Debian 8.2 установка GRUB в MBR на sda и sdb

# ======= RAID/LVM & Partitioning ================
d-i partman-lvm/device_remove_lvm boolean true
d-i partman-md/device_remove_md boolean true
d-i partman-auto/purge_lvm_from_device  boolean true
d-i partman-auto/disk string /dev/sda /dev/sdb
d-i partman-auto/method string raid
d-i partman-auto-lvm/new_vg_name string AzK
d-i partman-auto-lvm/guided_size string max
d-i partman-auto/choose_recipe select multiraid 
d-i partman-auto/expert_recipe string               \
    multiraid  ::                                   \
     512 10 512 raid                                \
       $primary{ } $lvmok{ } lv_name{ boot }        \
       $bootable{ }          			    \
       method{ raid }                               \
     .                                              \
     5120 30 5120 ext4                              \
       $defaultignore $lvmok{ } lv_name{ root }     \
       method{ format } format{ }                   \
       use_filesystem{ } filesystem{ ext4 }         \
       mountpoint{ / }                              \
     .                                              \
     2048 35 2048 linux-swap                        \
       $defaultignore $lvmok{ } lv_name{ swap }     \
       method{ swap } format{ }                     \
     .                                              \
     4096 40 4096 ext4                              \
       $defaultignore $lvmok{ } lv_name{ tmp }      \
       method{ format } format{ }                   \
       use_filesystem{ } filesystem{ ext4 }         \
       mountpoint{ /tmp }                           \
     .                                              \
     8192 50 8192 ext4                              \
       $defaultignore $lvmok{ } lv_name{ var }      \
       method{ format } format{ }                   \
       use_filesystem{ } filesystem{ ext4 }         \
       mountpoint{ /var }                           \
     .                                              \
     8192 60 8192 ext4                              \
       $defaultignore $lvmok{ } lv_name{ usr }      \
       method{ format } format{ }                   \
       use_filesystem{ } filesystem{ ext4 }         \
       mountpoint{ /usr }                           \
     .                                              \
     512 70 -1 ext4                                 \
       $defaultignore $lvmok{ } lv_name{ home }     \
       method{ format } format{ }                   \
       use_filesystem{ } filesystem{ ext4 }         \
       mountpoint{ /home }                          \
       method{ lvm }                                \
     .
d-i partman-auto-raid/recipe string                 \
    1 2 0 lvm  -      /dev/sda1#/dev/sdb1       .

d-i preseed/late_command string in-target lvremove -f AzK/home
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true
d-i partman-lvm/confirm boolean true
d-i partman-md/confirm boolean true
d-i partman-md/confirm_nooverwrite boolean true
d-i partman/mount_style select label
d-i mdadm/boot_degraded boolean false 

grub-install /dev/sda
grub-install /dev/sdb
update-grub

# df -h
Filesystem            Size  Used Avail Use% Mounted on
rootfs                4.7G  278M  4.2G   7% /
udev                   10M     0   10M   0% /dev
tmpfs                 402M  1.8M  401M   1% /run
/dev/mapper/AzK-root  4.7G  278M  4.2G   7% /
tmpfs                 5.0M   12K  5.0M   1% /run/lock
tmpfs                 804M     0  804M   0% /run/shm
/dev/mapper/AzK-home  268G   66G  189G  26% /home
/dev/mapper/AzK-tmp   3.8G   72M  3.5G   2% /tmp
/dev/mapper/AzK-usr   7.6G  783M  6.4G  11% /usr
/dev/mapper/AzK-var   7.6G  448M  6.7G   7% /var

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/dm-0             4.6G  232M  4.1G   6% /
udev                   10M     0   10M   0% /dev
tmpfs                 752M  9.2M  743M   2% /run
/dev/dm-2             7.4G  671M  6.4G  10% /usr
tmpfs                 1.9G     0  1.9G   0% /dev/shm
tmpfs                 5.0M     0  5.0M   0% /run/lock
tmpfs                 1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/AzK-var   7.4G  214M  6.8G   3% /var
/dev/mapper/AzK-tmp   3.7G  7.7M  3.5G   1% /tmp
/dev/mapper/AzK-home   48G   52M   45G   1% /home

Loading, please wait...
fsck from util-linux 2.25.2
/dev/mapper/AzK-root: clean, 7480/312624 files, 111710/1249280 blocks
fsck from util-linux 2.25.2
/dev/aapper/AzK-usr: clean, 33607/499968 files, 235833/1999872 blocks
[	6.343894] kvm: disabled by bios
[	7.055195] systemd-fsck [399]: /dev/mapper/AzK-tmp: clean, 15/249984 files, 34037/999424 blocks
[	7.133820] systemd-fsck [403]: /dev/mapper/AzK-home: clean, 34/3162112 files, 244526/12647424 blocks
[	7.163081] systemd-fsck [410]: /dev/mapper/Azk-var: clean, 3317/499968 files, 120654/1999872 blocks

...
Volume group "AzK" not found
Skipping volume group AzK
Unable to find LVM volume AzK/root
Gave up Halting for root device. Common problems:
- Boot args (cat /proc/cmdline)
- Check rootdelays= (did the system wait long enough?)
- Check root= (did the system wait for the right device?)
- Missing modules (cat /proc/modules; ls /dev)

ALERT! /dev/mapper/AzK-root does not exist. Dropping to a shell!
modprobe: module ehci-orion not found in modules.dep

BusyBox vl.22.1 (Debian 1:1.22.0-9+deb8ul) built-in shell (ash)
Enter 'help' for a list of built-in commands.

/bin/sh: can't access tty; Job control tuned off
(initramfs)