GRUB (bootloader)

To change basic settings such as default boot entry and timeout: edit /etc/default/grub and run update-grub afterwards.

Changing/setting a splash image

Places where GRUB will look for a background image:

• GRUB_BACKGROUND="/path/to/image" in etc/default/grub
• First image found in /boot/grub/.
• /usr/share/desktop-base/grub_background.sh
• File listed in the WALLPAPER line in /etc/grub.d/05_debian_theme

It supports JPG, PNG and TGA formats, but be aware of this limitations:

• JPG/JPEG images must be 8-bit (256 color)
• Images should be non-indexed, RGB
• 640x480 is the right resolution for most cases

After setting/placing a new image run update-grub