TrueNAS 25.x mounts /usr as a read-only filesystem. Writing
sitecustomize.py to site-packages and patching the Angular bundle
both fail with EROFS.
Fix: mount a writable overlayfs on each target directory before
writing to it. Upper/work dirs live in /run (tmpfs), so overlays are
volatile per boot and are recreated by apply.sh on every PREINIT run
before middlewared starts.
apply.sh:
- Add _ensure_writable(dir, tag): probes writability; mounts overlay
in /run/truecloud-{tag}-{upper,work} if the directory is read-only;
detects if the overlay is already mounted (idempotent)
- Call _ensure_writable before site-packages writes (tag "sc")
- Detect webui dir with bash loop; call _ensure_writable before
patch_ui.py (tag "ui") — non-fatal if mount fails
uninstall.sh:
- Add overlay unmounting section after file restoration and before
rm -rf, so the lower layer's originals are exposed immediately
- Move _restore_failed exit 1 to after unmount so overlays are
cleaned up even on partial failure
- Update "no backup files" message for immutable OS context
truenas-truecloud-patch
Extends TrueNAS SCALE's TrueCloud Backup feature to work with S3-compatible providers and native Backblaze B2, instead of Storj only.
Why this exists
In 2026, Storj raised the price of their TrueNAS-integrated storage tier from $5/month to $50/month — a 10× increase. For many home lab and small-office users, the TrueCloud Backup feature became unaffordable overnight.
TrueCloud Backup is the only native TrueNAS mechanism that provides:
- Integrated ZFS snapshot support before each backup
- Restic-based incremental deduplication
- Scheduled tasks with progress and log tracking in the UI
- Dataset lock integration
Running restic manually is possible but loses all of the above. This patch restores access to the TrueCloud Backup feature for users who need a provider other than Storj, with storage they already pay for or that costs a fraction of the new Storj price.
⚠ Disclaimer — please read before installing
This project is unofficial, unsupported, and not affiliated with iXsystems or the TrueNAS project in any way.
By installing this patch you accept the following:
-
Unsupported configuration. TrueNAS support staff are not obligated to help with any issue on a system running this patch. If you file a bug report, remove the patch first and reproduce the issue on an unmodified system.
-
May break on TrueNAS updates. The patch targets internal middleware APIs that are not part of any public contract. They can change at any time. When they do, the patch silently degrades to Storj-only behaviour rather than breaking TrueNAS — but you should check the log after each update.
-
Your backups are your responsibility. Verify that your backup jobs complete successfully and that restores work before relying on them for disaster recovery.
-
No warranty. This software is provided as-is. See the LICENSE file.
If TrueNAS ever adds native support for additional providers in TrueCloud Backup, uninstall this patch immediately.
What is actually patched
Nothing in TrueNAS's persistent database or configuration is modified.
The patch operates on two files that live in /usr/ (which TrueNAS replaces
on every update) and are therefore re-applied automatically on every boot.
| Layer | What changes | Technique |
|---|---|---|
| Backend | B2RcloneRemote gains get_restic_config(). restic.py URL builder is fixed for providers with no hostname component (b2:bucket/path vs the broken b2:/bucket/path). |
sitecustomize.py — Python's standard startup hook; no middleware files are modified on disk |
| UI | The Angular bundle's filterByProviders binding is widened from ["STORJ_IX"] to ["STORJ_IX","S3","B2"] |
In-place text replacement in the compiled JS bundle; original is backed up |
Both changes are fail-safe: if a patch cannot be applied (e.g. TrueNAS
restructured the relevant code), middlewared starts normally with Storj-only
support and the reason is logged to apply.log in your repo root.
Supported providers after patching
| Provider | Credential type in TrueNAS |
|---|---|
| Backblaze B2 (native B2 API) | B2 |
| AWS S3, Wasabi, Cloudflare R2, MinIO, and any S3-compatible endpoint | S3 |
| Storj (unchanged) | STORJ_IX |
How persistence works
TrueNAS SCALE updates replace /usr/ entirely. The patch survives by keeping
this repository on a persistent ZFS pool (your data pool, not /tmp or a
system path) and registering a PREINIT initshutdownscript in the TrueNAS
database. On every boot, patch/apply.sh runs from the repo before
middlewared starts, placing sitecustomize.py in the correct site-packages
directory and re-patching the UI bundle.
Python version compatibility
sitecustomize.py uses the find_spec / exec_module import hook API
(introduced in Python 3.4, required from Python 3.12 onwards). This covers:
- TrueNAS SCALE 24.x — Debian 12, Python 3.11 ✓
- TrueNAS SCALE 25.x — Debian 13, Python 3.12 ✓
Install
Clone the repository to a persistent ZFS pool so it survives OS updates,
then run install.sh from there:
# Replace /mnt/tank with your pool name
git clone https://github.com/sudolulo/truenas-truecloud-patch.git \
/mnt/tank/truenas-truecloud-patch
cd /mnt/tank/truenas-truecloud-patch
bash install.sh
The directory you clone into becomes the permanent install location. The PREINIT boot hook points to it — do not delete or move the repo after install.
Refresh your browser. S3 and B2 credentials now appear in the Data Protection → TrueCloud Backup → Add credential dropdown.
Creating a credential
Before creating a backup task, add a credential in the TrueNAS UI:
Data Protection → TrueCloud Backup → Add → (create new credential)
Or use Credentials → Backup Credentials → Cloud Credentials → Add and select B2 or Amazon S3.
For S3-compatible providers, select Amazon S3, then set a custom endpoint
in the credential's advanced settings (e.g. https://s3.wasabisys.com).
Creating a task via CLI
If the UI still shows only Storj after refreshing (e.g. the JS bundle pattern changed in a new TrueNAS version), create tasks directly via the REST API:
# Replace /mnt/tank/truenas-truecloud-patch with your clone path
# List your cloud credentials to find the right ID
python3 /mnt/tank/truenas-truecloud-patch/patch/create_task.py \
--host 192.168.1.1 --api-key <key> list-credentials
# Create a task with a B2 credential (id=3)
python3 /mnt/tank/truenas-truecloud-patch/patch/create_task.py \
--host 192.168.1.1 --api-key <key> create \
--name "tank-to-b2" \
--path /mnt/tank/data \
--credential 3 \
--bucket my-bucket \
--folder backups/tank \
--password "restic-repo-password" \
--keep-last 14
Get an API key from System → API Keys → Add.
Uninstall
bash /mnt/tank/truenas-truecloud-patch/uninstall.sh
Replace the path with your clone location. Removes the PREINIT hook,
sitecustomize.py, and restores the original UI bundle from backup. The
backend changes vanish on the next middlewared restart.
Restoring from a TrueCloud Backup
TrueCloud Backup uses restic under the hood. Restores
are done with the restic command directly — TrueNAS does not yet expose a
restore UI for TrueCloud Backup tasks.
1. Find the restic binary
which restic 2>/dev/null || find /usr -name restic -type f 2>/dev/null | head -1
Use that path in the commands below (referred to as restic).
2. Gather your repository details
You need three things from the task you created:
| Detail | Where to find it |
|---|---|
| Bucket and folder | TrueNAS UI → Data Protection → TrueCloud Backup → edit the task → Attributes |
| Credentials (key ID + secret) | TrueNAS UI → Credentials → Backup Credentials → edit the credential |
| Repository password | The --password value you supplied when creating the task |
3. Set environment variables
Backblaze B2:
export B2_ACCOUNT_ID="your-key-id"
export B2_ACCOUNT_KEY="your-application-key"
export RESTIC_PASSWORD="your-repo-password"
REPO="b2:your-bucket/your-folder"
S3-compatible (AWS S3, Wasabi, Cloudflare R2, MinIO, etc.):
export AWS_ACCESS_KEY_ID="your-access-key"
export AWS_SECRET_ACCESS_KEY="your-secret-key"
export RESTIC_PASSWORD="your-repo-password"
# Use just the hostname as the endpoint — no https:// prefix:
REPO="s3:s3.wasabisys.com/your-bucket/your-folder" # Wasabi example
# REPO="s3:s3.amazonaws.com/your-bucket/your-folder" # AWS S3
# REPO="s3:<account>.r2.cloudflarestorage.com/your-bucket/your-folder" # R2
4. List snapshots
restic -r "$REPO" snapshots
Output example:
ID Time Host Tags Paths
──────────────────────────────────────────────────────────
a1b2c3d4 2026-06-01 02:00:05 truenas /mnt/tank/data
e5f6a7b8 2026-06-08 02:00:07 truenas /mnt/tank/data
5. Restore files
Restore everything from the latest snapshot to a temporary location:
restic -r "$REPO" restore latest --target /mnt/tank/restore-tmp
Restore a specific snapshot by ID:
restic -r "$REPO" restore a1b2c3d4 --target /mnt/tank/restore-tmp
Restore only specific paths from within a snapshot:
restic -r "$REPO" restore latest \
--include /mnt/tank/data/important-dir \
--target /mnt/tank/restore-tmp
Browse a snapshot without extracting (useful for finding the right file):
restic -r "$REPO" ls latest
6. Notes
- Restore to a different path first, then move files into place after verifying. Restoring directly over a live dataset can cause data loss if the snapshot is incomplete or from the wrong point in time.
- If you created the task with
--snapshot(ZFS snapshot before each run), the restic snapshot captures the dataset at a consistent point in time. - Use
restic check -r "$REPO"periodically to verify repository integrity.
After a TrueNAS update
- Check the log:
cat /mnt/tank/truenas-truecloud-patch/apply.log | tail -30 - If you see "WARNING: … pattern not found", the UI patch needs updating. Open an issue with your TrueNAS version number.
- The backend patch (B2 support + URL fix) is more stable — check that a B2 backup job still completes successfully after any update.
Emergency recovery
middlewared won't start
Run this from the TrueNAS shell (local console, SSH, or the debug shell in the UI):
bash /mnt/tank/truenas-truecloud-patch/recover.sh
Replace the path with your clone location. This creates a kill-switch file
(disabled) in the repo root. sitecustomize.py checks for it at Python
startup; if present, the import hook is skipped entirely and middlewared starts
clean with Storj-only support. Nothing else on your system is affected.
If you cannot run a script and only have a bare shell prompt:
touch /mnt/tank/truenas-truecloud-patch/disabled
systemctl restart middlewared
If you don't remember where you cloned the repo (midclt won't work while middlewared is down), find the path two ways:
# Option 1 — search the filesystem:
find /mnt -name "recover.sh" -path "*/truenas-truecloud-patch/*" 2>/dev/null
# Option 2 — query the TrueNAS database directly:
sqlite3 /data/freenas-v1.db \
"SELECT script FROM initshutdownscript WHERE comment = 'TrueCloud provider patch (S3/B2)';"
The script column shows the full path to patch/apply.sh; your clone root is one
level up (strip /patch/apply.sh from the end). Then run the touch command above
with that path.
If middlewared still won't start after the kill switch is set, the problem is unrelated to this patch. Check:
journalctl -u middlewared -n 50
To re-enable the patch once you have investigated:
rm /mnt/tank/truenas-truecloud-patch/disabled
bash /mnt/tank/truenas-truecloud-patch/patch/apply.sh
Web UI is blank or broken
If the TrueNAS web interface loads blank or shows JavaScript errors, the Angular bundle may have been interrupted mid-write (e.g. power cut during boot). The original bundle is always backed up before patching, so recovery is straightforward:
# Find the backup (the path varies by TrueNAS version):
find /usr/share/truenas /var/www/truenas -name "*.js.pre-truecloud-patch" 2>/dev/null
# Restore it — substitute the actual path from the find output:
mv /usr/share/truenas/webui/main.XXXXXXXX.js.pre-truecloud-patch \
/usr/share/truenas/webui/main.XXXXXXXX.js
Refresh your browser. The UI will return to normal (Storj-only until the
patch re-runs at next reboot, or you run
bash /mnt/tank/truenas-truecloud-patch/patch/apply.sh manually).
Backend verify shows FAIL
python3 /mnt/tank/truenas-truecloud-patch/patch/create_task.py verify
If one or more entries show [FAIL]:
- Check the apply log for errors during the last boot:
cat /mnt/tank/truenas-truecloud-patch/apply.log | tail -40 - Check middlewared's own log for Python tracebacks:
journalctl -u middlewared -n 50 - A FAIL is non-fatal. middlewared runs normally; the affected provider falls back to Storj-only. Your existing backups are not at risk.
- If the detail says the module doesn't exist, a TrueNAS update renamed or restructured the internal API. Open an issue with your TrueNAS version number and the full verify output.
Troubleshooting
Apply log (check after each reboot or install):
cat /mnt/tank/truenas-truecloud-patch/apply.log
Verify backend patch is loaded (while middlewared is running):
python3 /mnt/tank/truenas-truecloud-patch/patch/create_task.py verify
This reads hook_status.json in your repo root, written by the import
hook once both target modules have been loaded by middlewared. If it reports
"No hook status file found" immediately after install, restart middlewared
and try again — the file is written when middlewared imports the relevant
modules, which happens at service start.
Does not require --host or --api-key.
Verify the UI patch (should print your TrueNAS version):
grep -c 'STORJ_IX.*S3.*B2' \
$(find /usr/share/truenas -name '*.js' 2>/dev/null) 2>/dev/null \
| grep -v ':0'
B2 backup fails with credential error
Confirm the credential type is exactly B2 (not S3 with a B2 endpoint).
B2's native restic backend uses a different auth path than S3-compatible B2.
S3-compatible backup fails S3 support already existed in the backend — the credential setup is the likely issue. Verify the endpoint URL, access key, secret key, and bucket name in the credential settings.
create_task.py SSL error connecting to TrueNAS
create_task.py talks to the TrueNAS API, not your S3 endpoint, and
verifies its TLS certificate. If your NAS uses a self-signed certificate,
pass --insecure — but be aware this disables certificate verification for
the API call that transmits your TrueNAS API key. Adding your NAS certificate
to your system's trust store is safer.