This PR adds test support for label, object, delay and panic error injection modes in the ZTS testing suite. It also contains negative tests verifying the function arguments. A new zinject_counter function is used as a helper to identify if delay, panic error modes are executed in the test.
This is a guide of the steps I followed to downgrade from TrueNAS 26 MASTER to TrueNAS 26 BETA1. (specifically from 26.0.0-MASTER+20260405-020459 to 26.0.0-BETA.1)
TrueNAS considers MASTER a higher train than BETA. Attempting a manual update from MASTER to BETA.1 gives:
Unable to downgrade from 26.0.0-MASTER+20260405-020459 to 26.0.0-BETA.1
Step 1: Bypass the Downgrade Check
Step 2: Fix the Alembic Migration Mismatch
You need to find BETA.1’s head migration revision. Mount the .update file on another Linux machine:
sudo mkdir -p /tmp/truenas-beta
sudo mount -t squashfs -o ro,loop TrueNAS-26.0.0-BETA.1.update /tmp/truenas-beta
sudo mkdir -p /tmp/truenas-rootfs
sudo mount -t squashfs -o ro,loop /tmp/truenas-beta/rootfs.squashfs /tmp/truenas-rootfs
Find the last migration file and its revision ID:
ls /tmp/truenas-rootfs/usr/lib/python3/dist-packages/middlewared/alembic/versions/26.0/
grep “^revision” /tmp/truenas-rootfs/…/last_migration_file.py
Then on TrueNAS, stamp the database with that revision:
sudo sqlite3 /data/freenas-v1.db “UPDATE alembic_version SET version_num=”;”
Step 3: Apply the Update
DISCLAIMER: Keep a backup of your settings!!!!
Happy to contribute not only to TrueNAS but also to OpenZFS upstream !!
The official announcement from iXsystems: https://www.truenas.com/blog/blog-truenas-26-beta1-release/
https://www.phoronix.com/news/TrueNAS-26-Beta
Download the BETA iso from here: https://download.truenas.com/TrueNAS-26-BETA/26.0.0-BETA.1/TrueNAS-26.0.0-BETA.1.iso
The .update file version is available here: https://update-public.sys.truenas.net/TrueNAS-26-BETA/TrueNAS-26.0.0-BETA.1.update
Officially an OpenZFS contributor 🙂
https://github.com/openzfs/zfs/commit/a7157221db1d3a7c3517dee98f5124c13a515053
Running TrueNAS in VirtualBox is a great way to test configurations, experiment with ZFS pools, or learn the TrueNAS UI before deploying on real hardware. As of February 2026, the latest stable version is TrueNAS 25.10.2.1 (Goldeye), with TrueNAS 26 beta planned for April 2026.
Under System > Processor, make sure to enable PAE/NX. Under System > Acceleration, enable VT-x/AMD-V and Nested Paging.
For the disk controller, use AHCI (not IDE) for better performance and compatibility.
Note: If you’re on an AMD system and get a VERR_SVM_IN_USE error, you may need to unload the KVM modules first — see my post on VirtualBox AMD-V fix.
Once TrueNAS boots, it will display the web UI address on the console. Open it in your browser and create your ZFS pool using the additional virtual disks.
This setup is perfect for testing pool configurations, snapshots, replication, and apps before committing to production hardware.
The latest episode of TrueNAS Tech Talk (T3) — Episode 56 — dropped on March 6, 2026, and it’s packed with news that every TrueNAS homelab enthusiast and sysadmin will want to hear. Hosts Kris Moore and Chris Peredun (the TrueNAS HoneyBadger) cover the upcoming TrueNAS 26 release schedule, a deep dive into the new dataset tiering feature, and tackle eight viewer questions.
TrueNAS 26: A (Tentative!) Release Timeline
The big headline this week is that Kris and Chris finally lay out the tentative roadmap from the first TrueNAS 26 BETA release all the way through to the .0 general availability. If you’ve been waiting to know when you can get your hands on the next generation of TrueNAS software, this episode gives you the clearest picture yet. No more codenames, no more decimal versioning — as the team confirmed back in Ep. 52, TrueNAS is moving to a clean annual release cycle, and 26 is the first major fruit of that shift.
Dataset Tiering: Hybrid Storage Gets Smarter
One of the standout features coming to TrueNAS 26 is dataset tiering — the ability to mix fast flash and spinning-disk pools and automatically tier datasets (or shares) between them. This is an Enterprise-tier feature, meaning it won’t land in the Community Edition, but the architecture is fascinating for anyone interested in how ZFS and TrueNAS manage data placement at scale. Since this is implemented at the TrueNAS layer rather than directly in OpenZFS, pools remain compatible with standard OpenZFS if you ever need to migrate away, though some caveats may apply.
For those of us running pure Community Edition homelabs — Docker stacks, S3-compatible storage, and all — it’s still a great signal of the direction TrueNAS engineering is heading.
Eight Viewer Questions
As always, Kris and Chris close out the episode with a batch of community questions — likely touching on storage configuration, upgrade paths, and follow-up on ZFS AnyRaid and Spotlight search (truesearch) from recent episodes.
Why This Episode Matters for Homelab Users
If you’re self-hosting on TrueNAS Scale — running Docker containers, managing snapshots over Tailscale, or experimenting with S3-compatible backends like RustFS or Garage — TrueNAS 26 is a significant milestone. The annual cadence promises more predictable upgrade windows, and features like dataset tiering give a window into where the platform’s storage smarts are heading.
Watch the full episode on the TrueNAS blog or on YouTube.
T3 Tech Talk is a weekly podcast from the TrueNAS team. New episodes drop every Thursday.
So …
/root 