We have an umbrella.png image that we want to use as a background for Grub2.
Configuration
Step 1
We need to copy our new image from a home directory to the following one:
# cp /home/$USER/umbrella.png /usr/share/images/desktop-base
Step 2
Open:
# vim /etc/grub.d/05_debian_theme
Find and change the following line to point to our new image:
set_background_image "/usr/share/images/desktop-base/umbrella.png"
Step 3
Open:
# vim /etc/default/grub
And add:
GRUB_BACKGROUND=/usr/share/images/desktop-base/umbrella.png
Step 4
The last thing to do – update grub:
# update-grub