Marc-André Bombeck
2c295bbea8
The boot key check recorded whatever key was configured whenever its probe found nothing to try. It only read string columns, so an install whose ciphertext sat in Bytes columns (notes, documents, ECG, symptoms) read as empty; a probe that ran out of time did the same; and rows written by a process that served under a wrong key could open on the next boot and get that key recorded as the right one. The probe now reads every registered column, string and Bytes, in all four stored layouts, and tries the oldest values first, ordered by the row's updatedAt (else createdAt, else primary key). A key is recorded only when the oldest value that opens is preceded by at most one that does not, or when no column holds a single value under the key id. A time-out, an unreadable table, oversized values or mixed results are inconclusive: the process serves, records nothing and checks again at the next start. When the first insert loses a race, the stored record is read back and must open under this process's key, else the outcome is a mismatch. A rotation that walked every column without errors removes the record of each previous key id that no longer holds any value. The refusal log block and the self-hosting pages explain how to reset the check for a key id.
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HealthLog on TrueNAS SCALE
HealthLog runs on TrueNAS SCALE as a Docker app: one app container from
ghcr.io/mbombeck/healthlog and one PostgreSQL 16 database. The app container
is stateless; everything you care about lives in the database dataset and in
one value you must keep yourself: the encryption key.
What the app needs
| Setting | Value |
|---|---|
| Image | ghcr.io/mbombeck/healthlog, tag X.Y.Z (amd64 and arm64) |
| Port | 3000 (HTTP) |
| User | runs as uid 1001; no extra capabilities, no-new-privileges is fine |
| Health check | GET /api/health, 200 when ready |
| Start period | at least 60 s, with more retries than the image's 3 × 30 s: migrations run at every boot |
| Database | PostgreSQL 16 (17 and later are not a drop-in), no extensions |
| Volumes | none for the app; the database gets its own dataset |
Environment
| Variable | Required | Notes |
|---|---|---|
DATABASE_URL |
yes | postgresql://<user>:<password>@<host>:5432/<db> |
ENCRYPTION_KEY |
yes | 64 hex characters: openssl rand -hex 32. Keep a copy outside the NAS (see below). |
API_TOKEN_HMAC_KEY |
yes | 64 hex characters, generated the same way. Changing it signs everyone out. |
NEXT_PUBLIC_APP_URL |
yes | the address people open, for example http://truenas.local:30180 |
APP_URL |
yes | the same address |
SESSION_COOKIE_SECURE |
no | false for a LAN install served over plain http://; leave unset behind an HTTPS proxy |
HEALTHLOG_PLATFORM |
no | truenas: the admin's key backup step opens on the TrueNAS instructions |
GEOLITE2_DIR |
no | a mounted directory of GeoLite2 .mmdb files, so sign-in locations are resolved on the NAS |
HEALTHLOG_PROCESS_TYPE stays unset (all): one container serves the web app
and runs the background jobs.
Plain HTTP on the LAN
Most NAS installs are reached over http://. Set SESSION_COOKIE_SECURE=false
for that. If it is left at its default, the browser drops the sign-in cookie
and the login page says so before you type a password: "This server only sets
its sign-in cookie over https://".
Back up your encryption key
HealthLog encrypts tokens, notes, documents and in-database backups with
ENCRYPTION_KEY. The key is not stored in the database. If the app is deleted
and reinstalled with a new key over the old database dataset, the data is
still there but cannot be read.
-
Copy
ENCRYPTION_KEYfrom the app's settings (Apps, HealthLog, Edit, Environment) into your password manager. -
Sign in as the admin and open Admin, Encryption. The step shows the key id and a fingerprint, the first 12 hex characters of SHA-256 over the key. Compare it with your copy:
echo -n "<your key>" | xxd -r -p | sha256sum | cut -c1-12or paste the copy into "Check my copy" (it is compared and dropped, never stored or logged).
-
Confirm the backup. Until you do, admins see a reminder on the dashboard. After a key rotation the step comes back for the new key.
When the key does not match the database
At every start HealthLog checks that its key opens the data already in the
database. If it does not, it refuses to serve instead of failing on every
encrypted value: pages show "HealthLog cannot open its data", API requests
answer 503 with meta.errorCode encryption.key_mismatch, /api/health
answers 503 with reason: "encryption_key_mismatch", and no background jobs
run. TrueNAS shows the app as unhealthy rather than crashed, so the reason
stays visible.
Fix it one of three ways, then restart the app:
- Put the original
ENCRYPTION_KEYback. - Point
DATABASE_URLat the database that belongs to this key. - Start fresh with an empty database. The old data and its backups need the old key.
Before it records a key as the right one, the check reads the oldest
encrypted values in the database and records the key only if they open (or if
the database holds no encrypted value under that key id yet). When the data
proves neither, the app keeps serving, records nothing, writes a warning
starting with [boot] Encryption key check inconclusive to the log, and
checks again at the next start.
Resetting the check
If you are certain the configured key is the one the data was written with,
and the app still refuses because the check recorded a different key earlier,
remove that record and restart. Open a shell on the database container (Apps,
HealthLog, the database container's Shell) and run, with the key id the log
names (v1 unless you use ENCRYPTION_KEYS):
psql -U healthlog healthlog \
-c "DELETE FROM encryption_key_canaries WHERE key_id = 'v1';"
Then restart the app. It probes the stored data again and records the key only if that data opens with it. If the key is in fact wrong, the app then fails on every encrypted value instead of refusing clearly, so only do this when you are sure. After a key rotation you never need this for the old key id: the rotation script removes its record once no values remain under it.
Updates
Pick the new tag, take a snapshot of the database dataset first, and update. Migrations run on start; the first start of a new install applies all of them, which is why the start period above is generous.