docs(ep0): hub PBS-DR capacity gauge verified correct after the volume move

The last open item from the datastore relocation. Hub operator UI
(Offsite -> PBS DR) reports felhom-offsite (ep0) at 97.9 GB capacity,
12.6 GB used, 13% full - agreeing with the on-box df (98 G / 13 G / 13%).

The gauge follows the datastore's CONFIGURED PATH, so the relocation
required no hub-side change. RUNBOOK section 10.3 warned that a stale
37.2 GB reading would mean the gauge reads the wrong filesystem and
would be a real bug worth a roadmap item - it does not, and there is
no bug.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018ARoadHBf8rHoscfiqeVZn

REPORT-ep0-datastore-volume-2026-07-27.md

@@ -14,8 +14,8 @@ Written as `REPORT-<topic>.md` per the parallel-session rule — the shared `REP
 | | Before | After |
 |---|---|---|
 | Path | `/srv/pbs-felhom` (root disk) | **`/mnt/pbs-datastore`** (volume) |
-| Datastore total | 37.2 GB | **98 GB** |
-| Used | 28.9 % | **13 %** |
+| Datastore total | 37.2 GB | **98 GB** (hub gauge: 97.9 GB) |
+| Used | 28.9 % | **13 %** (hub gauge: 12.6 GB, 13 %) |
 | Headroom to the 80 % warn | 19 GB | **≈65 GB** |
 | Additional customers before warn | ≈2 | **≈7–13** |
 
@@ -84,7 +84,9 @@ layout that R-39/R-82 made self-healing are untouched.
    volume, with explicit go-ahead.
 2. **GC not run** — now unblocked by the round-trip, but left for a separate deliberate run. No GC
    schedule is configured on this PBS at all.
-3. **Hub PBS-DR capacity gauge not re-read** — the hub is a ClusterIP service and was not reachable
-   from DooPlex. If it still reports 37.2 GB it is reading the wrong filesystem: a real bug.
+3. ~~Hub PBS-DR capacity gauge not re-read.~~ **CLOSED — verified correct.** The hub operator UI
+   (Offsite → PBS DR) reports `felhom-offsite (ep0)` at **97.9 GB capacity, 12.6 GB used, 13 % full**,
+   agreeing with the on-box `df`. The gauge follows the datastore's configured path, so the move
+   needed no hub-side change and the suspected "wrong filesystem" bug does not exist.
 4. **ep0 has no swap** (temporary 4 GB file removed; box left as found). Worth a small permanent
    swapfile — outside this runbook's scope.

documentation/architecture/07-backup-architecture.md

@@ -365,8 +365,10 @@ backups/secondary/<stack>/
 > **Re-measure rather than trust this table** once a second weekly snapshot exists — the weekly
 > incremental size is still **UNMEASURED**, and it, not the total, decides the real slope.
 >
-> ⚠️ The hub's PBS-DR gauge had **not** been re-read at the time of writing; if it still reports
-> 37.2 GB it is reading the wrong filesystem, which is a real bug worth a roadmap item.
+> ✅ **The hub's PBS-DR gauge tracked the move correctly** (verified 2026-07-27, Offsite → PBS DR):
+> `felhom-offsite (ep0)` — **capacity 97.9 GB, used 12.6 GB, 13 % full**. It follows the datastore's
+> configured path, so the relocation needed no hub-side change. The feared "gauge reads the wrong
+> filesystem" bug **does not exist**.
 
 Recorded per the operator's 2026-07-26 ruling: **the datastore will be grown later; R-82 proceeds
 meanwhile.** These are measurements, not projections-of-record — re-measure before relying on them.

documentation/runbooks/RUNBOOK-ep0-datastore-volume-2026-07-27.md

@@ -427,8 +427,13 @@ rm -f /root/.ssh/storagebox_ed25519 /root/.ssh/storagebox_ed25519.pub   # access
 4. **ep0 has no swap** (removed the temporary 4 GB file; the box is as found). A 3.7 GB box with
    zero swap is what turned a routine 13 GB copy into an OOM kill. Worth considering a small
    permanent swapfile — not done here, as it is outside this runbook's scope.
-5. **Hub PBS-DR capacity gauge** (§10.3) not yet re-read — it should now report ~98 GB, not 37.2 GB.
-   Could not be queried from DooPlex: the hub is a ClusterIP service and was not reachable directly.
+5. ~~**Hub PBS-DR capacity gauge** (§10.3) not yet re-read.~~ **CLOSED — verified correct
+   2026-07-27** via the hub operator UI (Offsite → PBS DR):
+   `felhom-offsite (ep0)` — **capacity 97.9 GB, used 12.6 GB, 13 % full**, polled 12 min prior.
+   The gauge follows the datastore's *configured path*, so the relocation required no hub-side
+   change. **§10.3's "if it still shows the old size that is a real bug" does not apply — there is
+   no bug.** (It could not be queried from DooPlex directly — the hub is a ClusterIP service — so
+   this was read from the operator UI.)
 6. **`x-systemd.device-timeout=30s` means a genuinely missing volume delays boot by 30 s** before
    `nofail` lets boot continue. Accepted trade-off.