[CentOS] RAID1 bootloader configuration on CentOS 6.x and 7

Sun Mar 29 18:00:17 UTC 2015
Chris Murphy <lists at colorremedies.com>

On Sun, Mar 29, 2015 at 3:43 AM, Niki Kovacs <info at microlinux.fr> wrote:

> Now how would that work with the new GRUB2 under CentOS 7? Or maybe it's
> already installed on both disks, but how would I know that?

grep grub2-install /path/to/anaconda/logs/program.log

I forget if it accepts two devices on a line, or if it takes separate
commands. But

grub2-install /dev/sdX
grub2-install /dev/sdY

That will work on BIOS.

On UEFI this is totally fakaked right now as neither GRUB upstream nor
distros have a proper user friendly solution for this at all. CentOS
7's installer offers an improper user friendly solution which allows
you to RAID 1 the EFI System partitions with md raid.

On UEFI, I do a post-install alteration to make it something more
standard with the way upstream ought to be doing it. That means two
grub.cfg's: a generic one on the ESPs that merely forwards to
/boot/grub2/grub.cfg. That makes the ESP contents generic and never
modified again. And then the real grub.cfg is /boot/grub2/grub.cfg
which can of course then be on raid1 or raid 5 or whatever, and this
is the file that gets updated when there are kernel updates.


-- 
Chris Murphy