TrueNAS 25.04, codenamed “Fangtooth,” was recently released (download here), and with it comes a full embrace of Linux as the underlying base. While previous versions of TrueNAS were confusingly split between CORE (built on FreeBSD) and SCALE (built on Linux), this release finally pushes the project further into its beautiful Linux future.
This version builds on the foundation laid by TrueNAS 24.10 “Electric Eel.” That version brought improved performance and Docker support, and Fangtooth expands on it with more than 1,000 changes, including over 150 bug fixes. The update is being offered as a release version, but iXsystems is still recommending it for early adopters only — at least for now.
TrueNAS 25.04 runs on Linux Kernel 6.12, which brings broader hardware support and more flexibility overall. One major feature is Fast Deduplication, which is especially helpful for all-NVMe systems like the H30 and F100. It can help reduce the storage footprint in certain workloads, particularly in virtualized environments. RAID-Z expansion is also faster now which could be helpful for those managing growing pools of data.
There are updates to virtualization as well. LXC and QEMU/KVM are now handled via Incus, offering an alternative to jails and an improved VM system. Secure Boot is also supported in this release, which is useful for operating systems that require TPM. The virtualization changes are still marked experimental, but they show where TrueNAS is headed.
App management also improves with the ability to assign IP addresses to new apps, and existing apps will get this capability by June 1. Users still running version 24.04 are encouraged to update soon to take advantage of the new app migration system.
For enterprise users, TrueNAS 25.04 brings a number of enhancements. Security improvements include support for GPOS STIG configurations, which may appeal to organizations with stricter compliance needs. Performance also gets a boost with RDMA support for iSCSI and NFS, as well as block-level cloning for VMware workloads.
Fibre Channel support is now included too, giving administrators more storage protocol options on the same hardware. There’s also faster SMB file copy performance and easier file recovery via snapshot directory access over NFS.
Before upgrading, TrueCommand users should first move to version 3.1 to maintain compatibility with Fangtooth. As for which version to run, TrueNAS 24.10.2.1 is still the safer choice for production environments right now. However, 25.04 is an option for users who want to test the new features or are deploying new systems. For those coming from CORE 13.x, this version offers a direct path forward, with familiar NAS features like SMB, NFS, and iSCSI preserved while adding access to Docker and LXC.
As TrueNAS continues to evolve and improve, the division between CORE and SCALE appears to be fading. With 25.04, Linux is now the foundation, and the project is clearly steering in that direction going forward.
