ZFS NVMe + VM (WS2019 + MSSQL 2016) = failed to create database


New Member
Sep 15, 2021

I'm trying to understand how to deal with this problem and i would be really grateful for any advice

So i'm installed Proxmox VE 7.1 on ZFS RAID 1, which was build by Proxmox itself during the installation. RAID contains two 960Gb NVMe SSD Samsung PM9A3. After install only setting that i'm manually changed regarding ZFS is "options zfs zfs_arc_max=8589934592". Everything else is configured by default.

Besides ZFS RAID 1 there is also hardware RAID 1 with two SATA SSD's. So i have two volumes, first is 1 TB ZFS RAID 1 (build on NVMe disks), second is 1 TB hardware RAID 1 (build on SATA disks)

Next i'm creating VM with Windows Server 2019 and with Microsoft SQL Server 2016 SP3. VM is stored on ZFS RAID 1. Here's full vm config just in case.

boot: order=virtio0;net0
cores: 8
cpu: host
machine: pc-i440fx-6.1
memory: 71680
meta: creation-qemu=6.1.0,ctime=1637648853
name: sv-sql2016
net0: virtio=C2:F4:EB:D7:89:77,bridge=vmbr1,tag=3
numa: 0
ostype: win10
scsihw: virtio-scsi-pci
smbios1: uuid=886d391b-df1a-4ae0-b43b-1b1761eb2736
sockets: 1
virtio0: local-zfs:vm-456-disk-0,backup=0,size=500G
virtio1: local-lvm:vm-456-disk-0,backup=0,size=500G
vmgenid: 047906de-2ffe-4ebe-93bd-d1cc9a4b8f71

virtio0 is volume stored on ZFS RAID 1 NVMe
virtio1 is volume stored on hardware RAID 1 SATA SSD

Next thing that i'm trying to do, is just create empty database in MSSQL 2016 and here is what i get.


Almost every time when i'm trying to create database, which will be stored on ZFS RAID 1, i'm getting error. But in 1 out of 10 try, it will create database without error.

So next thing i'm trying to do, is to move data folder to volume which is stored on hardware RAID, and it works without any problem there.

In result i don't understand how is this possible and what could be the problem, maybe i'm missing something? Maybe there are some options that should be configured for ZFS NVME RAID 1?

Machine specs, just in case:
Supermicro X11DDW-NT
Intel Xeon Gold 5222 CPU @ 3.80GHz

Edit: checked SMART on both disks and ZFS status, everything is fine. SMART is healthy on both NVMe disks and ZFS pool report zero errors
Last edited:


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