Ubuntu 11.04: customizing grub splash logo[]
Steps to replace the default Grub splash screen with one's own:
1. Modify /etc/default/grub by
- commenting off the line below:
#GRUB_HIDDEN_TIMEOUT=0
- changing the setting for GRUB_CMDLINE_LINUX_DEFAULT below:
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX_DEFAULT="splash"
2. Create a 640x480 PNG file and copy it to /etc/grub.d directory; say the filename is ytt_ubuntu.png;
3. Edit /etc/grub.d/05_debian_theme by assigning to GRUB_BACKGROUND the pathname to ytt_ubuntu.png which was just copied:
GRUB_BACKGROUND="/etc/grub.d/ytt_ubuntu.png" # First check whether the user has specified a background image explicitly. # If so, try to use it. Don't try the other possibilities in that case # (#608263). if [ -n "${GRUB_BACKGROUND+x}" ]; then set_background_image "${GRUB_BACKGROUND}" || set_default_theme exit 0 fi
4. Issue the sudo update-grub2 command and verify it completes successfully.
$ sudo update-grub2
5. Reboot Ubuntu Linux OS.
Most of the steps above were learned from
this article.
(As an aside, the same author has written another article on how to
customize Ubuntu boot splash screen and logo.)
More side notes:
/etc/grub.d/00_header contains scripts like the following:
cat << EOF if [ -s \$prefix/grubenv ]; then set have_grubenv=true load_env fi EOF
The lines enclosed by cat and EOF will be written to /boot/grub/grub.cfg
Furthermore, you may add your own script files in /etc/grub.d; after running "sudo update-grub2", the added script will be inserted into /boot/grub/grub.cfg
To Be Explored:
- How to write one's own .mod Grub modules, so that they can be loaded by Grub (by using insmod -- note that might not be the same insmod for the Linux kernel, though.)?
Q&A's:
- 'cp' memory leaks?
[Ans:] Quotes from this discussion thread:
``Linux makes efficient use of the system's memory. That memory allocated
to "buffers" and "cached" is available for your programs to use, but in the mean time Linux is keeping around a memory of what it last saw on the disk or CD, so that it doesn't have to go to the physical medium again the next time you want to look at the same information."
One observation: If you delete the big files just copied either from or to the source/destination right after doing 'cp', you shall see from the 'top' command window that the cached memory is freed.