Need advise for RAID5 Not active, Force rebuild?

[wat_up]

Hello! i Have a TS-809 pro on firmware 3.2.7(been away from work for a year) running on RAID5 with 8 WD green disks(i know it's horrible).

would you take the risk on force rebbuild this array?

Code: Select all

[~] # mdadm -D /dev/md0
/dev/md0:
        Version : 00.90.03
  Creation Time : Tue Jun 22 23:42:20 2010
     Raid Level : raid5
  Used Dev Size : 1951945600 (1861.52 GiB 1998.79 GB)
   Raid Devices : 8
  Total Devices : 6
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Mon Sep 22 21:19:28 2014
          State : active, degraded, Not Started
 Active Devices : 6
Working Devices : 6
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : d979105e:1a1870af:e2b145e0:dadd82e0
         Events : 0.283476

    Number   Major   Minor   RaidDevice State
       0       8        3        0      active sync   /dev/sda3
       1       8       19        1      active sync   /dev/sdb3
       2       0        0        2      removed
       3       0        0        3      removed
       4       8       67        4      active sync   /dev/sde3
       5       8       83        5      active sync   /dev/sdf3
       6       8       99        6      active sync   /dev/sdg3
       7       8      115        7      active sync   /dev/sdh3
[~] # mdadm -E /dev/sdb3
/dev/sdb3:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : d979105e:1a1870af:e2b145e0:dadd82e0
  Creation Time : Tue Jun 22 23:42:20 2010
     Raid Level : raid5
  Used Dev Size : 1951945600 (1861.52 GiB 1998.79 GB)
     Array Size : 13663619200 (13030.64 GiB 13991.55 GB)
   Raid Devices : 8
  Total Devices : 7
Preferred Minor : 0

    Update Time : Mon Sep 22 21:19:28 2014
          State : clean
 Active Devices : 7
Working Devices : 7
 Failed Devices : 1
  Spare Devices : 0
       Checksum : 6eef567c - correct
         Events : 0.283476

         Layout : left-symmetric
     Chunk Size : 64K

      Number   Major   Minor   RaidDevice State
this     1       8       19        1      active sync   /dev/sdb3

   0     0       8        3        0      active sync   /dev/sda3
   1     1       8       19        1      active sync   /dev/sdb3
   2     2       8       35        2      active sync   /dev/sdc3
   3     3       0        0        3      faulty removed
   4     4       8       67        4      active sync   /dev/sde3
   5     5       8       83        5      active sync   /dev/sdf3
   6     6       8       99        6      active sync   /dev/sdg3
   7     7       8      115        7      active sync   /dev/sdh3

I contacted qnap support and here is what Pat Ho said:

Hi,

The disk 3 has lost its RAID table and caused NAS didn't recognize it.
And WD Green is not on our compatible list as well.
I could help to force assemble whole disks but it will lead 2 results. 1. data is back and safe. 2. forever lost data.

You can contact data recovery company if data really important to you. or send me Teamviewer ID and password for your own risk to recovery.

Best regards,
Pat Ho
QNAP Systems, Inc.

What do you think? I have a spare disk.

[pwilson]

Hello! i Have a TS-809 pro on firmware 3.2.7(been away from work for a year) running on RAID5 with 8 WD green disks(i know it's horrible).

would you take the risk on force rebbuild this array?

Code: Select all

[~] # mdadm -D /dev/md0
/dev/md0:
        Version : 00.90.03
  Creation Time : Tue Jun 22 23:42:20 2010
     Raid Level : raid5
  Used Dev Size : 1951945600 (1861.52 GiB 1998.79 GB)
   Raid Devices : 8
  Total Devices : 6
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Mon Sep 22 21:19:28 2014
          State : active, degraded, Not Started
 Active Devices : 6
Working Devices : 6
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : d979105e:1a1870af:e2b145e0:dadd82e0
         Events : 0.283476

    Number   Major   Minor   RaidDevice State
       0       8        3        0      active sync   /dev/sda3
       1       8       19        1      active sync   /dev/sdb3
       2       0        0        2      removed
       3       0        0        3      removed
       4       8       67        4      active sync   /dev/sde3
       5       8       83        5      active sync   /dev/sdf3
       6       8       99        6      active sync   /dev/sdg3
       7       8      115        7      active sync   /dev/sdh3
[~] # mdadm -E /dev/sdb3
/dev/sdb3:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : d979105e:1a1870af:e2b145e0:dadd82e0
  Creation Time : Tue Jun 22 23:42:20 2010
     Raid Level : raid5
  Used Dev Size : 1951945600 (1861.52 GiB 1998.79 GB)
     Array Size : 13663619200 (13030.64 GiB 13991.55 GB)
   Raid Devices : 8
  Total Devices : 7
Preferred Minor : 0

    Update Time : Mon Sep 22 21:19:28 2014
          State : clean
 Active Devices : 7
Working Devices : 7
 Failed Devices : 1
  Spare Devices : 0
       Checksum : 6eef567c - correct
         Events : 0.283476

         Layout : left-symmetric
     Chunk Size : 64K

      Number   Major   Minor   RaidDevice State
this     1       8       19        1      active sync   /dev/sdb3

   0     0       8        3        0      active sync   /dev/sda3
   1     1       8       19        1      active sync   /dev/sdb3
   2     2       8       35        2      active sync   /dev/sdc3
   3     3       0        0        3      faulty removed
   4     4       8       67        4      active sync   /dev/sde3
   5     5       8       83        5      active sync   /dev/sdf3
   6     6       8       99        6      active sync   /dev/sdg3
   7     7       8      115        7      active sync   /dev/sdh3

I contacted qnap support and here is what Pat Ho said:

Hi,

The disk 3 has lost its RAID table and caused NAS didn't recognize it.
And WD Green is not on our compatible list as well.
I could help to force assemble whole disks but it will lead 2 results. 1. data is back and safe. 2. forever lost data.

You can contact data recovery company if data really important to you. or send me Teamviewer ID and password for your own risk to recovery.

Best regards,
Pat Ho
QNAP Systems, Inc.

What do you think? I have a spare disk.

1. I would never put 8 drives in RAID5, (even with "recommended" drives).
2. RAID5 will only tolerate the loss of a "single" drive. You have lost two drives.
3. WD Greens are not certified/warranted for RAID use.
4. I maintain regular Backups of my NAS.
5. If that "spare" disk is another WD Green I would suggest that you do not use it with your NAS.

Whether you attempt to recover your data or not, is up to you. Can't you simply replace all 8 drives for "recommended" ones, and then restore your most recent Backup to the new array?

When you rebuild your NAS from scratch, I would recommend using only "recommended" drives, and I would further suggest that a single RAID6 array, or two RAID5 arrays with only 4 drives per volume would probably be far safer that your present setup. Perhaps you could purchase 4 drives for now, and set them up as a single RAID5 array and then you could restore your Backups to this Volume. You could then purchase an additional 4 drives later for that second RAID5 array.

If you don't have a usable Backup, then you might as well let QNAP Support attempt to recover your data. (You have nothing to lose that you haven't lost already).

[wat_up]

wow, i did not expect this grumpy reply!

First of all, i know the setup isn't even remotely a decent option. This Setup is not set up by me. I got this job after someone else and is trying to get back our precious customer video library.

I did not plan to use this setup again as we have invested in a much bigger and better solution for our needs involving Dell Powervault servers.

I am asking for opinions on whether this risk is worth to take, or should i go directly to a data rescue center and recover the files that we know are on the NAS?

i know i can't just replace all the disks and rebuild it to get the files on the old disks, i said i had a spare disk if it would help to replace the one disk that was faulty and then rebuild the array for extracting the files to a safe location.

[pwilson]

i know i can't just replace all the disks and rebuild it to get the files on the old disks, i said i had a spare disk if it would help to replace the one disk that was faulty and then rebuild the array for extracting the files to a safe location.

If you were talking about a "single" drive failure within a RAID5 array, "hot swapping" the drive with a "spare" results in a RAID rebuild as expected. Unfortunately in your situation you are suffering from "multiple drive failure", which is more than RAID5 can tolerate, hence your present RAID5 status.

As your RAID5 array is no longer viable, your data is only as safe as your last Backup. Whether you chose the present configuration or drives for that NAS is completely immaterial. No one is blaming anyone for anything here. We are simply working with the reality that you have suffered "multiple drive failure" regardless of who made these choices or when those choices were made.

Your present drives are not suitable for RAID use. Who or when those drives were chosen doesn't change this reality. You seem to feel that I'm "grumpy" but I assure you I am anything but grumpy. I'm sorry I told you something you didn't want to hear, but facts are facts. Why does it make me "grumpy" to provide the facts? Please shoot the message rather than the messenger. I didn't choose those drives either....

If you don't have current Backups, then I would urge you to contact the QNAP Helpdesk for further assistance. Perhaps they'll be able to manually rebuilt your array on the existing drives, in the hope that you can access the data long enough to make a backup now. Hopefully this won't result in you backing up too many corrupted files.