# REPORT — R-203: the app and its backup look in the same place, and "ok" means it (2026-08-04)

**Controller v0.196.0 → v0.197.0**, deployed to demo-hp. No hub change. Nothing deleted, wiped or
moved on any box; the drill was **not** resumed. `demo-felhom` untouched.

---

## 1. Confirmed baselines, and §3's landmarks

`felhom-controller` `532f5712a891` (v0.196.0) → **v0.197.0**; `felhom.eu` `a0c4b607a6cf`, no bump.
Both trees clean on arrival. **Every §3 landmark held**, including the one that decided the fix:
`paths.go:26` names the system-drive arrangement *"the SSD-only system-data fallback"* — **it is
supported**, so the resolution was what was wrong and no API refusal was added.

## 2. The call sites found — **FIVE, not four**

| # | Site | Named by the spec? |
|---|---|---|
| 1 | `stacks/deploy.go` `withPathVars` → `${USERDATA_PATH}` | yes — the live defect |
| 2 | `appexport/fabplan.go` | yes |
| 3 | `appexport/export.go` | yes |
| 4 | `stacks/delete.go` `ExportDataMounts` | yes |
| 5 | **`web/handlers.go` FileBrowser mount builder** | **NO** |

The fifth is the customer's own file browser: on a non-enrolled path it would have mounted the wrong
directory. **Latent, not live** — the system drive is deliberately never a registered `StoragePath`, so
the resolver is the identity there today. Wired anyway, with that reason in the code.

Two further sites of the same class were found and fixed: `ComputeFabBuckets` was receiving the drive
path where `ComputeCaptureSet` has always received the namespace root, so the export's classified
paths and the backup's capture set could describe different directories for the same declared bind.

**The rule had TWO existing copies and they differed.** `backup.Manager.namespaceRoot` compared
without `filepath.Clean`; `stacks.Manager.inGuest` compared with it. A trailing slash from config
would have flipped the mode in one package and not the other. Both now delegate to
`appbackup.NamespaceRootFor`.

## 3. Scenario A — the two paths, before and after (live, demo-hp)

```
before:  /mnt/sys_drive/userdata/media/books            ← app bind; capture set looked elsewhere
after:   /mnt/sys_drive/felhom-data/userdata/media/books ← app bind == capture root
```

Capture log: **`0 mandatory path(s)`** → **`1 mandatory path(s)`**.

## 4. Scenario F — the sentinel in the snapshot's file listing

```
$ restic ls -l latest --tag calibre-web
-rw-r--r--  1000  1000  181  2026-08-04 12:53:06
  /mnt/sys_drive/felhom-data/userdata/media/books/DRILL-SENTINEL.txt
```

And the snapshot's own `paths`:
`["…/backups/primary/calibre-web", "/mnt/sys_drive/felhom-data/userdata/media/books"]`.

**Not a green status — the file, by name and size.** sha256
`643166269103a25cf41d34a26b75fd6ebba0a837bbcd7e0d2b5aba7106bcbe7c`, byte-identical to the drill's
step 3 after the fix's migration moved it into the corrected directory.

## 5. Scenario E — the delete path

**The §8.3 risk does not exist, and this is the correction owed.** `ExportDataMounts` lives in
`delete.go` but is **export-only**: its single production caller is the `.fab` export adapter and
nothing deletes on its result. The delete path's own guard, `ProtectedHDDPaths`, is **layout-agnostic
by construction** — it protects both `<hdd>/…` and `<hdd>/felhom-data/…` — so deletion was never
affected by the namespace-root defect. That note is now in the function's doc comment, because the
file placement misled this change's own specification.

**Does the corrected path point anywhere the old code did not?** Yes, for the export only, and only on
the system-data fallback: `<hdd>/felhom-data/userdata` instead of `<hdd>/userdata`. That is the
directory the app actually binds after this release, and the tests assert the **negative** — no
emitted path lies outside the app's own data roots, on either drive kind. It shipped as its own commit.

## 6. The verdict value

**`incomplete`** — **minted**, because `ok` | `error` | `running` contained nothing meaning *"it ran,
and this app is not fully protected"*. **Not `error`:** the rest of the run worked and what was
captured is real, so `SnapshotCount` and the `LastSuccess` anchor still record it.

It reaches the operator through the **existing** per-run digest, `backup_run_failures` — already
operator-only, already allowlisted. A new event type would have been a two-repo change and the hub
drops anything outside `allowedEventTypes`; the prompt ruled out a hub change. The Hungarian customer
warning is unchanged, and the backups page renders `! Hiányos` with the warn styling.

## 7. §8.4's narrowing — **no customer-visible warning disappears**

`TierOffsite`'s `tierKeeps()` already admits `ClassMandatory` only, so an optional path cannot reach
the stat-filter. The added class check is a **no-op today**, written for parity with Tier 2 — and
**demonstrated to be load-bearing anyway**: widening the tier filter alone keeps the tests green
*because of the check*; widening it and removing the check makes an optional gap start reporting.

## 8. §8.6's live effect — anticipated, and then NOT reproducible

Anticipated in the CHANGELOG before it could fire: calibre-web on demo-hp had exactly this gap, so its
status would become `incomplete`. **In the event it did not**, because the same session fixed the
underlying path — after the corrected bind and the data migration the app has no gap, and the run is
legitimately `ok`.

**Attempting to observe the verdict live by hiding the directory did not work, and that is recorded
rather than dressed up:** the running container's bind mount **recreated** it, so `os.Stat` succeeded
and no gap existed. Worth knowing in itself — a bind-mounted directory cannot easily be "missing"
while its app runs, so the mandatory-gap condition arises in practice when the path resolves somewhere
the app never binds (the R-203 case), not when a live app's own directory vanishes. The verdict is
proven by a run-level test that drives the real `RunOffboxBackup`. The fixture was restored and the
sentinel re-verified at the same hash.

## 9. Tests and every red-proof

| Scenario | Result | Red-proof — mutation → outcome |
|---|---|---|
| A both paths agree | PASS + **LIVE** | restore the bare-path call → **FAIL**: `/mnt/sys_drive/userdata` vs `/mnt/sys_drive/felhom-data/userdata` |
| B enrolled drive unchanged | PASS | invert the drive-kind comparison → **FAIL** on every enrolled row |
| C mandatory gap → not ok | PASS | unreachable gap recording → **FAIL**; unconditional `ok` → **FAIL** |
| D optional gap → ok | PASS | class check removed **with the tier filter widened** → **FAIL**; tier widened alone → PASS, i.e. the check holds the line |
| E export mounts, both kinds + the negative | PASS | leave the site bare → **FAIL**, emits the short path |
| F sentinel in the listing | **LIVE** | — |

**A RED-PROOF PASSED AND THE TEST WAS WRONG, NOT THE CODE** (§9.11 — three of the last six sessions).
My first Scenario-C test exercised `offboxCaptureSet` alone, while the mutation lives in
`runOffboxInternal`. A mutation the test cannot observe is not a red-proof. Replaced with a run-level
test that drives `RunOffboxBackup` and asserts `incomplete`, the retained `LastSuccess`, and the
operator signal; it fails under both mutations. The original Scenario-D "red-proof" also could not
fail by construction — recorded above with the two-part mutation that does.

Green gate after each phase (`go build && go vet && go test ./...`, rc=0) plus
`controller_gates.py --fast`. No test run was combined with a commit.

## 10. Commits

| Commit | Contents |
|---|---|
| `73efb09` | Part 1 — one resolver, the four non-export sites, `ComputeFabBuckets`, the two delegating copies |
| `a96c3d9` | **Part 1.3 alone** — the `delete.go`-resident export-mount site, with its scope correction |
| `58c703b` | Part 2 — the verdict, the structural gaps, the operator digest, the status rendering |
| `73fb595` | docs (felhom.eu) |

## 11. Registers

- **R-203 → SHIPPED + PROVEN-LIVE.**
- **R-201 → READY TO RESUME**, blocker gone, fixture staged and verified.
- **R-202 stays open**; the orphaned-ciphertext deletion is **still owed**.
- Capability map: new row for mandatory-path capture on both layouts, its predecessor corrected as
  optimistic, and the **R-199 back-pointer omitted two sessions ago is now added**.
- The v0.93.0 `identity_blob` retention remains **unit-proven only** — nothing here superseded a key.

## 12. CI

Run numbers and task ids in the session summary. **`--no-verify` was not used.**

## 13. Teardown

**Nothing provisioned.** `calibre-web` and the sentinel stay — R-201 needs them. The temporarily
hidden directory was restored and the sentinel re-verified byte-identical.

## 14. Observations — noticed, NOT acted on

1. **`resolveAbs` uses ONE root for two bind classes.** `RootHDD` resolves against the same parameter
   as `RootUserdata`. On an enrolled drive they coincide; on the system-data fallback a `${HDD_PATH}`
   bind resolves under the namespace root while compose binds it bare. Both callers now pass the
   namespace root, so the export and the backup **agree with each other** — but whether `${HDD_PATH}`
   itself should mean the namespace root on the system drive is a separate question that touches every
   already-deployed app's binds. **Not fixed here; it needs a decision, not a patch.**
2. **The blast radius was measured before changing anything:** exactly one app in the fleet has
   `HDD_PATH == system_data_path` — `calibre-web` on demo-hp, deployed for the drill. Every other
   deployed app has no `HDD_PATH`. Nothing else needed migrating.
3. **`/api/stacks/<name>/deploy` is first-deployment-only** (409 afterwards), so the corrected
   `${USERDATA_PATH}` reaches an existing app through a start/redeploy, not a re-deploy.
4. **The controller's CSRF form field is `_csrf`, not `csrf_token`** — the login page uses one name and
   the protected forms another. Second session in a row this cost time; it belongs in the
   headless-access memory.
