One of the best aspects of building your own NAS is the sheer number of operating systems you can choose from. Among them, TrueNAS Scale and Unraid lie at the top of the food chain thanks to a multitude of features implemented specifically for NAS workloads.

While they’re fantastic in their own rights, both operating systems have their fair share of pros and cons. But as a home lab fanatic who has experimented with TrueNAS Scale and Unraid on multiple occasions, here are five reasons why I’m fond of the former.

5 Better performance

In virtualization tasks as well as transfer speeds

Unless you’re running a full-fledged Proxmox server, most NAS systems are great for self-hosting your favorite services. However, TrueNAS Scale provides a more responsive experience when you wish to deploy multiple virtual machines and containers on your NAS. Plus, the transfer speeds continue to scale once you start looking into complex RAID setups for your TrueNAS-powered storage server. And while we’re on the subject of RAID…

4 Superior RAID provisions

To be fair, the OS is called Unraid

True to its name, Unraid doesn’t support conventional RAID configurations. While it’s a bit of an oversimplification, Unraid lets you create JBOD (Just a Bunch Of Disks) setups featuring the parity facility for some extra resilience. As such, it’s more akin to a RAID 4 setup – except you don’t get the faster speeds due to the absence of striping provisions.

In contrast, TrueNAS Scale supports multiple RAID configurations. From simple mirror and RAIDZ setups to the more complicated dRAID arrangements, TrueNAS Scale is great when you want to leverage multiple drives in your NAS.

3 Built-in iSCSI support

Perfect for gaming on a NAS

On paper, iSCSI isn't as versatile as SMB, as you can access your storage from only one device. However, it’s a fantastic protocol when you need to mount a NAS drive as local volume on your PC. When I tried to store Steam games on my NAS back in July, setting up block storage using iSCSI provided a highly responsive experience – even in fast-paced titles.

While the games took a tad too long to load from an HDD, using an NVMe SSD over the iSCSI protocol resulted in surprisingly decent fast-travel and loading times. Unlike TrueNAS, Unraid doesn’t feature support for iSCSI shares, meaning you’ll have to look into third-party plugins to use this protocol in your NAS setup.

2 You're not limited to USB flash drives

No more license-migration issues

Whereas TrueNAS can be set up on most storage drives, Unraid requires you to flash the contents of the OS onto a pen drive. Sure, a high-quality flash drive will last a long time, but you’ll be in a world of trouble in case it fails unexpectedly. Since the operating system’s license is tied to the GUID of the USB device, you’ll have to request Unraid to transfer the existing license over to a new flash drive to gain access to your storage server.

1 It's free to use

You don't have to pay a dime for the software

By now, you must have realized that you need a paid license for your Unraid server. While TrueNAS also has a paid Enterprise edition featuring professional-tier virtualization and security features, the free Scale variant includes all the features you can ever need for a home-based NAS.

In contrast, Unraid requires you to pay a minimum of $49 at the end of the free 30-day trial period. Plus, you’ll also need to renew the license for $36 every year if you want to keep receiving software updates, or invest $249 on a Lifetime Access license. When you’re building a NAS on a budget, it’s a good idea to minimize your expenses using TrueNAS Scale.

All that said, Unraid is still a top-tier OS

Despite favoring TrueNAS over Unraid, I’d be lying if I said the latter is a terrible operating system for a NAS. Heck, there are plenty of aspects where Unraid leaves its rival in the dust. Compared to TrueNAS’ ZFS-only restriction, Unraid supports most of the NAS-centric file systems, including Btrfs, XFS, and ReiserFS. Besides a simpler UI, Unraid lets you shrink pools, and you can mix drives of different capacities in your storage array rather than sticking to the same size for the advanced RAID configurations of TrueNAS.

But if you’re not a fan of dedicated NAS operating systems, you can set up makeshift storage servers using Windows 11, Ubuntu, Debian, and other conventional desktop operating systems.