[CentOS] Not getting bootloader installed with CentOS 8 + mdraid

Wed Jul 1 19:05:56 UTC 2020
Chris Adams <linux at cmadams.net>

Once upon a time, Chris Adams <linux at cmadams.net> said:
> I am trying to use a kickstart to install CentOS 8.2 on a server with a
> pair of drives with Linux software RAID 1.  The install completes, but
> the resulting system will not boot - I get "Booting from Hard drive C:"
> from the BIOS (Dell in legacy BIOS mode, not UEFI) and it stops.  If I
> then start the installer in rescue mode and run grub2-install on the two
> drives, it boots okay.

Never mind, this was user error. :)

I have a kickstart that discard unused space in %post to make VM images
smaller, and it tries too hard (and the SSDs listened!) - it got the
unpartitioned space between the partition table and the first partition,
and GRUB2 uses more of that when /boot is on RAID1.  Oops.
Chris Adams <linux at cmadams.net>