Synology Raid repair

Synology recover.txt

Backup raid config
------------------
DiskStation> cd /etc/space
DiskStation> ls -lh
DiskStation> cat space_history_20130806_135258.xml

Corrupted system partition
--------------------------
DiskStation> cat /proc/mdstat
md0 : active raid1 sda1[0]
      2490176 blocks [12/1] [U___________]

md1 : active raid1 sdl2[6] sdk2[5] sdj2[4] sdi2[3] sdh2[2] sdg2[1] sda2[0]
      2097088 blocks [14/7] [UUUUUUU_______]

md2 : active raid1 sda3[0]
      53782976 blocks super 1.2 [1/1] [U]

Stop system volumes
-------------------
real console mode since it will crash "gate one"
syno_poweroff_task [dsm 5]
mdadm --grow -n 1 /dev/md0
mdadm --grow -n 1 /dev/md1
mdadm --grow -n 9 /dev/md0
mdadm --grow -n 9 /dev/md1
mdadm /dev/md0 -a /dev/sd[ghijklmn]1
mdadm /dev/md1 -a /dev/sd[ghijklmn]2


Degraded raid
-------------
http://www.bitgeek.co.uk/recovering-deleted-volumes-synology-diskstation/
http://superuser.com/questions/603481/how-do-i-reactivate-my-mdadm-raid5-array
http://superuser.com/questions/550064/how-mount-find-recover-data-in-hdd-outside-of-synology-box

DiskStation> sfdisk -l
DiskStation> mdadm -E /dev/sd[mn]3
DiskStation> cat /proc/mdstat
mdadm --detail /dev/md3

DiskStation> mdadm --stop /dev/md3
DiskStation> mdadm --assemble --force /dev/md3 /dev/sd[ghijklmn]3
DiskStation> mdadm --assemble -s
mdadm: /dev/md/3 has been started with 8 drives.
mdadm: /dev/md/1_0 has been started with 2 drives (out of 14).

DiskStation> vgchange -ay /dev/vg1
DiskStation> lvdisplay vg1
DiskStation> mount /dev/vg1/volume_2 -o ro /volume2