Hello.... The problem is still exists. I think maybe not the grub, maybe the software raid broken..
8 root@grml ~ # dumpe2fs /dev/sda2 | grep superblock :(
dumpe2fs 1.42.9 (4-Feb-2014)
Primary superblock at 0, Group descriptors at 1-117
Backup superblock at 32768, Group descriptors at 32769-32885
Backup superblock at 98304, Group descriptors at 98305-98421
Backup superblock at 163840, Group descriptors at 163841-163957
Backup superblock at 229376, Group descriptors at 229377-229493
Backup superblock at 294912, Group descriptors at 294913-295029
Backup superblock at 819200, Group descriptors at 819201-819317
Backup superblock at 884736, Group descriptors at 884737-884853
Backup superblock at 1605632, Group descriptors at 1605633-1605749
Backup superblock at 2654208, Group descriptors at 2654209-2654325
Backup superblock at 4096000, Group descriptors at 4096001-4096117
Backup superblock at 7962624, Group descriptors at 7962625-7962741
Backup superblock at 11239424, Group descriptors at 11239425-11239541
Backup superblock at 20480000, Group descriptors at 20480001-20480117
Backup superblock at 23887872, Group descriptors at 23887873-23887989
Backup superblock at 71663616, Group descriptors at 71663617-71663733
Backup superblock at 78675968, Group descriptors at 78675969-78676085
Backup superblock at 102400000, Group descriptors at 102400001-102400117
Backup superblock at 214990848, Group descriptors at 214990849-214990965
root@grml ~ # fsck -b 32768 /dev/sda2
fsck from util-linux 2.20.1
fsck: fsck.linux_raid_member: not found
fsck: error 2 while executing fsck.linux_raid_member for /dev/sda2
2 root@grml ~ # cat /proc/mdstat :(
Personalities : [raid1]
md127 : active raid1 sdb2[1] sda2[0]
1951465280 blocks super 1.0 [2/2] [UU]
bitmap: 0/15 pages [0KB], 65536KB chunk
unused devices: <none>
So, the md126 is missing. maybe thats the problem? what do you think?