Disk passthrough is essential if you want TrueNAS to fully control physical disks and ZFS features.
In this tutorial, you’ll learn how to passthrough physical SATA or SSD disks from Proxmox to TrueNAS step by step.
We explain the difference between raw disk passthrough vs virtual disks and why it matters.
This guide covers by-id disk mapping, Proxmox CLI commands, and VM configuration best practices.
You’ll also learn how to verify SMART data, disk serial numbers, and temperature inside TrueNAS.
Common mistakes that cause missing SMART, unstable pools, or data loss are clearly explained.
The tutorial works for Proxmox VE with TrueNAS SCALE or CORE.
By the end, you’ll have a stable, production-ready TrueNAS storage setup on Proxmox.

STEP 1: Identify the disk on the Proxmox host

Get the disk name
SSH to Proxmox
lsblk
You will see the following:
sda 240G (system disk)
sdb 240G (newly mounted disk)
Remember the disk name (e.g., sdb)

Get the disk ID
ls -l /dev/disk/by-id/

Example:
ata-KINGSTON_SA400S37240G_50026B76841096E3

Copy this line exactly
DO NOT use /dev/sdb (easily reversed)
If the disk CONTAINS DATA – you want to FORMAT
Be careful – formatting will erase all data

Method 1: Erase the partition + signature

(RECOMMENDED)
wipefs -a /dev/disk/by-id/ata-XXXX
Or more drastic:
sgdisk –zap-all /dev/disk/by-id/ata-KINGSTON_SA400S37240G_50026B76841096E3
TrueNAS prefers this type of “clean” disk.

Method 2: Using dd (only when disk is corrupted)

dd if=/dev/zero of=/dev/disk/by-id/ata-XXXX bs=1M count=100
Only write the first 100MB, enough to erase old metadata.

STEP 2: Assign disk to TrueNAS VM

Assuming:
• TrueNAS VM ID = 108
• Disk ID:
ata-KINGSTON_SA400S37240G_50026B76841096E3

Run the command:
qm set 108 -scsi3 /dev/disk/by-id/ata-KINGSTON_SA400S37240G_50026B76841096E3
scsi3 = 4th disk

STEP 3: Set the correct controller

Open VM → Hardware
• SCSI Controller: VirtIO SCSI single
• Cache: None
• IO Thread: off

STEP 4: Start TrueNAS VM

qm start 108

Go to TrueNAS Web UI → Storage

STEP 5: Create a Pool in TrueNAS

1. Storage → Pools → Add
2. Select the 240Gb disk
3. Create Pool
The disk will appear as a real disk, not a virtual disk