GRUB

GRUB 2

Packages

Exherbo: sys-boot/grub

Gentoo: sys-boot/grub

Installation

# mount /boot

Standard, single drive (SATA/IDE/SCSI)

# grub-install --recheck --no-floppy /dev/sda

Hardware RAID, HP Smart Array CCISS controller

# grub-install --recheck --no-floppy /dev/cciss/c0d0

/sbin/grub-setup: warn: Your embedding area is unusually small. core.img won't fit in it.. /sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged.. /sbin/grub-setup: error: will not proceed with blocklists.

# grub-install --recheck --no-floppy /dev/cciss/c0d0 --force

/sbin/grub-setup: warn: Your embedding area is unusually small. core.img won't fit in it.. /sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged.. Installation finished. No error reported.

Configuration

Note: Manual grub2 configuration should always happen in /etc/default/grub

File: /etc/default/grub

GRUB_DEFAULT="GNU/Linux, current kernel"

Standard, single drive (SATA/IDE/SCSI)

File: /etc/grub.d/40_custom

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'GNU/Linux, current kernel' --class gnu-linux --class gnu --class os {
        load_video 
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root 5e056c75-61b4-42a5-8dd8-9fefd5f5b7fb
        echo    'Loading Linux ...' 
        linux   /vmlinuz root=/dev/sda3 ro init=/sbin/bootchartd
}
menuentry 'GNU/Linux, current kernel (recovery mode)' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)' 
        search --no-floppy --fs-uuid --set=root 5e056c75-61b4-42a5-8dd8-9fefd5f5b7fb
        echo    'Loading Linux ...' 
        linux   /vmlinuz root=/dev/sda3 ro single
}
menuentry 'GNU/Linux, previous kernel' --class gnu-linux --class gnu --class os {
        load_video 
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root 5e056c75-61b4-42a5-8dd8-9fefd5f5b7fb
        echo    'Loading Linux ...' 
        linux   /vmlinuz.old root=/dev/sda3 ro
}
menuentry 'GNU/Linux, previous kernel (recovery mode)' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root 5e056c75-61b4-42a5-8dd8-9fefd5f5b7fb
        echo    'Loading Linux ...'
        linux   /vmlinuz.old root=/dev/sda3 ro single
}

Hardware RAID, HP Smart Array CCISS controller

File: /etc/grub.d/40_custom

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'GNU/Linux, current kernel' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root b3727853-ae78-4a00-b21c-7b974c233e1c
        echo    'Loading Linux ...'
        linux   /vmlinuzo root=/dev/cciss/c0d0p3 ro
}
menuentry 'GNU/Linux, current kernel (recovery mode)' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root b3727853-ae78-4a00-b21c-7b974c233e1c
        echo    'Loading Linux ...'
        linux   /vmlinuz root=/dev/cciss/c0d0p3 ro single
}
menuentry 'GNU/Linux, previous kernel' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root b3727853-ae78-4a00-b21c-7b974c233e1c
        echo    'Loading Linux ...'
        linux   /vmlinuz.old root=/dev/cciss/c0d0p3 ro
}
menuentry 'GNU/Linux, previous kernel (recovery mode)' --class gnu-linux --class gnu --class os {
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root b3727853-ae78-4a00-b21c-7b974c233e1c
        echo    'Loading Linux ...'
        linux   /vmlinuz.old root=/dev/cciss/c0d0p3 ro single
}

Generate grub.cfg

Warning: Running the following command will overwrite any changes in grub.cfg you manually made

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

# umount /boot

Updating Grub 2

# mount /boot

# grub-install --recheck --no-floppy /dev/sda

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

# umount /boot

Optional: Serial Console

File: /etc/default/grub

GRUB_TERMINAL=serial
GRUB_SERIAL=COMMAND="serial --unit=0 --speed=57600 --word=8 --parity=no --stop=1"
GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,57600"

Regenerate your grub.cfg for the changes to take effect.

# mount /boot && grub-mkconfig -o /boot/grub/grub.cfg && umount /boot

If you want to be able to login to your system via the serial console you need to edit /etc/inittab.

File: /etc/inittab

Uncomment the s0 entry and change the speed to your needs.

# SERIAL CONSOLES
s0:12345:respawn:/sbin/agetty 57600 ttyS0 vt100
#s1:12345:respawn:/sbin/agetty 9600 ttyS1 vt100