GRUB2 general configuration

grub-mkconfig, default is output to stdout

Valid keys are in the /etc/default/grub

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Manually add the menu entry)

1) Adding extra custom menu entries to the end of the list can be done by editing /etc/grub.d/40_custom
Alternatively, in/etc/grub.d folder, create the file XX_whichos where XX is the number. It is used to indicate the ordering of the menuitem.

2) After the file is edited, make it executable.
sudo chmod +x /etc/grub.d/XX_whichos

3) Execute "update-grub2" command

The updated grub.cfg will be placed at /boot/grub/ folder

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For traditional partition,

Windows 7 entry (first harddisk, 2nd primary partition)

menuentry ‘Windows 7′ {
set root=’(hd0,msdos2)’
chainloader +1
}

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For EFI,

menuentry "Windows 7" {

insmod part_gpt

insmod fat

insmod search_fs_uuid

insmod chain

search --fs-uuid --no-floppy --set=root 080F-E6DA

chainloader (${root})/efi/Microsoft/Boot/bootmgfw.efi

}

UUID can be obtained from blkid

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