Can`t mount drive from NAS (JBOD)

accsi · 10-03-2013, 04:22 AM

Hi!

I have a Synology NAS with two disks with JBOD. One of them is chrashed. How can i mount them in Ubuntu? With fdisk -l ican see both of them, sda and sdb. I see md3 too (md3 : active raid1 sdb3[0])
I can mount md3, but it is just the second disk, not the first, wich chrased.
I tried this: sudo mount /dev/sda5 /media/newhd
Result: mount: unknown filesystem type 'linux_raid_member'

I`m new with linux, don`t know what information do you need.

corp769 · 10-03-2013, 07:45 AM

Hello and welcome to LQ!

You are better off taking the disks out and mounting them manually, and then performing whatever you need to with either disk. This could be either via an external enclosure and adapter, or via the SATA/IDE connections in a desktop computer. What exactly are you wanting to do? Attempt to extract the data from the bad disk? Have a look at the following link, as it is a start: https://help.ubuntu.com/community/DataRecovery

Particularly, look at the PhotoRec program; you can use that to try to recover as much data as you can from the damaged/corrupted hard drive.

Cheers!

Josh

accsi · 10-03-2013, 08:18 AM

Thank You for your help Josh!

I took off the disks from the NAS and tried to mount manually to a linux PC. One of them can be mounted, but the other (the crashed) i can`t. I want to extract the data from the bad disk.

I will try PhotoRec. Now its running TestDisk DeeperSearch.

Thank You again!

accsi

corp769 · 10-03-2013, 08:46 AM

Well what is the output/errors that you are getting when you try to mount it, and how exactly are you trying to mount it?

accsi · 10-03-2013, 10:13 AM

First i made this:

Code:

root@ubuntu:~# fdisk -l

Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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 identifier: 0x048f18ed

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1             256     4980735     2490240   fd  Linux raid autodetect
/dev/sda2         4980736     9175039     2097152   fd  Linux raid autodetect
/dev/sda3         9437184  1953511007   972036912    f  W95 Ext'd (LBA)
/dev/sda5         9453280  1953511007   972028864   fd  Linux raid autodetect

WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdb: 4009 MB, 4009754624 bytes
255 heads, 63 sectors/track, 487 cylinders, total 7831552 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 identifier: 0x71bafca0

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           0     1607679      803840    0  Empty
/dev/sdb2         1595952     1600495        2272   ef  EFI (FAT-12/16/32)

WARNING: GPT (GUID Partition Table) detected on '/dev/sdb1'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdb1: 823 MB, 823132160 bytes
255 heads, 63 sectors/track, 100 cylinders, total 1607680 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 identifier: 0x71bafca0

     Device Boot      Start         End      Blocks   Id  System
/dev/sdb1p1   *           0     1607679      803840    0  Empty
/dev/sdb1p2         1595952     1600495        2272   ef  EFI (FAT-12/16/32)
root@ubuntu:~#

The crashed drive is the first in the list (/dev/sda)
I tought sda5 is to be mounted

Code:

root@ubuntu:~# mount /dev/sda5 /mnt
mount: unknown filesystem type 'linux_raid_member'
root@ubuntu:~#

corp769 · 10-03-2013, 11:34 AM

According to your output, you are using the wrong tool; since both hard drives have GPT partition tables, you will need to use an utility for the proper job - gdisk, cgdisk, gptfdisk, all the way down to GNU parted, gparted, etc. Have a look here for more general information regarding what GPT partitioning is, and the advantages it has over MBR, etc:
http://en.wikipedia.org/wiki/GUID_Partition_Table
https://wiki.archlinux.org/index.php...artition_Table

I know the last one is on the arch website, but their wiki has really great resources available to the linux-wide community.

Now that being said, on Ubuntu, you will not have your more typical "/var/log/messages", but rather look in /var/log/syslog, and in your dmesg output for any warnings and/or errors related to your problem. I also notice that you tried mounting the device without specifying any options; You should try using your -o argument to specify what file system the mount point should be mounted as, along with any other options, such as read-only, read-write, etc. Have a look at the man page for further information on this, as it is quite extensive.