, jinak se to podela jak lilo…bug)

# chattr +i /boot/grub2/i386-pc/core.img

zmeny do /etc/default/grub

Zmena kernel boot options

https://fedoraproject.org/wiki/GRUB_2#Updating_the_GRUB_configuration_file

do Fedora 33

upravime /etc/default/grub

pregenerujeme vlastni config

# grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

Fedora 33+

Boot options jsou ulozene v grubenv souboru, takze nestaci manualni zmena v /boot/grub2.grub.cfg.

Dale se zmenila cesta ke konfiguracnimu souboru, puvodni je pouze „include“ noveho!

upravime /etc/default/grub

pregenerujeme vlastni config

# grub2-mkconfig -o /boot/grub2/grub.cfg

VYPNUTI OSTATNICH OS [ OS-PROBER ]

edit /etc/default/grub; add lines / modify value:

GRUB_DISABLE_OS_PROBER="true"

vygenerujeme znovu konfiguraci

sudo grub2-mkconfig > /boot/grub2/grub.cfg

Preskoceni systemu z boot menu

do /etc/default/grub pridat

GRUB_OS_PROBER_SKIP_LIST="4E26E10726E0F13F@/dev/sda1 07a6db3e-fed0-1e8e-c1b3-548e3bd90d64@/dev/sda6"

vygenerujeme znovu konfiguraci

sudo grub2-mkconfig > /boot/grub2/grub.cfg

PREINSTALACE Z LIVECD

Plati pro disk /dev/sda kde je Linux nainstalovan na oddilu /dev/sda7.

sudo mount /dev/sda7 /mnt
sudo mount --bind /dev /mnt/dev
sudo mount --bind /dev/pts /mnt/dev/pts
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys /mnt/sys
sudo chroot /mnt
grub-install /dev/sda
update-grub
exit
sudo umount /mnt/{dev/pts,dev,proc,sys}
sudo reboot # restartuje okamzite, nebo restartuj rucne :)

GRAFIKA

[ http://forums.fedoraforum.org/showthread.php?t=276691 ]

vypsani dostupnych grafickych modu:

v grub command prompt

# set pager=1
# insmod vbe
#vbeinfo

do /etc/default/grub

GRUB_VIDEO_BACKEND="vbe"
GRUB_TERMINAL_OUTPUT="gfxterm"
#GRUB_FONT_PATH="/boot/grub2/themes/system/DejaVuSans-Bold-14.pf2"
#GRUB_FONT_PATH="/boot/grub2/themes/system/DejaVuSans-10.pf2"
#GRUB_FONT_PATH="/boot/grub2/themes/system/DejaVuSans-12.pf2"
GRUB_FONT_PATH="/boot/grub2/fonts/DejaVuSansMono-24.pf2"
#GRUB_BACKGROUND="/boot/grub2/themes/system/background.png"
GRUB_BACKGROUND="/boot/grub2/fonts/background-sized.png"
#GRUB_THEME="/boot/grub2/themes/system/theme.txt"
GRUB_GFXMODE="1280x720x32"
#GRUB_GFXPAYLOAD_LINUX=keep #text for troubles

ISO BOOT

!!! hlavne musi umet iso, napr debian live iso

custom.cfg nebo (cistejsi) /etc/grub.d/40_custom

UBUNTU

submenu "BackTrack 5 R2 KDE ISO"{
menuentry "BackTrack Text - Persistent CUDA Boot Text Mode" --class ubuntu --class gnu-linux --class gnu --class os {
        savedefault
        load_video
        set gfxpayload=1280x800x32
        insmod gzio
        insmod part_msdos
        insmod ntfs
        insmod ext2
        echo 'Loading BackTrack 5 R2 iso'
	# z BACKTRACK DVD hlavne musi byt zkopirovany adresar /casper (!!!v grub2 se partition pocitaji od 1!!! /dev/sda1 = hd0,msdos1)
        linux (hd0,msdos7)/bt/casper/vmlinuz boot=casper persistent live-media-path=/bt/casper/ text splash intel_iommu=off
        echo 'Loading initial ramdisk ...'
        initrd   (hd0,msdos7)/bt/casper/initrdcuda.gz
}
}

DEBIAN

menuentry "${title}" {
${grub_prep}
        iso_path="${rel_dirname}/${grml}"
        export iso_path
        kernelopts=" $CUSTOM_BOOTOPTIONS $additional_param "
        export kernelopts
        loopback loop "${rel_dirname}/$grml"
        set root=(loop)
        configfile /boot/grub/loopback.cfg
}