Hi, I'm currently writing a little documentation on how to install CentOS 7 on manually partitioned disks, e. g. boot in Rescue Mode first, partition using fdisk or gdisk, reboot, start the installer and use the installer to format these partitions. I have a total of 9 (3 x 3) situations: * single disk (BIOS+MBR, BIOS+GPT, UEFI) * RAID 1 on 2 disks (BIOS+MBR, BIOS+GPT, UEFI) * RAID 6 on 4 disks (BIOS+ BR, BIOS+GPT, UEFI) Everything works fine so far and I've completed seven out of nine of these setups. But right now I'm stuck with a problem on how to manually setup RAID 1 with UEFI. Here's what I do. Fire up gdisk on /dev/sda. Create 4 RAID partitions (FD00): * 200 MB for /dev/md/EFI * 500 MB for /dev/md/boot * 4 GB for /dev/md/swap * 55 MB for /dev/md/root Create the RAID arrays: # mdadm --create /dev/md/EFI --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda1 /dev/sdb1 mdadm: array /dev/md/boot started # mdadm --create /dev/md/boot --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda2 /dev/sdb2 mdadm: array /dev/md/boot started # mdadm --create /dev/md/swap --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md/swap started # mdadm --create /dev/md/root --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda4 /dev/sdb4 mdadm: array /dev/md/root started And then I reboot, fire up the installer and assign these RAID arrays respectively to the EFI system partition as well as /boot, swap and /. Unfortunately I won't even reach the GRUB menu on boot. Only thing I get after the initial reboot is the EFI shell. Now I've tried this again, this time partitioning *and* formating using Anaconda. * one mountpoint for /boot/efi (RAID 1) * one mountpoint for /boot (RAID 1) * one mountpoint for swap (RAID 1) * one mountpoint for / (RAID 1) After the initial reboot, everything works fine. EFI on a RAID 1 array apparently works. So what am I missing and/or doing wrong in my manual setup? Cheers, Niki -- Microlinux - Solutions informatiques durables 7, place de l'église - 30730 Montpezat Site : https://www.microlinux.fr Blog : https://blog.microlinux.fr Mail : info at microlinux.fr Tél. : 04 66 63 10 32 Mob. : 06 51 80 12 12