help recovering an hd

[carlo]

hi all,
i know this has little to do with sparky, but i do need help with debian, so... here we go

i own an nsa-325v2, some years ago, thanks to doozan forum i could install debian on it
till a couple of months ago everything went fine
but some update or somethig with openmediavault broke ftp, apache and etc
so i had to format

before all the mess happened i could access the 2nd hd via ssh or ftp,
now this is what i get when i try to access it:

FDISK

Disk /dev/mtdblock0: 1 MiB, 1048576 bytes, 2048 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock1: 512 KiB, 524288 bytes, 1024 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock2: 512 KiB, 524288 bytes, 1024 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock3: 512 KiB, 524288 bytes, 1024 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock4: 10 MiB, 10485760 bytes, 20480 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes




Disk /dev/mtdblock6: 47.8 MiB, 50069504 bytes, 97792 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock7: 10 MiB, 10485760 bytes, 20480 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mtdblock8: 47.8 MiB, 50069504 bytes, 97792 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/sda: 298.1 GiB, 320072933376 bytes, 625142448 sectors
Disk model: WDC WD3200KS-00P
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xd632e2ad

Device     Boot Start       End   Sectors   Size Id Type
/dev/sda1        2048 625141759 625139712 298.1G 83 Linux


Disk /dev/sdb: 2.7 TiB, 3000592982016 bytes, 5860533168 sectors
Disk model: WDC WD30EFRX-68E
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: D1070018-0D36-4566-AF9E-C1DC8C69E518

Device      Start        End    Sectors  Size Type
/dev/sdb1    2048     999423     997376  487M Linux swap
/dev/sdb2  999424 5860532223 5859532800  2.7T Microsoft basic data


Disk /dev/md0: 2.7 TiB, 3000079745024 bytes, 5859530752 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

LSBLK

root@openmediavault:~# lsblk
NAME      MAJ:MIN RM   SIZE RO TYPE   MOUNTPOINT
sda         8:0    0 298.1G  0 disk   
└─sda1      8:1    0 298.1G  0 part   /
sdb         8:16   0   2.7T  0 disk   
├─sdb1      8:17   0   487M  0 part   /srv/dev-disk-by-id-ata-WDC_WD30EFRX-68EUZ
└─sdb2      8:18   0   2.7T  0 part   
  └─md0     9:0    0   2.7T  0 linear
mtdblock0  31:0    0     1M  0 disk   
mtdblock1  31:1    0   512K  0 disk   
mtdblock2  31:2    0   512K  0 disk   
mtdblock3  31:3    0   512K  0 disk   
mtdblock4  31:4    0    10M  0 disk   
mtdblock5  31:5    0    10M  0 disk   
mtdblock6  31:6    0  47.8M  0 disk   
mtdblock7  31:7    0    10M  0 disk   
mtdblock8  31:8    0  47.8M  0 disk

cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath]
md0 : active linear sdb2[0]
      2929765376 blocks super 1.2 0k rounding

mdadm --examine /dev/sdb0
mdadm: cannot open /dev/sdb0: No such file or director

mdadm --examine /dev/sdb1
mdadm: No md superblock detected on /dev/sdb1.

mdadm --examine /dev/sdb2
/dev/sdb2:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : ae0b0151:4a62050e:e73ef040:35ee8f4e
           Name : NSA325-v2:0
  Creation Time : Thu Jul 23 00:53:39 2015
     Raid Level : linear
   Raid Devices : 1

Avail Dev Size : 5859530752 (2794.04 GiB 3000.08 GB)
  Used Dev Size : 0
    Data Offset : 2048 sectors
   Super Offset : 8 sectors
   Unused Space : before=1968 sectors, after=0 sectors
          State : clean
    Device UUID : 3eea33c8:e21226cb:66ec754c:06b06634

    Update Time : Thu Jul 23 00:53:39 2015
       Checksum : 5e28e2e5 - correct
         Events : 0

       Rounding : 0K

   Device Role : Active device 0
   Array State : A ('A' == active, '.' == missing, 'R' == replacing)

MOUNT

mount /dev/sdb2 /mnt
mount: /mnt: unknown filesystem type 'linux_raid_member'.
root@openmediavault:/#

i would like to be able to mount the hd without formatting it, nor recovering data in a long and painful way: does it seem possible?