25.04 (Fangtooth) Development Notes

25.04 Fangtooth

This page tracks the latest development roadmap and notes for the future TrueNAS major version 25.04 (Fangtooth).

See the stable 24.10 (Electric Eel) release notes for information relating to that version.

For adventurous users that want to experiment with the latest feature development, 25.04 (Fangtooth) nightly images are available from the the TrueNAS downloads server.

More details are available from Software Releases.

TrueNAS^® | Enterprise™

Previous

Current

Next

TrueNAS 24.04 - Dragonfish

Latest:

24.04.2.5 Maintenance 8 November 2024

TrueNAS 24.10 - Electric Eel

Latest:

24.10.1 Maintenance 17 December 2024

---

Anticipated:

24.10.2 Maintenance 28 January 2025

TrueNAS 25.04 - Fangtooth

Latest:

25.04 Nightlies Experimental 13 August 2024

---

Anticipated:

25.04-BETA.1 Early 11 February 2025

25.04-RC.1 Early 11 March 2025

25.04.0 Stable 15 April 2025

• TrueNAS is an appliance built from specific Linux packages. Attempting to update TrueNAS with apt or methods other than the TrueNAS web interface can result in a nonfunctional system.

• All auxiliary parameters can experience changes between TrueNAS major versions due to security and development changes. We recommend removing all auxiliary parameters from TrueNAS configurations before upgrading as these settings can result in SMB share failures after an upgrade.

• After updating, clear the browser cache (CTRL+F5) before logging in to TrueNAS. This ensures stale data doesn’t interfere with loading the TrueNAS UI.

• The TrueNAS REST API is deprecated in TrueNAS 25.04 and replaced by the TrueNAS websocket client. Full removal of the REST API is planned for a future release.

  This new API Client is not the deprecated TrueNAS CLI (midcli). The API Client is integrated in TrueNAS 25.04 onwards. It provides the midclt command-line tool, and the means to easily communicate with middleware using Python to make calls through the websocket API.

  This API client allows for better integration of TrueNAS into third-party solutions. Use this as a reference for projects that require direct TrueNAS integration.

  TrueNAS API documentation remains available in the UI and through the TrueNAS Documentation Hub.

• The default libvirt account UID and GID is changed to to avoid possible clashes with user created Active Directory (AD) users. TrueNAS automatically updates libvirt UID and GIDs when upgraded to 25.04. Users attempting revert to 24.10 or an earlier release must manually review and update libvirt-qemu user and group IDs back to the values that were default in that version (64055:64055 for 24.10).

The chart below shows recommended paths for upgrading from earlier TrueNAS versions.

Update the system to the latest maintenance release of the installed major version before attempting to upgrade to a new major version.

Permitted upgrade methods are:

• update: apply an automatic update using the Update screen in the TrueNAS UI or install a manual update file. Some upgrade paths do not support these options (see chart).
• ISO install: save a current TrueNAS configuration file, perform a fresh install using an .iso file for the target version, and then upload the previously saved configuration.

Users can skip major versions with a fresh ISO install followed by a configuration file upload. Carefully review release notes for each skipped major version before upgrading, noting any service deprecations or significant changes that impact the previous configuration. Consider stopping at major versions with significant impacts to address changes before continuing the upgrade path or be prepared to manually reconfigure incompatibilities on the latest target version.

          flowchart LR
            A["11.3-U5"] -->|update| B["12.0-U8.1"]
            B -->|"update

ISO install"| C["13.0-U6.4

13.3-U1"]
            C -->|ISO install| H
            C -->|"(anticipated)"| I
            D["22.02.4 (Angelfish)"] -->|update| E
            E["22.12.4.2 (Bluefin)"] -->|update| F
            F["23.10.2 (Cobia)"] -->|update| G
            G["24.04.2.5 (Dragonfish)"] -->|update| H
            H["24.10.1 (Electric Eel)"] -->|"(anticipated)"| I
            I["25.04.0 (Fangtooth)"]
          

          flowchart LR
            A["11.3-U5"] -->|update| B
            B["12.0-U8.1"] -->|update| C
            C["13.0-U6.4"] -->|"(anticipated)"| F
            C["13.0-U6.4"] -->|"(anticipated)"| G
            D["23.10.2 (Cobia)"] -->|update| E
            E["24.04.2.5 (Dragonfish)"]  -->|"(anticipated)"| F
            F["24.10.1 (Electric Eel)"] -->|"(anticipated)"| G
            G["25.04.0 (Fangtooth)"]
          

Click the component version number to see the latest release notes for that component.

TrueNAS integrates many features provided by the upstream OpenZFS project. Any new feature flags introduced since the previous OpenZFS version that was integrated into TrueNAS (OpenZFS 2.2.99) are listed below:

For more details on feature flags, see OpenZFS Feature Flags and OpenZFS zpool-feature.7.

• The TrueNAS REST API is deprecated in TrueNAS 25.04 and replaced by the TrueNAS websocket client. Full removal of the REST API is planned for a future release.
• The default libvirt account UID & GID is changed to a less common value to avoid clashing with user created UID/GIDs. See Upgrade Notes above for more information (NAS-131695).
• Improved API key mechanism with support for user-linked API keys (NAS-131396). Existing API keys created via the TrueNAS API (not UI or TrueCommand) that specify an allow list with white-listed API methods are revoked upon upgrade because there is no clean way to migrate to the new system. Legacy API keys from TrueNAS 24.10 or earlier migrate to the root, admin, or truenas_admin account, depending on server configuration