Ryfujk

The Volume on my Synology Expansion crashed and can't recover on its own.

Drive is probably OK. It happen after cleaning the device from dust. Until that time Volume
was also OK so I believe it isn't because of failed drive. When Starting up after cleaning, system dropped one disk and this is current state. What is weird it shows the Volume as CRASHED instead of DEGRADED.

Desktop Panel on Synology is showing that volume exists but Used space of 0 bytes and Available of 1 byte and it is not visible in Shared Folders.

I'm using Synology DS719+ (DSM 6.2-23739) with DX513 Expansion, which is populated with 5x 10TB IronWolfs having 1 Volume of SHR (1-drive failure tolerance, BTRFS) beyond separate volume, on two disks on main device (DS).

Storage Manager is showing that one drive is Not Initialized. I ran SMART and IronWolf Health Test on it and as far as tool is concerned the disk is fine.

Storage Manager log is showing that an I/O error has occured.

I found similar problem on a Synology Forum - [here][1]

As @voodooking* advised I run:

fdisk -l

cat /proc/mdstat



Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] 

md4 : active raid1 sdb7[2] sda7[1]

      4883750912 blocks super 1.2 [2/2] [UU]      

md3 : active raid1 sda6[3] sdb6[2]

      488366912 blocks super 1.2 [2/2] [UU]

md2 : active raid1 sdb5[2] sda5[3]

      483555456 blocks super 1.2 [2/2] [UU]

md6 : active raid5 sdca5[3] sdcd5[4] sdcc5[5] sdcb5[1]

      39046395904 blocks super 1.2 level 5, 64k chunk, algorithm 2 [5/4] [UUUU_]

md1 : active raid1 sda2[0] sdb2[1]

      2097088 blocks [2/2] [UU]      

md0 : active raid1 sda1[1] sdb1[0]

      2490176 blocks [2/2] [UU]

To find a problematic disk and match it by serial number from Storage Manager I ran:

hdparm -I /dev/sd???

mdadm --detail /dev/md6



/dev/md6:

        Version : 1.2

  Creation Time : Fri Sep  2 14:35:22 2016

     Raid Level : raid5

     Array Size : 39046395904 (37237.54 GiB 39983.51 GB)

  Used Dev Size : 9761598976 (9309.39 GiB 9995.88 GB)

   Raid Devices : 5

  Total Devices : 4

    Persistence : Superblock is persistent



    Update Time : Sun Mar  3 19:41:51 2019

          State : clean, degraded 

 Active Devices : 4

Working Devices : 4

 Failed Devices : 0

  Spare Devices : 0



         Layout : left-symmetric

     Chunk Size : 64K

            Name : Blade:6  (local to host Blade)

           UUID : 5c453f27:136ff82b:1b81964a:19d75973

         Events : 478796



    Number   Major   Minor   RaidDevice State

       3      68      229        0      active sync   /dev/sdca5

       1      68      245        1      active sync   /dev/sdcb5

       5      69        5        2      active sync   /dev/sdcc5

       4      69       21        3      active sync   /dev/sdcd5

       -       0        0        4      removed

and found that in my case not initialized partition is /dev/sdce5 so I ran:

mdadm --manage /dev/md6 --add /dev/sdce5

I check the status with:

cat /proc/mdstat







[>....................]  recovery =  0.0% (0/9761598976) finish=274544971.2min speed=0K/sec

And after about a minute or so it has ended (something went wrong). I run mdstat again and It was showing 5 drives but with (F) next to added drive. I rebooted and drive was still dropped from array and stay in not initialised state.

Storage Manager is showing Repair Option but with volume size of 1 bytes I don't know what will be the result of such repair (rebuild) - it will wipe out data from not initialised disk for sure, which maybe attached by some commands again without rebuild. Moreover such rebuild will take 10 days and It maybe not unnecessary extra strain on a drive.

Without this drive, SHR Volume with 1-drive failure tolerance, should work normally and be in DEGRADED state, so what can be wrong?

How to bring this Volume to Normal State?