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Revision as of 07:55, 14 August 2010 by Blitz303 (talk | contribs) (I have tested with Fedora 12)

Feature Name




This is very early stage, but I'm trying to document the progress here rather than just locally

Switch to using grub2 instead of grub legacy for boot loading an installed x86 system


Current status

  • Targeted release: Releases/13
  • Last updated: 2009-07-08
  • Percentage of completion: 0%

Detailed Description

We currently use what is essentially a fork of GRUB 0.9x in Fedora for a variety of historical reasons. It would be nice to get back to the upstream developed version, even though it is in many ways an entirely new project.

GRUB2 is still considered "in development", but GRUB 0.9x was always considered an alpha, so maybe that's not an issue. The upstream wiki can be found at

Benefit to Fedora

The main benefit is moving to a newer upstream version that hopefully more people are working on. That said, it's not a small task, hence why we're not going to try to get it done in the super-short Fedora 12 timeframe.

There could also be new functionality, but that's currently less of the driver.


The changes are somewhat localized, but there's a lot to be done. The current status based on the testing I've done so far.

What Currently Works

  • MBR Bios booting as chainloaded from grub1 works
  • Booting from the MBR works
  • Graphics mode works
    • You have to have freetype2-devel installed and build with --enable-mkfont
    • Also had to grab the unifont from
    • Simple hacked up module to load a background image is okay. Could certainly be made better
  • Creating /usr/local/etc/defaults/grub (would be /etc, but prefix=/usr/local) allowed me to set the following
    • default timeout, default distro name, default to graphics mode
    • some of this is lame and should get auto-detected (eg, parse /etc/system-release)

Things that still have to be tested/worked on

  • EFI mode
  • passwords -- Debian and Ubuntu are working on this upstream as of 8 July
  • hidden menu support that we use for flicker-less boot
  • serial terminal support (with the timeouts)
  • bootonce
  • Always adding single user entry is not so good -- set GRUB_DISABLE_LINUX_RECOVERY in /etc/default/grub
  • Chainloading various versions of Windows
  • Auto-detection of Windows and adding it to the config file
  • Can we ship the unifont ?
    • Also, as I had it "built", the font wasn't quite right
  • Ensuring all the other features we have and care about are present (if someone wants to make a list of these, it would be helpful)
  • Documentation, documentation, documentation...

External things that would need work

  • anaconda needs to be able to create the new file. Or at least run grub-mkconf
  • grubby to update. Or phase out for grub-updconf?

How To Test

It is very easy to test from Grub Legacy type environment, but we will also need to test from Anaconda/Firstinstall.

From an Installed System with Grub Legacy

This was adapted from

The following will automatically generate a GRUB2 configuration file including kernels images within your /boot folder, using the auto configuration scripts in /etc/grub.d, the -o specifices an output file, here the default, /boot/grub2/grub.cfg:

grub2-mkconfig -o /boot/grub2/grub.cfg

Testing With Chain Loading

GRUB2 includes a boot image that's loadable from GRUB Legacy, so you can try it out without wiping out your existing, working MBR. To set up GRUB2 without actually writing to the MBR, run

grub2-install --grub-setup=/bin/true /dev/sda

Writing to the MBR

If that works, you can go on testing to writing to your MBR. Same steps as above, but don't tell grub to run the dummy setup program /bin/true

grub2-install /dev/sda

Congratulations! You've reached the point of now return! If you can't boot now you will need to run a rescue CD

From a DVD with Anaconda

TBD as things get fleshed out more

User Experience

Ultimately, the main thing a user could change is the different config file (grub.cfg vs grub.conf) and the different syntax in the config file. During the normal boot process, the idea should be that it's not that noticeable


We'll have to be sure to update anaconda for the new config file format and also deal with things like grubby (which updates boot loader configs)

Contingency Plan

Keep using GRUB legacy


  • The only docs right now are at the upstream site, but they're slim at best.

Release Notes

  • Yep, we'll need some!

Comments and Discussion