install grub

If server loaded in Recovery Rescue (or from live cd):

1. mount root filesystem 
   cd
   /mnt
   
   mkdir md127
   
   mount /dev/md127 /mnt
   /md127
2. Mount boot
    
   mount /dev/md126 /mnt/md127/boot
3. Mount 
   /dev
   , 
   /proc
    и 
   /sys
   
   
   mount --bind /dev /mnt/md127/dev<br>mount --bind /proc /mnt/md127/proc<br>mount --bind /sys /mnt/md127/sys
4. mount efi partition
   mount /dev/nvme0n1p3 /mnt/md127/boot/efi
5. modprobe efivarfs
   modprobe efivarfs
6.  
   chroot
    to mounted filesystem
   
   chroot /mnt
   /md126
7. 
   
   mount -t efivarfs efivarfs /sys/firmware/efi/efivars
8. Install Grub
   
   grub-install /dev/nvme0n1
   
   grub-install /dev/nvme1n1
   
9. Reboot