Please see the following post in the TrueNAS forums
Install Home Assistant OS
Begin in the TrueNAS UI by adding a new ZVOL at least 32 GiB in size. Note the ZVOL path.
Then, using the TrueNAS shell, run these commands to (1) download, (2) extract, and (3) write the HAOS image for KVM to the ZVOL you created. In the 3rd command, replace tank/vm/haos with the path to your ZVOL. Notice the full ZVOL path should begin with /dev/zvol/ If you are logged in to your TrueNAS as the user root, you should omit sudo from the final command.
wget https://github.com/home-assistant/operating-system/releases/download/15.2/haos_ova-15.2.qcow2.xz
unxz haos_ova-15.2.qcow2.xz
sudo qemu-img convert -p -O raw haos_ova-15.2.qcow2 /dev/zvol/tank/vm/haos
Before moving on, please confirm that your Zvol Volume Size is at least 32 GiB. The Data Written may vary depending on the version of HAOS, but it should be around 586 MiB.
Creating a VM on TrueNAS 25.04
Click to Show
This section is a work in progress. You may find additional information and screenshots related to the new Instances in this thread, starting here
More information about Instances can be found here
Getting Started
In the TrueNAS UI, select Instances from the left-hand menu. If you have not already done so, click Configuration > Global Settings on the top right of the screen. Check the box to enable, then choose your pool. To keep things simple, this guide assumes that the Instances Default Network uses the default settings.
Show Getting Started
Import the ZVOL
Click Configuration > Manage Volumes on the top right of the screen. Next, click Import Zvols. Then select your Zvol and finally click Import.
Show Importing the Zvol
Create the Virtual Machine
Click Create New Instance on the top right of the screen.
Instance Configuration
Give your VM a name. Select VM for the Virtualization Method. Under VM Image Options, select “Upload ISO, import a zvol or use another volume”. Then click Select Volume. Finally, select the HAOS volume you imported.
CPU & Memory
Add at least two (2) cores under CPU Configuration and a minimum of 2 GiB for the Memory Size. If needed, these settings can be adjusted at a later time.
Storage
Leave these settings at the defaults. Note: The root disk is not used at this time and is a sparse volume. It will take up an insignificant amount of space.
Network
Uncheck “Use default network settings”. If you have created a bridge on TrueNAS, select the network bridge under Bridged Adapters. If you are not using a bridge, choose your network adapter under Macvlan NICs.
USB Devices
(Optional) USB devices can be added at a later time.
GPU Devices
(Optional) GPU devices can be added at a later time.
PCI Passthrough
(Optional) PCI devices can be added at a later time.
VNC
(Optional) VNC can be enabled at a later time.
Security
You do not need to select anything here.
Click Create
Show Create New Instance
More information about creating a VM in TrueNAS 25.04 can be found here
More information about installing HAOS in a VM can be found here
This guide is also posted in the TrueNAS forum and can be found here
Creating a VM on TrueNAS 24.10
Click to Show
Create the Virtual Machine
In the TrueNAS UI, select Virtualization from the left-hand menu, then click the add button to begin the Virtual Machine Creation Wizard.
Step 1 - Set the guest operating system to Linux, give your VM a name, and ensure UEFI is the selected boot method.
Step 2 - Assign 1 virtual CPU with at least 2 cores and a minimum of 2 GiB memory. Set the CPU mode to host passthrough.
Step 3 - Click use existing disk image and set the disk type to VirtIO. Select your existing HAOS ZVOL.
Step 4 - Choose a NIC for your VM. Set the adapter type to VirtIO. If you are not using a bridge, enable Trust Guest Filters to allow multicast.
Step 5 - Nothing is needed here.
Step 6 - Defaults should be fine.
Step 7 - Confirm options and save.
More information about creating a VM in TrueNAS Scale 24.10 can be found here
More information about installing HAOS in a VM can be found here
This guide is also posted in the TrueNAS forum and can be found here
Please see the 2nd post for troubleshooting common issues.
If you prefer running the TrueNAS App for Home Assistant, a setup guide can be found here
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