4. What Software OS to choose?

4. What Software OS to choose?

When choosing the software for your NAS, there are many factors to consider and several options available. These choices will also influence the hardware you’ll need, but for simplicity, let’s focus on the most common DIY operating system choices used in home-lab and small-scale NAS builds.

Here’s a list of popular NAS Operating Systems, in no particular order:

1. TrueNAS (Scale or Core)
2. Unraid
3. OpenMediaVault (OMV)
4. Proxmox VE
5. Rockstor
6. CasaOS

TrueNAS

TrueNAS comes in two main editions: TrueNAS Core and TrueNAS Scale.
While they are both powerful and completely free, they are built on different operating systems:

• TrueNAS Core → based on FreeBSD
• TrueNAS Scale → based on Debian Linux

If the differences between FreeBSD and Linux are unfamiliar, feel free to look them up—but the general conclusion is:

• TrueNAS Scale offers more flexibility, broader modern application support, better virtualization options, and stronger long-term future-proofing.
• TrueNAS Core is known for being extremely stable, reliable, and perfect for traditional file storage—truly a “set-it-and-forget-it” NAS.

Both are free to use, though some optional third-party apps or enterprise features may require a subscription.

TrueNAS Scale

TrueNAS Scale is better suited for running Virtual Machines (VMs), Containers, and modern applications via Docker and Kubernetes.

• A Virtual Machine (VM) creates a fully isolated environment on your server that runs its own full operating system. For example, your NAS might run Linux while a VM runs Windows inside it at the same time.
• A Container is lighter and doesn’t include its own OS. Instead, it shares the host system’s kernel and runs individual applications—great for things like media servers, Nextcloud, databases, or office suites.

Because of this flexibility, users who want to self-host apps and experiment with more modern setups often choose Scale.

TrueNAS Core

TrueNAS Core focuses on traditional NAS functions and prioritises stability. It is widely considered “bulletproof” for storing and managing data.

If your main goal is reliability rather than running lots of apps, Core is a great choice. Still, everyone has their own opinion—do your own research and choose the option that best fits your needs. That’s the beauty of DIY.

Why I Chose TrueNAS: OpenZFS

One of TrueNAS’s biggest strengths is its use of OpenZFS, an advanced file system designed for data integrity, redundancy, and long-term reliability.

With OpenZFS, you create a ZFS Pool—a group of drives working together. Within that pool, you can create RAIDZ configurations:

• RAIDZ1 → Allows 1 drive to fail without losing data.
• RAIDZ2 → Allows 2 drives to fail, offering much stronger protection.
• RAIDZ3 → (Less common for home users) Allows 3 drives to fail.

For example:
If you create a RAIDZ1 pool with 5 drives, the capacity of 4 drives is available for storage, and 1 drive is reserved for redundancy. If a single drive fails, you replace it and ZFS automatically rebuilds the data.

I personally prefer RAIDZ2 because having two drives of redundancy significantly reduces the risk of data loss—especially during a rebuild, which is when drives are under the most stress.

With TrueNAS Scale, ZFS continuously checks and corrects data inconsistencies through a process called scrubbing, helping keep your data error-free.

Final Thoughts

In short:
OpenZFS + TrueNAS = extremely strong data protection.
It isn’t perfect—nothing is—but it is one of the most reliable options available for DIY NAS builders.

Unraid

Unraid takes a completely different approach compared to other NAS operating systems, and it excels when using many different-sized HDDs. Instead of requiring identical drives or traditional RAID, Unraid simply adds drives into your array as you need them. This makes it especially popular for users who expand storage slowly over time.

Unraid uses a single or dual parity drive to protect your data. This is somewhat similar to RAID4, but without striping. Each data drive is independent, meaning:

• If one drive fails (in single-parity mode), Unraid can rebuild it using parity.
• If two drives fail (in dual-parity mode), it can still rebuild.
• Each drive’s data is stored individually, making recovery simple.

If these concepts are unfamiliar, just know that it’s another effective way to keep your data safe when a hard drive fails.
Unraid also supports ZFS, but only through an add-on—it is not built-in like TrueNAS.

Lightweight and Low Resource Usage

One of Unraid’s biggest strengths is how lightweight it is. It uses very little CPU and RAM, which makes it perfect for older or low-power hardware. Despite being lightweight, Unraid offers an enormous ecosystem of Docker containers, plugins, and community apps you can install easily from third-party repositories.

A unique aspect of Unraid is that it runs entirely from a USB flash drive rather than a hard drive or SSD. You simply configure your motherboard’s BIOS to boot from the USB stick. All your array and application data still lives on your HDDs or SSDs.

Licensing

Unraid requires a one-time payment, and many users consider it absolutely worth it for the flexibility, ease of use, and massive software support. While TrueNAS leans toward enterprise-grade storage, Unraid is designed with home users and enthusiasts in mind, offering a very friendly and flexible approach to storage expansion and application hosting.

OpenMediaVault (OMV)

OpenMediaVault (OMV) is a beginner-friendly, Debian-based Linux operating system designed specifically for NAS setups. It is one of the most accessible options for new users because of its clean and simple web interface, light system requirements, and modular design.

OMV is extremely lightweight and can run on very basic or older hardware, making it ideal for budget builds, low-power systems, and smaller home servers.

Storage Features

Out of the box, OMV supports software RAID using mdadm—a mature and reliable Linux RAID system. This allows you to create RAID levels such as:

• RAID 0
• RAID 1
• RAID 5
• RAID 6
• RAID 10

While RAID via mdadm is not as advanced as OpenZFS, it is simple, stable, and perfect for users who just need straightforward redundancy.

OMV also supports ZFS, but it requires a plugin. Once installed, you can create ZFS pools, use ZFS snapshots, scrubs, and benefit from its advanced data integrity features.

Plugins, Docker, and Expandability

One of OMV’s biggest strengths is its extensibility. Through its plugin system, users can easily add:

• Docker
• Portainer
• Compose management
• Cloud services (e.g., Nextcloud)
• Media servers (e.g., Jellyfin, Plex)
• Backup tools
• Monitoring tools

Because OMV is built on Debian, anything that runs on Debian can be installed and managed—either through plugins or manually if you prefer.

This means OMV can remain lightweight for simple file sharing, or be expanded into a full home server running multiple applications and services.

User Experience

OMV is well-loved for its ease of use:

• Clean and simple web dashboard
• Straightforward management of users, shares, disks, and services
• Great documentation and large community
• Minimal system overhead
• Reliable updates from the Debian ecosystem

It strikes a balance between simplicity and power—excellent for beginners, but still capable of running more resource-heavy apps when needed.

Proxmox

I absolutely love Proxmox. When I first installed it and realised what it could do—and how much it could do—I knew I had discovered something incredible.

Proxmox Virtual Environment (Proxmox VE) is an enterprise-grade hypervisor, built on Debian Linux, and designed to run Virtual Machines (VMs) and Containers with impressive performance and flexibility. Once you understand its capabilities, it becomes the backbone of an extremely powerful home lab or NAS setup.

What Is Proxmox?

Proxmox VE is a Type-1 hypervisor, which means it runs directly on your hardware and manages virtual machines without needing another operating system underneath. As a result, it’s fast, efficient, and extremely reliable.

With Proxmox, you can run:

• Multiple operating systems
• Multiple NAS platforms (TrueNAS Scale, TrueNAS Core, OMV, Unraid in a VM)
• Multiple applications
• LXC containers (lightweight and efficient)
• Docker (via containers or a VM)

All on a single server.

Because of this flexibility, many home lab builders and IT professionals run their entire environment on Proxmox—from firewalls to NAS systems, media servers, cloud services, and more.

Why Proxmox Is So Popular

1. Low Hardware Requirements

Despite being enterprise-level, Proxmox can run on almost anything—from small Intel NUC-style builds to full rack servers. It scales from a simple home NAS to a multi-node cluster.

2. Powerful VM and Container Support

Proxmox lets you run:

• KVM Virtual Machines (full operating systems like Windows, Linux, BSD)
• LXC Containers (lightweight environments for apps or services)

This means you can isolate different tasks for better performance, stability, and security.

3. Web-Based Management

Once installed, you manage everything through a clean web interface (GUI).
You can:

• Create and delete VMs
• Allocate CPU, RAM, and storage
• Attach virtual drives
• Configure backups
• Monitor performance
• Manage disks and storage pools

All from your browser.

4. Enterprise Features

Even though Proxmox is free to use, it includes features you’d normally only find in paid hypervisors:

• Live migration
• Snapshots and backups
• ZFS storage support
• Clustering multiple nodes
• High availability (HA)
• Firewall and network management

For home users, this provides insane value.

How It Fits Into Your NAS Setup

With Proxmox, you can run all the NAS operating systems mentioned earlier—TrueNAS Scale, TrueNAS Core, OpenMediaVault, and even Unraid (though Unraid inside a VM is experimental).

This would be overkill for most people, but a lot of NAS enthusiasts enjoy comparing them side-by-side or switching between them easily.

More realistically, Proxmox becomes the “host” and your NAS (e.g., TrueNAS Scale) becomes a guest VM. This allows you to:

• Move or change NAS software later
• Take snapshots of your NAS VM
• Restore from backups instantly
• Add more services without cluttering the NAS OS
• Run multiple workloads on one machine

For anyone wanting to learn virtualization, networking, or self-hosting, Proxmox is hands-down one of the best platforms to start with.

Learning Curve

Proxmox does have a learning curve, especially around:

• Virtual networking
• Storage passthrough
• PCIe/VFIO passthrough
• Firewall configurations
• ZFS and disk management

But the more you work with it, the more you learn—and the more powerful your setup becomes.

If you want to go deeper into computing, virtualization, and advanced NAS setups, I highly recommend giving Proxmox a real try.

FINALLY: Rockstor and CasaOS

You also have Rockstor and CasaOS as NAS operating system choices. While they are less common than the big names like TrueNAS, Unraid, or OpenMediaVault, they each offer unique features that might suit your needs perfectly.

Even though I haven’t used these personally, I’ll share the essential information so you understand what they are and how they compare. Later, you may want to install them on Proxmox and share your findings with the NAS community. One day I’ll test them as well—but for now, I think we already have plenty on our plates!

Rockstor

Rockstor is an open-source NAS operating system built on Linux and powered by the Btrfs file system (pronounced “Butter-F-S”). This makes Rockstor a great option for users who want strong data integrity without diving into ZFS.

Key Features

• Btrfs-based Storage:
  Rockstor uses Btrfs for snapshots, pooling, compression, and bitrot protection. While Btrfs isn’t quite as mature as OpenZFS, it’s simpler and lighter for small home NAS setups.
• Docker Integration:
  Rockstor includes the Rock-ons system, which allows users to easily install and run Docker-based apps such as Plex, Nextcloud, or Transmission.
• Clean Web UI:
  The interface is modern, simple, and easy for beginners to navigate.
• Low System Requirements:
  Rockstor is lightweight and can run on very modest hardware, especially compared to ZFS-based systems.
• Active Development:
  While the community is smaller, development is ongoing and focused.

Who Rockstor Is For

• Users who want simple, modern storage management
• Builders who prefer Btrfs instead of ZFS
• People who want Docker apps without manually configuring containers
• Anyone with low-power or older hardware

Rockstor is a strong but lesser-known option for users who want a lightweight NAS OS with a modern foundation.

CasaOS

CasaOS is a newer, modern, beautifully designed home server operating system built with beginners in mind. It focuses heavily on simplicity, apps, and a clean, intuitive experience.

Key Features

• App Store–Style Experience:
  CasaOS comes with a polished App Store offering common apps such as Jellyfin, Nextcloud, qBittorrent, Home Assistant, Portainer, and many more. Installing apps is almost as easy as clicking “Install.”
• Docker-Based Architecture:
  Everything runs on Docker, so the system is extremely flexible and supports thousands of applications.
• Beginner-Friendly UI:
  The dashboard looks like a modern smartphone or tablet interface—ideal for new users or anyone wanting a visually pleasing experience.
• Lightweight:
  CasaOS runs well on small single-board computers (SBCs) like the Raspberry Pi, mini PCs, and low-power NUC-style systems.

Who CasaOS Is For

• Users who want the simplest possible NAS/home server experience
• People who love a clean, modern UI
• Builders using mini PCs, SBCs, or older systems
• Anyone who wants a Docker-heavy home lab with minimal configuration

CasaOS isn’t as advanced for storage as TrueNAS or Unraid, but it shines as a smart home server for apps, media, and convenience.

Other Options

One more thing worth mentioning is that you can also build a NAS directly on Windows, Linux, or a mainstream distro like Ubuntu. These can handle file sharing, Docker apps, and even RAID, but they require more manual setup and lack the polished NAS dashboards that dedicated NAS systems offer.

What’s Next

For all the NAS operating systems discussed, I’ll soon include a side-by-side comparison. This will help you clearly see the differences between:

• TrueNAS Core
• TrueNAS Scale
• Unraid
• OpenMediaVault
• Proxmox VE
• Rockstor
• CasaOS

As mentioned in the NAS Info section of the website, I’ll also continue to share the research I’ve gathered so far. This comparison should make it much easier for you to choose the path that best suits your needs.

Core Philosophy: Hypervisor vs. NAS OS
The most critical distinction is between Proxmox, which is fundamentally a bare-metal hypervisor, and the other three, which are NAS (Network-Attached Storage) operating systems. 

Proxmox VE: A hypervisor designed to run many different virtual machines (VMs) and containers (LXC) efficiently on one machine. Storage and file sharing are secondary functions that require more advanced configuration.
TrueNAS SCALE, Unraid, OMV: These are storage-first platforms, designed to easily manage hard drives, create redundant arrays, and share files across a network via protocols like SMB, NFS, and iSCSI. They have added virtualization features as secondary functions.

• Choose TrueNAS SCALE if:
  • Data integrity is paramount and you require enterprise-grade features like ZFS data protection, snapshots, and iSCSI block storage.
  • You have a powerful server with matched drives and are willing to manage the complexity of ZFS and its stricter RAM requirements.
  • You want integrated Docker/Kubernetes application management alongside powerful storage management.
• Choose Unraid if:
  • Hardware flexibility is key, and you want to use a mix of different sized drives and easily expand your storage array over time.
  • You are building a home media server (Plex, Jellyfin) and want excellent, user-friendly Docker and VM support.
  • You are comfortable paying a one-time license fee for ease of use and flexibility.
• Choose OpenMediaVault if:
  • Budget and minimal hardware are constraints (e.g., using a Raspberry Pi or an old PC).
  • You primarily need basic, reliable file sharing (SMB/NFS) and are comfortable adding specific features via plugins or the command line interface (CLI).
  • You want a completely free, open-source solution based on stable Debian Linux.
• Choose Proxmox VE if:
  • Your primary goal is virtualization and running multiple services as isolated VMs and containers (homelab environment).
  • You may run a NAS system (like OMV or TrueNAS) as a virtual machine within Proxmox using disk pass-through.
  • Clustering multiple servers together for high availability is a desired feature.

This overview just scratches the surface, but it should make the decision-making process much easier.

In the next post, I will dive into the software I’ve chosen and explain why it’s the best fit for my NAS setup.