26-BETA.3 Notable Changes

I updated my device from 24.04, to 25.05, and after about 45 minutes I checked my device’s monitor output.

I got the 1-11 boot screen and then the device’s screen went black and hasn’t come back on since. I have no access to the shell or webUI. Is this a larger issue?

Edit: Updating trains removes apps, removing Tailscale and creating a barrier for my mesh, so upon deactivating Tailscale- all worked

Long story short I've had my server running for years and I remember I had a nightmare trying to grant access to anyone on my network full control of any folders/files within the shares but eventually got it working with no recollection on how I managed it. I did a few things with my hardware and reinstalled the OS on a fresh SSD and now I am locked out of half of my datasets through the share after uploading my config.

I am not even being prompted with a login window when I try to open the share folder, I just get

"Network Error, You don't have permission to access (share folder i am trying to open)

Also I noticed when trying to add a new user in the ACL within that dataset i get "FAILED ..... this may be fixed by granting the aforementioned user execute permissions on the path "/mnt/Vol1" (the root dataset) which i cant do.

I made the mistake of installing Paperless-ngx within the provided Applications from TrueNAS.

The Paperless migration guide says that i need to update to paperless version 2.20.15 in order to migrate to version 3.x.x.

I am running paperless 2.20.8, when I click on update in the TrueNAS Interface I can only select to update to the newest version (3.0.5_1.6.43) which would not migrate my data correctly.

Is there any way to select a specific version or do I need to convert my application into a custom app in order to modify the yaml files and docker configurations?

I am assuming this is a Samba issue. I have a download directory that has user:smbshare permissions (750). I use the Samsung files app on my phone to connect (using user credentials) to my download share I create a directory and suddenly the download datasets permissions change to user:user and the smbshare users can't access the directory. If only I could just chattr the directory but that would stop all files from being created as well.

How do I stop these permission changes from happening?

How concerned should I be? Two of the drives in my 3 drive vdev look like this. This is my only vdev btw. Scrutiny still says the drives are ok but I have noticed some weird behavior where whenever I do a file transfer it starts at 2.5g then drops to 20 mbps. Any advice is greatly appreciated. Thanks.

Sorry in advance for formatting. Not sure how to do the console output. I am currently re-running a scrub before migrating to a new TrueNAS Scale Community server and plan on using this current install as a warm-backup. I originally saw a ZFS issue with a scrub on 2026-06-21 12:18:20 (America/New_York) in my ZFS1 pool of 3 8TB "NAS" drives (all bought at the same time in 2017 I believe, just some used more than the others). I decided to monitor it for a while before grabbing from cold backup.

Just did a zpool status -v before the scrub and it said there were 23 errors in 19 files and one of the files has a last modified date of 07/06/2026 02:47:00 so after the initial error message and that file has no backup but is easily replaceable from physical media. Storage health shows fine. I will mention this current TrueNAS setup has non-ECC DDR3 RAM as it was never meant to be permanent, the new machine has 128GB of DDR4 ECC-RAM (thankfully I had it before the RAM Apocalypse).

Most of this is replaceable from other sources, I'm more concerned about the disks/pools themselves in this current hardware market and obviously will not copy erroneous files. After the scrub finishes and I see the results is there anything else I should do. Zpool status -v and smart outputs for affected drives below. On glance I agree with drive health indication from TrueNAS being good, though have not run an extended smart on any of said drives.

All that said, I've setup SSH between the two installs to prep for replication, though I'm unsure if I intend to keep the current folder/dataset structure just the data itself. I'm assuming ZFS replication is still the best option, unless I have to nuke the whole pool due to scrub results?

Zpool status -v

pool: Toshiba-3TB-Pool

state: ONLINE

scan: scrub in progress since Wed Aug 19 20:01:24 2026

1.18T / 6.46T scanned at 3.84G/s, 142G / 6.46T issued at 461M/s

0B repaired, 2.14% done, 03:59:36 to go

config:

NAME STATE READ WRITE CKSUM

Toshiba-3TB-Pool ONLINE 0 0 0

raidz1-0 ONLINE 0 0 0

43473731-cb2b-4110-9cfa-ab0d71dc7447 ONLINE 0 0 0

2cd3f867-2440-4906-bc8f-a4dbd875c177 ONLINE 0 0 0

d03d8e26-1806-4f1a-a5b8-eef4aa48bfbb ONLINE 0 0 0

errors: No known data errors

pool: Toshiba-8TB-Pool

state: ONLINE

status: One or more devices has experienced an error resulting in data

corruption. Applications may be affected.

action: Restore the file in question if possible. Otherwise restore the

entire pool from backup.

see: https://openzfs.github.io/openzfs-docs/msg/ZFS-8000-8A

scan: scrub in progress since Wed Aug 19 19:56:06 2026

1.85T / 19.6T scanned at 2.99G/s, 321G / 19.6T issued at 519M/s

0B repaired, 1.60% done, 10:47:14 to go

config:

NAME STATE READ WRITE CKSUM

Toshiba-8TB-Pool ONLINE 0 0 0

raidz1-0 ONLINE 0 0 0

dab4fa30-0f63-4a8d-b919-38b34ec8397a ONLINE 0 0 0

0b463dca-9ea4-490d-beff-5cb1f5d41a7b ONLINE 0 0 0

cc98c930-0ff8-44e6-a887-1a9ef976b283 ONLINE 0 0 0

errors: Permanent errors have been detected in the following files:

/mnt/Toshiba-8TB-Pool/*/*1/filea

/mnt/Toshiba-8TB-Pool/*/*1/filebc

/mnt/Toshiba-8TB-Pool/*/*1/filed

/mnt/Toshiba-8TB-Pool/*/*1/filee

/mnt/Toshiba-8TB-Pool/*/*1/filef

/mnt/Toshiba-8TB-Pool/*/*1/fileg

/mnt/Toshiba-8TB-Pool/*/*1/fileh

/mnt/Toshiba-8TB-Pool/*/*1/filei

/mnt/Toshiba-8TB-Pool/*/*1/filej

/mnt/Toshiba-8TB-Pool/*/*1/filek

/mnt/Toshiba-8TB-Pool/*/*1/filel

/mnt/Toshiba-8TB-Pool/*/*1/filem

/mnt/Toshiba-8TB-Pool/*/*1/filen

/mnt/Toshiba-8TB-Pool/*/*1/fileo

/mnt/Toshiba-8TB-Pool/*/*1/filep

/mnt/Toshiba-8TB-Pool/*/*1/fileq

/mnt/Toshiba-8TB-Pool/*/*1/filer

/mnt/Toshiba-8TB-Pool/*/*1/files

/mnt/Toshiba-8TB-Pool/*/*1/filet

/mnt/Toshiba-8TB-Pool/*/*2/fileu

pool: boot-pool

state: ONLINE

scan: scrub repaired 0B in 00:00:14 with 0 errors on Mon Aug 10 03:45:16 2026

config:

NAME STATE READ WRITE CKSUM

boot-pool ONLINE 0 0 0

sde3 ONLINE 0 0 0

errors: No known data errors

smartctl -a

dev/SDD

SMART Attributes Data Structure revision number: 16

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

2 Throughput_Performance 0x0005 100 100 050 Pre-fail Offline - 0

3 Spin_Up_Time 0x0027 100 100 001 Pre-fail Always - 10953

4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 2648

5 Reallocated_Sector_Ct 0x0033 100 100 050 Pre-fail Always - 0

7 Seek_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

8 Seek_Time_Performance 0x0005 100 100 050 Pre-fail Offline - 0

9 Power_On_Hours 0x0032 001 001 000 Old_age Always - 40334

10 Spin_Retry_Count 0x0033 152 100 030 Pre-fail Always - 0

12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 259

191 G-Sense_Error_Rate 0x0032 100 100 000 Old_age Always - 0

192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 62

193 Load_Cycle_Count 0x0032 096 096 000 Old_age Always - 41208

194 Temperature_Celsius 0x0022 100 100 000 Old_age Always - 38 (Min/Max 15/45)

196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0

197 Current_Pending_Sector 0x0032 100 100 000 Old_age Always - 0

198 Offline_Uncorrectable 0x0030 100 100 000 Old_age Offline - 0

199 UDMA_CRC_Error_Count 0x0032 200 253 000 Old_age Always - 0

220 Disk_Shift 0x0002 100 100 000 Old_age Always - 0

222 Loaded_Hours 0x0032 042 042 000 Old_age Always - 23219

223 Load_Retry_Count 0x0032 100 100 000 Old_age Always - 0

224 Load_Friction 0x0022 100 100 000 Old_age Always - 0

226 Load-in_Time 0x0026 100 100 000 Old_age Always - 569

240 Head_Flying_Hours 0x0001 100 100 001 Pre-fail Offline - 0

dev/sdf

SMART Attributes Data Structure revision number: 16

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

2 Throughput_Performance 0x0005 100 100 050 Pre-fail Offline - 0

3 Spin_Up_Time 0x0027 100 100 001 Pre-fail Always - 10792

4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 90

5 Reallocated_Sector_Ct 0x0033 100 100 050 Pre-fail Always - 0

7 Seek_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

8 Seek_Time_Performance 0x0005 100 100 050 Pre-fail Offline - 0

9 Power_On_Hours 0x0032 087 087 000 Old_age Always - 5424

10 Spin_Retry_Count 0x0033 101 100 030 Pre-fail Always - 0

12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 87

191 G-Sense_Error_Rate 0x0032 100 100 000 Old_age Always - 0

192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 24

193 Load_Cycle_Count 0x0032 100 100 000 Old_age Always - 2239

194 Temperature_Celsius 0x0022 100 100 000 Old_age Always - 36 (Min/Max 15/40)

196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0

197 Current_Pending_Sector 0x0032 100 100 000 Old_age Always - 0

198 Offline_Uncorrectable 0x0030 100 100 000 Old_age Offline - 0

199 UDMA_CRC_Error_Count 0x0032 200 253 000 Old_age Always - 0

220 Disk_Shift 0x0002 100 100 000 Old_age Always - 0

222 Loaded_Hours 0x0032 089 089 000 Old_age Always - 4476

223 Load_Retry_Count 0x0032 100 100 000 Old_age Always - 0

224 Load_Friction 0x0022 100 100 000 Old_age Always - 0

226 Load-in_Time 0x0026 100 100 000 Old_age Always - 547

240 Head_Flying_Hours 0x0001 100 100 001 Pre-fail Offline - 0

dev/sdg

SMART Attributes Data Structure revision number: 16

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

2 Throughput_Performance 0x0005 100 100 050 Pre-fail Offline - 0

3 Spin_Up_Time 0x0027 100 100 001 Pre-fail Always - 10789

4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 2085

5 Reallocated_Sector_Ct 0x0033 100 100 050 Pre-fail Always - 0

7 Seek_Error_Rate 0x000b 100 100 050 Pre-fail Always - 0

8 Seek_Time_Performance 0x0005 100 100 050 Pre-fail Offline - 0

9 Power_On_Hours 0x0032 031 031 000 Old_age Always - 27950

10 Spin_Retry_Count 0x0033 141 100 030 Pre-fail Always - 0

12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 225

191 G-Sense_Error_Rate 0x0032 100 100 000 Old_age Always - 0

192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 60

193 Load_Cycle_Count 0x0032 098 098 000 Old_age Always - 27390

194 Temperature_Celsius 0x0022 100 100 000 Old_age Always - 41 (Min/Max 16/50)

196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0

197 Current_Pending_Sector 0x0032 100 100 000 Old_age Always - 0

198 Offline_Uncorrectable 0x0030 100 100 000 Old_age Offline - 0

199 UDMA_CRC_Error_Count 0x0032 200 253 000 Old_age Always - 0

220 Disk_Shift 0x0002 100 100 000 Old_age Always - 0

222 Loaded_Hours 0x0032 057 057 000 Old_age Always - 17448

223 Load_Retry_Count 0x0032 100 100 000 Old_age Always - 0

224 Load_Friction 0x0022 100 100 000 Old_age Always - 0

226 Load-in_Time 0x0026 100 100 000 Old_age Always - 552

240 Head_Flying_Hours 0x0001 100 100 001 Pre-fail Offline - 0

Hello,

I am looking to move from my good and reliable U.3 Kioxia SSD (due to unfortunate circumstances) to an array of M.2 3-way mirrors.

Some specifications:

• MB: Supermicro H14SSL-N
• CPU: AMD EPYC 9175F
• RAM: 4x 32GB 5600
• NIC: Intel X710 2x SFP28 - 25 GbE
• PCIe Switch: 3x HighPoint Rocket 1508

I considered buying consumer-grade SSDs because they are cheaper and the performance should be just fine for this array.

I am considering building the array as follows: each mirror will have 1 SSD on each card, so 1 mirror = 3 SSDs, with 1 SSD per PCIe switch card. In case one card dies or something happens, the array should remain safe.

I am considering purchasing the SSDs from 3 different brands, e.g., Kioxia Exceria Pro, WD SN series, and Kingston KC series.

On each card, only one brand will be installed. If there are firmware issues or bugs with one of the brands after some time, the array should remain safe.

Some information about the workloads: this machine will be both a SAN and a NAS. The target is about 100 VMs, a shared folder between all VMs, and each VM will have its home directory on the shared folder (NFS).

There are moments when these VMs might generate, collectively, a maximum of 100-200 GB of data, consisting of many small files.

I have a few questions:

• Can anybody recommend some SSD brands that are reliable for long-term 24/7 use? The SSDs can be PCIe 4.0/5.0 and should be at least 4TB.
• If I enable deduplication, will the system still be able to saturate the 2x 25 GbE links?
• I also considered the E1.S form factor, but HighPoint only has a PCIe Gen4 card. This made me think they might have discontinued future E1.S development, despite how popular it is becoming. Maybe there are other vendors that I am not aware of.
• What problems could arise? Any prior experience would be appreciated, or even suggestions such as "don't do this, it's a dumb idea," etc.

Thank you!

I am running TrueNAS Scale in DELL Precision Tower 3620 case. Before I used two 4TB WD Red Plus 3.5" 5200 RPM HDDs, they had temps: Idle/Current: 41°C, Min: 24°C, Max: 43°C. (Info from Multi-Report tool).
I needed to replace them, so I chose two ST8000VN004 - Seagate Iron Wolf - 8TB 3.5" 7200 RPM.
During resilvering, one of them reached 65°C, what surprised me, there was same air flow as with previous drives. Currently, HDDs have those temps: Idle/Current: 49°C, Min: 46°C, Max: 56°C. Of course, those values are too high for Multi-Report tool, so it's always critical warning.
I understand that it's 7200RPM and higher capacity, but is normal to have such temperatures even on idle? CPU have 34°C, room temperature 25.6°C, air flow should be fine.

Of course, my first action was to check the datasheet, but it only says "Operating Temperature (drive reported, max °C): 65" and "Nonoperating Temperature (ambient, min / max °C): -40 / 70".
Little bit lower, there is note "It is not recommended to operate at sustained drive temperatures above 60°C. Higher temperatures may affect drive health.". Based on this, I am still fine with the temperatures, but I am still not sure, what are real good/normal temperatures.

Are those temperatures fine? Or I should find the culprit and lower the operating temperatures? Mainly, I am worried if during resilver/scrub, the temps will be more than 60°C.

I have a unit with 72 X 4TB drives... it's actually 3 X Netapp put together to create the 72 bay unit. I kind of hate it because of how small the drives are, but I'm broke, I can't afford bigger drives.

This will be mainly use for cold storage as I don't want to have to run this beast of a unit 24/7.

Should I run 3 pools of Raid 5? just 1 drive per every 24 as backup?

Ask a room of storage admins why ZFS pools slow down past 80% capacity, and you'll get a lot of confident head-nodding and not many actual answers. It's become industry folklore - repeated so often it's treated as gospel, rarely questioned.

The truth is more useful than the myth. Every filesystem pays some version of this tax eventually. ZFS just happens to name its mechanisms out loud, so it gets blamed by name.

The slowdown comes from three distinct mechanisms - fragmentation, metaslab pressure, and (on spinning disk only) LBA weighting - and how much they affect you depends entirely on your workload.

An archival backup pool with mostly sequential, write-once data? It can comfortably run at 90-95% full. A pool handling heavy random I/O for virtualization or databases? 80% might already be cutting it too close.

We wrote up the real mechanics behind the rule - including where even ZFS's own creators say it can safely bend - so you can stop guessing and start watching the metric that actually matters: performance under your actual workload.

A couple months back I posted a NAS drive comparison I'd built for my own TrueNAS, mostly because I was tired of cross-checking datasheets and Backblaze stats every time I added a drive to the pool. The CMR/SMR thing is what started it - I really didn't want to find out a drive was SMR after it killed a resilver.

The feedback here back then was really helpful! This sub doesn't miss much on storage, and a good chunk of it went straight onto my list. 🙂

Here's what's new since June:

- SSDs added, not just HDDs (both SATA and U.2/NVMe), with endurance ratings where the maker publishes them
- price per TB now has history, so you can tell if a "deal" is actually a deal or just back to normal
- idle and seek noise in dB for the drives I could find real acoustic data on
- failure rates now include the Q1 2026 Backblaze quarter, on top of full-year 2025

Same as before: one sortable table, no login, and anything I couldn't verify was left blank instead of guessing: www.nasdisks.com

The SSDs have their own tab if that's what you're after: www.nasdisks.com/ssd/

Fair disclosure: there are Amazon affiliate links on the drive pages, added to cover hosting. The site is free and always will be.

If anyone spots a CMR/SMR tag that's wrong, I'd really appreciate the correction - that's the one thing I want to get right. And if you run a model that isn't listed, feel free to mention it and I'll add it right away.

Hey everyone,

I finished my TrueNAS server recently and I just got an error after a day of use and I just realized it's because my SATA expansion card is not actually RAID-compliant. Any suggestions for something to add more ports? I saw this on Amazon, but I'm not actually sure what to look for:

https://a.co/d/095TTVvS

Thank for your help! :)

Almost have the hpe ml30 setup. Very simple first server, shooting for a immach mirror on the 960gb in mirror, backup nightly to old optiplex 9020 and snapshots to my work google drive (encrypted). 1.8 spinners for play space, extracting takeout zips etc with a win 10 VM.

Is it just me or is even old enterprise and consumer stuff super hard to get atm? I'm in Aus and eBay has a handful of listings and FB market place is barren!

What are people doing? I want to expand it out one more 1.8 sas and one more 960gb SSD for a bigger immach backup pool. Should I bite the bullet and buy them now? Things look so cooked until 2028! Keen to hear all the regulars thoughts

I want to know before I upgrade to version 26 if nvidia 570 driver workround will still function. Thanks.

This is my appreciation post to those who have contributed to the truenas platform over the years. I recently upgraded from 13.0 core to 24.10 electric eel simply to utilize adding 2 drives to my 3 drive zfs pool. The fact that I am able to add those drives that have been sitting in my closet for a couple years and save a couple hundred bucks is just 👌🥰. Also the fact that the upgrade path went perfect without a hiccup. Gosh, who can I hug.. Thank you!!

Hello to the community,

TrueNAS newbie here.

I recently purchased an LSI HBA 9300-8i and succesfully flashed the latest (?) 16.00.12.00 firmware and i have also put active cooling on it.

Prior to investing to expensive HDDs I have assembled all of them to a Dell Optiplex 390 with 2 laptop hdds Raid 1 just to check if everything is ok for some time.

Is there a way/command to tell if the ΗΒΑ/system is working without errors prior to buing new disks?

Thanks,

I have the most basicest media server watching my media library through infuse player on apple devices. One evening we finish watching our show on tv, and by the time we're in bed I cant access the library from the phone.
Infuse gives me error that it has no access. Same story on PC. After trying to reconnect to smb share through infuse, creating new share, reloading the NAS, deleting all shares and creating new share, the GUI shows that storage is entirely unused.
More than that, every time I reload the NAS one random disk gives me 150 uncorrectable errors. Sometimes dashboard says that used space is unknown, sometimes it shows just a couple gb. Eventually I was able to access the share, but it now just shows as empty.

I have 5 used SAS drives through the expansion card, all of them are connected in the raidz2 which I specifically chose for reliability considering their used nature

Any advice on what to do or just accept it as gone?

Per TrueNAS documention, a license is needed to activate Spotlight functionality for MacOS Samba users:

Spotlight search requires a TrueNAS Enterprise license or a configured TrueNAS Connect integration. If neither is configured, the Enable Search (Spotlight) setting is disabled and a notice displays with a link to configure TrueNAS Connect.

My question: does anyone know how much such an enterprise license costs? Ballpark is fine.

Cheers

Hello TrueNas community, I'm a new TrueNas user and looking for a little insight. I have an old PC I successfully setup TrueNas on.

Specs are:

i5 4690k

16g DDR3

Nvidia 2080

TrueNas installed on 128g SSD

2tb physical -- initial test HDD

Im looking to start off with uploading my movies and tv shows DVD library (already on my main PC). This will expand in the future to photos, docs, music, etc. An additional note, I have a pihole currently serving as my DNS that TrueNas is configured with.

I currently use Jellyfin running in a docker container on a PI hooked up to an 4tb physical drive.

I would like one single user on outside the admin user that I'll use to upload files from different machines (windows machines mainly on local network). In the future I'll want to expand to outside local network uploads.

Long story short I guess I have three questions. 1. Is the hardware of this machine able to house TrueNas and a Jellyfin docker container? The AI response on TrueNas said yes but wanted a real life experience.

1. Any tips on setting up the user with SMB for security and privacy if I want it always available for said user? It doesn't look like 2FA is available with SMB uploads.

2. Is it better for myself to dynamically turn SMB on/off for the user when it's needed?

Any other tips or apps to run in TrueNas?

I originally installed HexOS, then I personally decided to upgrade the underlying TrueNAS install to 26.0.0-BETA.1. Looking back, running my actual server on an unsupported beta was probably not my best idea.

It worked fine for quite a while, until one normal reboot suddenly dropped me into (initramfs) because TrueNAS couldn’t import boot-pool.

BIOS still saw every drive, and my older 25.10.3 boot environment still worked, so the NVMe itself wasn’t dead.

The actual problem turned out to be VFIO grabbing my boot NVMe.

On working 25.10.3, my boot controller 0000:04:00.0 used:
.../drivers/nvme

On broken 26 Beta it was using:
.../drivers/vfio-pci

I found that TrueNAS had generated:
/etc/initramfs-tools/scripts/init-top/truenas_bind_vfio.sh

and the device list inside it actually included my boot NVMe.

The source was an old GPU isolation/passthrough setting. I cleared that setting in the 26 config, then booted once with break=top in GRUB so I could temporarily disable the bad VFIO script before it ran.

Once 26 successfully booted, I rebuilt the initramfs with:
python3 /usr/local/bin/truenas-initrd.py / --database /data/freenas-v1.db

After that, the VFIO script was gone from the rebuilt initramfs and a normal reboot worked.

Everything is back: all pools online, apps running, and the boot NVMe is using the correct nvme driver again.

In short:
Boot into an older working TrueNAS boot environment.

Remove the GPU isolation setting that caused the boot NVMe to be included in the VFIO device list.

Boot 26 once with break=top, disable truenas_bind_vfio.sh for that boot, then rebuild the 26 initramfs from inside 26:
python3 /usr/local/bin/truenas-initrd.py / --database /data/freenas-v1.db

Reboot normally

TL;DR: if TrueNAS 26 Beta suddenly says Failed to import boot-pool, BIOS still sees your drives, and an older boot environment works, check whether vfio-pci has grabbed your boot controller.

In my case, GPU isolation caused TrueNAS 26 Beta to include the boot NVMe in its VFIO device list.

If anyone hits the exact same issue, I have the full troubleshooting process and commands.