Let me see if I can, um, reboot this thread....
I made a RAID 1 of two raw disks, /dev/sda and /dev/sdb, *not* /dev/sdax /dev/sdbx. Then I installed CentOS 7 on the RAID, with /boot, /, and swap being partitions on the RAID. My problem is that grub2-install absolutely and resolutely refuses to install on /dev/sda or /dev/sdb.
I've currently got it up in a half-assed rescue mode, and have mount -o bind /dev, /proc/ and /sys under /mnt/sysimage, and chrooted there. That's where I'm trying to do my grub2-install.
So: 1. *Is* there space for grub2 to install the bootloader under where the mdadm starts? Or do I have to partition the disks (/dev/sda1 100%, ditto /dev/sdb1, then create the RAID 1 with the partitions, and *then* grub2-install? 2. I *think* that one thing that grub2-install is complaining about is that it can't find /boot/grub2. I've tried doing it with $ grub2-install --boot-directory=/boot /dev/sda and $ grub2-install --boot-directory=/dev/md127p1/ /dev/sda and $ grub2-install --boot-directory=/dev/md127pw/boot /dev/sda and it tells me it cannot find the canonical path for the grub2 directory. Is there some way to specify where it should fund /boot/grub2 that I've missed?
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