install guide notes: bootloader

[Chris Murphy]

On Dec 2, 2012, at 11:52 PM, Jack Reed <jreed at redhat.com> wrote:

> How can we expect UEFI to differ though, and will this need to be documented?

The main thing I'm aware of is GRUB Legacy is dropped in favor of GRUB 2. So the references to GRUB Legacy examples and limitations can be dropped.

The command to install GRUB 2 differs between BIOS and UEFI: UEFI destination must be specified, whereas there is a default/assumed location for BIOS.


> Also, I tried to unset my drive for receiving a bootloader but had no luck. Maybe this is because I can only muster one drive in my VM and the button in the instructions you quoted isn't displayed in such a case. But if the button in question is the 'Set as Boot Device' button, then it's not working for me as it should. The tick that marks the drive as the boot device remains.

This appears to be a bug in -29. It worked for me in -32 and is still working for me in -34. However I'm finding a small UI bug where once I deselect it, I can't reselect it until I close the modal dialog and then reenter by clicking on Full disk summary and options.


> On 12/01/2012 08:19 AM, Adam Williamson wrote:
>> 
>> Currently there
>> is no option to install bootloader to a partition, which was possible in
>> oldUI. Installing the bootloader to a partition is done only by those
>> who multiboot various OSes using a 'chainload' system - they have a
>> bootloader in the MBR which 'chainloads' bootloaders for each of their
>> OSes, each of which resides in the / or /boot partition for that OS.

Documentation could state this change in anaconda's behavior, and what's needed to work around this…

>> The plan is for those who have such setups to just not install a
>> bootloader at all, and then do their bootloader configuration manually
>> post-install. Anyone who for some reason doesn't want a bootloader
>> installed to an MBR gets to do their own configuration.


Documentation could state step by step:

- How to choose to not install GRUB at system install time in anaconda.
- Before rebooting after successful install, chroot the newly installed system.
- Use grub2-install --force and specify disk+partition.
- Optionally use grub2-mkconfig so there's a base grub.cfg that should just work.

I have a rough step by step in my head, to make it easy for a user to do this, including identifying the correct disk+partition to install GRUB into.

There is a difference for the command to install to a partition depending on file system: ext4 needs the --force flag; whereas btrfs does not (and cannot as block lists are proscribed on btrfs and merely "not recommended" on ext4).


Chris Murphy