WS5420RN6 RAID 5 Initialization Disk taking very long time

[sva]

Hello, I've bought a WS5420RN6 Series which has 4 8TB drives installed.
Setup was done from the provided USB stick (Japanese WSS 2016), which I converted to English. And once prepared, I kicked off the RAID 5 build using the Buffalo provided tool - RAID Builder, however 4 days later, it still hasn't finished.

Disk Management Tool shows the drives as being in a "Resynching" State,  NAS Navigator shows the Notice: "I18:Rebuilding drive D...(2023/06/13 00:59:51)

For the RAID drive, Task Manager shows a Read Speed of  13MB/s and Write of 4MB/s which doesn't sound right - the drives are supposed to operate at up to 200MB/s.
Any idea what could possibly be wrong ?

[davo]

I'd test the disk individually, there's probably errors on at least one of them.

[sva]

I did that before building the array, testing each drive using CrystalDisk on a PC and all appeared to be clean - in particular no C6 errors reported at all on any of the disks. Even installed it upon the box itself, and all drives are reported as being Good, and operating with SATA/600 mode.

I'm wondering if it's a RAID controller issue - but how can I determine that - I can stop the rebuild and go back to start or I can leave it, though the disk transfer rate seems quite poor and if the Write speed is anything to go by, another full 2 months of online rebuilding would be required.... which does not make sense.

Additionally No Errors are reported in the Windows Event Viewer.


Any thoughts ?


PS. I downloaded Crystal Disk Mark, and ran it on the C drive - the same drive hosts part of the RAID 5 array. The results were:

All   5  1GiB  C: 21% (21/100GiB) (M/s)

               Read (MB/s)          Write (MB/s)
SEQ1M    223.35                   216.63
QBT1

SEQ1M       44.04                 184.34
Q1T1

RND4K         3.04                   2.25
Q32T1

RND4K         0.39                   1.73
Q1T1

[davo]

It's a software RAID controller not hardware so doubt it's that. If it was then reinstalling the OS might fix it but you said it was freshly installed?

[1000001101000]

Suppose you could try installing linux on the thing to compare performance under a different software RAID implementation. 

[sva]

It's been a nail-biting experience- do I ride it out and for how long, or do I cancel and ditch the whole thing... amazingly this morning, it's finished!!!! 5 days later! Disk Management reports each partition of the 4 drive RAID-5 volume as being Healthy! Though the front panel of the device still reports "Drive D" as being in a "Rebuilding" state !?!?


As the Windows Storage Server lives on the 1st drive by default, I've added a mirror of it onto the 2nd drive, and for good measure in this 8GB machine, have added a stripped 100GB drive across 2 of the other drives for paging space. One thing I noticed, was that during creation of these, the Write speed rocketed up to over 110MB/s.


Using a rough calculation - the RAID-5 build for this device worked out at somewhere between 61-65 MB/s across all drives, so when reading the Task Manager display, it seems that I needed to take (Read + Write speed) per drive, and multiply by the number of Drives in order to determine completion time.


So after all that, here's what my Disk Management tool tells me now:

Disk 0 ::    100MB  / Healthy (EFI System Partition)   |    (C:)  / 100GB NTFS / Healthy (Boot, Page File, Crash Dump) | (D:) / 7351 GB ReFS / (Healthy) | 50 MB / Unallocated
Disk 1 ::   (D:) / 7351.76 GB ReFS / Healthy | (C:) / 100GB NTFS / Healthy (Boot, Page File, Crash Dump) |  150 MB / Unallocated
Disk 2 ::   (D:) / 7351.76 GB ReFS / Healthy | New Volume (E:) / 100.15 GB NTFS / Healthy
Disk 3 ::   (D:) / 7351.76 GB ReFS / Healthy | New Volume (E:) / 100.15 GB NTFS / Healthy