TrueNAS CORE · TrueNAS SCALE · FreeNAS · iXsystems Mini · ZFS
TrueNAS / FreeNAS NAS data recovery. ZFS remembers everything, if you don't force the import.
TrueNAS and its predecessor FreeNAS run ZFS, which checksums everything, writes nothing in place, and keeps a history of pool states on every disk. A pool that will not import at its latest state usually imports read-only at an earlier one from images, with every dataset intact. The losses come from the shell: a forced import with -F or -X that discards the history, a scrub or a resilver run against a second weak disk, a clear that hides the fault. Every disk is imaged, including the SLOG, and the pool is imported read-only from the images at the latest consistent transaction. Any pool of two or more disks is £500 + VAT upwards; eight disks and above from £1,250 + VAT, in writing after the free look.
Rather talk it through? An engineer answers the bench line
0800 6890668
Models we see, family by family.
Which kind of unit is it →| Family | Models | Bays, OS, file system and layout |
|---|---|---|
| Home-built | Any PC with TrueNAS or FreeNAS | Any vdev layout · ZFS |
| iXsystems | TrueNAS Mini X, Mini R, R-series | 4–24 bays · ZFS |
| FreeNAS era | FreeNAS 9 to 11 on old hardware | ZFS, sometimes with GELI |
What tends to go wrong on a TrueNAS / FreeNAS.
TrueNAS / FreeNAS symptoms, and how long each gives you.
Not listed? Describe it on the form →What the message means on a TrueNAS / FreeNAS.
Describe yours to us →| What you see | The usual reason | Where that leaves you |
|---|---|---|
| Pool DEGRADED, still imports | Redundancy lost | Copy out; power down; no scrub |
| cannot import: devices unavailable / corrupted data | Members missing or metadata damaged | Read-only import from images at an earlier transaction |
| Pool FAULTED / UNAVAIL | Too many members lost | Each member imaged; pool assembled from images |
| -F already run | History discarded to the rewind point | Imported from images; assessed honestly |
From the box arriving to your files going back.
Work we have closed →Logged the day it lands, and the first look costs nothing Free
A case number goes on the parcel and a number on every drive the day it is opened, and an engineer settles what has actually happened before anything spins. The unit is examined on its own; each drive is assessed on our own equipment, never in a NAS that will try to rebuild. Back to you come two things together: a straight note of what is liftable and what is not, plus one figure, fixed and written down. Accept it, or decline and owe us nothing.
The unit, and the drives, apart
The box and the disks are two different jobs. The unit is tested separately, because a dead power supply, a failed board or a bricked boot flash leaves the drives untouched more often than not. Each drive is then read on the bench: the ones that answer at full speed, and the weak or failed ones in clean air where they need head work. On units that hold an encryption key or a layout of their own, the unit is part of the data and is kept with it.
Every member imaged, once
Nothing is worked on live and nothing is rebuilt on the originals. Every drive in the set is imaged sector by sector, the weak ones head by head with the bad areas last, and the SSD cache with them where there is one. From then on the originals are not touched again.
The set put back together, from the images
Order, chunk size, parity rotation and the reshape point are read from the drives' own metadata and the array is reassembled in software: mdadm and LVM under SHR, X-RAID and QTS pools; a ZFS pool imported read-only; Drobo's BeyondRAID zones reconstructed. The file system, Btrfs, ext4, XFS or ZFS, is repaired on the virtual volume, and encrypted volumes are unlocked there with the key you supply. Never on the originals.
You see the file list before you pay
What was recovered is listed for you first, and only then does a bill exist. Approve the list and it is invoiced; turn it down and it is not — and where nothing has come back, most jobs carry no charge at all. Recovered data travels home on fresh media bought in for your job, with the postage at our end. Your case is not closed until you have opened the files on a machine of your own.
From the bench
- ZFS keeps its history on every disk. A pool that will not import at its latest state usually imports read-only at an earlier one from images. -F and -X discard that history on the originals.
- Send the SLOG and the boot device with the data disks. The log device holds synchronous writes not yet on the pool.
- Tell us every command that was run. A forced import, a clear or a labelclear changes the plan.
What helps, and what harms.
Do this much first
- Power down and copy out the exact error
- Note every disk's slot and serial
- Send every disk, the SLOG and the boot device
- Send the commands that were typed
What sets us back
- zpool import -F or -X
- zpool clear, a scrub or a labelclear
- Replacing a disk to trigger a resilver
- Reinstalling to see whether it imports
Questions answered before you commit.
My pool will not import. Is the data gone?
Rarely. A read-only import from images at an earlier transaction group usually brings the datasets back whole. Do not force it on the originals.
Can a PC read the drives from my TrueNAS / FreeNAS?
No. They carry a Linux volume, usually over mdadm, and a PC offers to initialise them. They are mounted from images on the bench.
What does it cost?
Any set is £500 + VAT upwards; four bays and above from £1,250 + VAT, fixed in writing after the free look.
How long does it take?
5–10 days at the bench for a set; 3–4 days at the bench for a single drive.
Begin here if yours is doing the same thing.
Nothing gets worse while it is powered down.
Looking at it is free. Back comes a list of what opened and what did not, together with a single price to finish, set down in writing while you are still free to say no. On most jobs an invoice only follows the data. Until that list reaches you, leave the unit off and the drives in their bays.