Grub2
Notes here should apply to all distributions using grub2.
Remember that any time a change is made to grub you need to run the command sudo update-grub. If you fail to take this step the changes will not be incorporated into the boot configuration.
Some notes taken from this web page
BigDelay
Default
Files
GFXMode
Memtest86+
MenuHighlight
Random
RecoveryMode
SplashImages
StartupManager
TimeOut
Version
FedoraGrub2
Default Timeout
To change the default timeout for the boot menu, edit the file /etc/default/grub. There is a line that reads
GRUB_TIMEOUT=xx
Change it to whatever you wish. Save and exit. Remember to run sudo update-grub. Next time you boot the system the new value will be incorporated.
What version of grub?
Check the installed version of grub with grub-install -v.
glenn@leonardo:~$ grub-install -v grub-install (GNU GRUB 1.97~beta4)
GRUB2 Files
/boot/grub/grub.cfg
/etc/default/grub
/etc/grub.d (folder)
Default OS
The default OS is determined in the file /etc/default/grub. There is a line that reads
GRUB_DEFAULT=x
Change that number to reflect the operating system you want to be the default. I've changed mine to GRUB_DEFAULT=5. I have 6 entries in the menu. The last one is Fedora. Since I'm a Fedora user and that's my main OS I want it to be the default. Remember to run sudo update-grub. Next time you boot the system the new value will be incorporated.
glenn@leonardo:~$ sudo update-grub Generating grub.cfg ... Found linux image: /boot/vmlinuz-2.6.31-14-generic Found initrd image: /boot/initrd.img-2.6.31-14-generic Found memtest86+ image: /boot/memtest86+.bin Found Windows 7 (loader) on /dev/sda2 Found Fedora release 11.92 (Rawhide) on /dev/sda6 done
Splash Images with grub2
Install the grub2-splashimages package. On my Ubuntu 9.10 install this is done with apt-get.
sudo apt-get install grub2-splashimages
When Fedora adopts grub2 I'm sure that the installation will be something like this.
sudo yum install grub2-splashimages
Once this package is installed the files, on the Ubuntu system, reside in /usr/share/images/grub.
[glenn@leonardo ~]$ ls /usr/share/images/grub/ 050817-N-3488C-028.tga Flower_jtca001.tga Plasma-lamp.tga 2006-02-15_Piping.tga Fly-Angel.tga Sparkler.tga Aesculus_hippocastanum_fruit.tga Glasses_800_edit.tga TulipStair_QueensHouse_Greenwich.tga Apollo_17_The_Last_Moon_Shot_Edit1.tga Hortensia-1.tga Windbuchencom.tga B-1B_over_the_pacific_ocean.tga Lake_mapourika_NZ.tga BonsaiTridentMaple.tga Moraine_Lake_17092005.tga
To use one of these images for your boot splash background, open the file /etc/grub.d/05_debian_theme as root for editing. Find the line that reads
for i in {/boot/grub,/usr/share/images/desktop-base}/moreblue-orbit-grub.{png,tga} ; do
This is the line that needs to be modified. On my system I simply commented the original line out and added a new one using the path to the desired image file. I've chosen the file Lake_mapourika_NZ.tga as my background. Here's the newly added line, below the commented out original line.
#for i in {/boot/grub,/usr/share/images/desktop-base}/moreblue-orbit-grub.{png,tga} ; do
for i in {/boot/grub,/usr/share/images/grub}/Lake_mapourika_NZ.{png,tga} ; do
Save your changes and run sudo update-grub. If all goes well you will see output stating that the image was found.
[glenn@leonardo ~]$ sudo update-grub Password: Generating grub.cfg ... Found Debian background: Lake_mapourika_NZ.tga Found linux image: /boot/vmlinuz-2.6.31-14-generic Found initrd image: /boot/initrd.img-2.6.31-14-generic Found memtest86+ image: /boot/memtest86+.bin Found Windows 7 (loader) on /dev/sda2 Found Fedora release 11.92 (Rawhide) on /dev/sda6 done
Notice the line reading Found Debian background: Lake_mapourika_NZ.tga. This is good. The next reboot will show that image as the bootsplash background.
Menu Colors / Highlighting
This feature is set in the file /etc/grub.d/05_debian_theme. There is a section near the bottom of the file that reads, by default
set color_normal=black/black set color_highlight=magenta/black
I changed the second line to read
set color_normal=black/black set color_highlight=white/blue
This will give me a blue bar with white text. Remember to run sudo update-grub after you make this change so that it is incorporated into the menu.
Random thoughts / notes
Booting Fedora along with Ubuntu, Windows Vista and Windows 7. Tonight there was a kernel update for Fedora 12. I rebooted and the only Fedora kernel offered was the older one. Seems I have to boot Ubuntu and run sudo update-grub before the new kernel will be offered by grub2.
Seems any change to the Fedora boot menu will not be reflected in the grub2 boot menu until I run sudo update-grub.
Memtest86+ - Apparently the only way to remove this menu entry is to remove the executable bit from the file /etc/grub.d/20_memtest86+.
sudo chmod -x /etc/grub.d/20_memtest86+ sudo update-grub
I'm finding it somewhat of a pain in the ass to be running sudo update-grub every time I get a Fedora kernel update. Unless I'm missing something this means that after I update Fedora I need to boot to Ubuntu to update grub and then boot back to Fedora to use the new kernel. Clumsy.
Long boot delay
When I boot my desktop box there is a long delay, probably 40 seconds or so, where GRUB2 seems to be doing a lot of disk reading. Then once a decision is reached there is another delay of 3-5 seconds before the boot loader actually presents a boot menu. Doesn't seem like this is the correct behaviour.
Info here
The information contained in that forum thread helped me solve my problem. I have three hard disks in the computer, two are EIDE and one is SATA. They are set up this way:
Primary Master: 80GB EIDE Secondary Master: 160GB EIDE SATA: 500GB
Ubuntu sees these disks as /dev/sda, /dev/sdb and /dev/sdc respectively. I fiddled with the commands mentioned in the forum thread until I got it right realizing that Ubuntu is actually installed on /dev/sdb. Some shots of my experiment. This first screen I just pressed enter.
On this screen I also just pressed enter.
On this screen I again pressed enter. No changes yet.
On this screen I selected sdb since this is where Ubuntu is installed.
Back to the terminal where dpkg-reconfigure grub-pc finishes up.
Once complete I rebooted, changed the BIOS so that the 160GB drive was the "first" drive and rebooted again. Success! Now grub loads as it should, not 40 seconds after it should have.
Startup Manager
A graphical application that allows the user to change some of the basic functions / settings of the boot loader. Installed on an Ubuntu system with the command
sudo apt-get install startupmanager
The application can be found under System > Administration > Startup Manager.
Do not display recovery mode menu option
I don't want to see "recovery mode" offered in the boot menu. To accomplish this, edit the file /etc/default/grub. Find the line that reads
#GRUB_DISABLE_LINUX_RECOVERY=true
Remove the # from in front of that line. Run sudo update-grub. When you reboot you will not see a Recovery Mode option.
GFXMode
Replacing vga=791 in the boot menu. In the file /etc/default/grub find the line that reads
#GRUB_GFXMODE=640x480
Uncomment and change to 800x600, 1024x768, etc.
Hmmmm... That only changes the resolution of the screen for the boot menu, not the vga mode of the other OS's.
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