Boot rescue centos mode with live disk edit /etc/mdadm.conf DEVICE /dev/sda1 DEVICE /dev/sdb1 mdadm --examine --scan mdadm --examine --scan >> /etc/mdadm.conf mdadm --assemble --scan /dev/mdX mount /dev/mdX2 /mnt/sysroot mount /dev/mdX1 /mnt/sysroot/boot mount --bind /sys /mnt/sysroot/sys mount --bind /proc /mnt/sysroot/proc mount --bind /dev /mnt/sysroot/dev chroot /mnt/sysroot/ grub2-mkconfig -o /boot/grub2/grub.cfg exit umount /mnt/sysroot/sys umount /mnt/sysroot/proc umount /mnt/sysroot/dev umount /mnt/sysroot/boot umount /mnt/sysroot/ sync reboot