Why Choose Unraid for VMs Over Proxmox or ESXi?
I once operated a homelab running Proxmox VE with over 12 VMs and containers. It was a great environment for sandboxing before production. However, when my needs shifted toward large-scale storage combined with running Windows VMs for video editing or gaming, Unraid proved superior thanks to its flexibility.
Proxmox focuses purely on virtualization. In contrast, Unraid allows you to mix and match hard drives of different capacities into a single storage array. This system still integrates KVM for extremely smooth VM performance. Unraid’s biggest advantage is Hardware Passthrough. Passing a GPU, network card, or USB controller directly into a VM is done right through the web interface without needing complex commands.
Quick Start: Setting Up Your First VM
Before you begin, ensure you have enabled VT-x/AMD-V and IOMMU in your BIOS. These are prerequisites for stable virtualization.
- Enable VM Manager: Go to Settings > VM Manager. Set Enable VMs to Yes and click Apply.
- Prepare ISO: Download installation files (Windows, Ubuntu…) into the
isosfolder on Unraid. - Initialization: In the VMs tab, select Add VM and click on the corresponding OS icon.
- Setup: Choose the number of CPU cores, RAM capacity, and point the path to your ISO file.
- Completion: Click Create at the bottom of the page. The VM will start, and you can control it via VNC directly in your browser.
Optimizing Settings for Peak Performance
1. CPU Pinning – Intelligent Core Allocation
Many beginners often leave the default settings where the VM shares all CPU cores with the OS. When the VM handles heavy tasks, the entire NAS can stutter.
The golden rule: Always set aside Core 0 and its hyper-threading (HT) sibling for Unraid. For example, with an i5-12400 CPU (6 cores/12 threads), I would reserve Core 0 and Core 6 for the system. Only assign the remaining cores to the VM. This ensures that parity sync or disk writes are not interrupted, preventing lag when watching movies or accessing files.
2. RAM: Avoid Dynamic Mode
The RAM configuration interface has two fields: Initial Memory and Max Memory. I recommend entering the same value for both. Allowing KVM to automatically scale RAM (Ballooning) frequently causes Blue Screen of Death (BSOD) errors or system hangs on Windows 10/11.
3. VirtIO Drivers – The “Grease” for Your System
Without VirtIO drivers, Windows won’t see the virtual hard drive or recognize the network card. Unraid has a built-in button to download the VirtIO ISO in the configuration menu. Choose the latest version to achieve 10Gbps network speeds and optimal disk read/write performance.
Advanced: Turning Your VM into a Gaming PC with GPU Passthrough
You can turn Unraid into a home Cloud Gaming rig by passing a graphics card directly to a VM. In this mode, the VM achieves nearly 100% of physical machine performance.
Device Isolation (VFIO-PCI)
You need to prevent Unraid from grabbing the GPU at boot. Go to Tools > System Devices, check the GPU and its associated Audio controller, then select Bind selected to VFIO at boot and restart.
If you encounter errors where software fails to recognize the card because it’s running in a virtualized environment, you’ll need a minor XML tweak. Look for the <kvm> block and add the hidden state='on' line to “cloak” the VM from anti-cheat systems:
<features>
<hyperv>
<vendor_id state='on' value='1234567890ab'/>
</hyperv>
<kvm>
<hidden state='on'/>
</kvm>
</features>Real-World Experience to Avoid “Heartache”
Always Place vDisks on an SSD Cache
Never store your VM hard drive files (.img) on the traditional HDD array. The random read/write speed of HDDs is very low, making Windows take minutes to boot. When placed on an NVMe SSD, Windows only takes about 8-12 seconds to reach the home screen. The difference is massive.
Backup Strategy
Unraid lacks a quick Snapshot feature like Proxmox. To be safe, install the VM Backup plugin from Community Applications. I usually schedule backups of XML configs and vDisks at 2 AM every Sunday. If a VM breaks after some tinkering, it only takes 5 minutes to restore it to its previous state.
Handling a Frozen VM
Sometimes the web interface freezes, and you can’t shut down the VM. In this case, SSH into Unraid and use the command line for help:
# View list of running VMs
virsh list --all
# Force shutdown (similar to pulling the plug)
virsh destroy "VM_Name"Conclusion
Unraid might not be as enterprise-grade as ESXi, but it is the #1 choice for individual users wanting an “all-in-one” device. Combining a storage NAS and a workstation VM on the same hardware significantly saves on electricity and room space. Try repurposing your old PC; the feeling of building a versatile server yourself is truly rewarding!
