issue 119: a hold is not a line in the apply report

2026-09-26 14:17:00 +02:00
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+---
+status: open
+opened: 2026-09-26
+located-in: [mesh-host internal/apply, mesh-controller]
+---
+
+# 119 — a hold is not a line in the apply report, and an operator flew blind into an outage
+
+## What was observed
+
+During the route-proxy edge cutover on novox (2026-09-26): the module was assigned, the
+push reported success, `status` said the node was doing everything it was told — and the
+module's three containers did not exist. The operator stopped the predecessor's proxy on
+the strength of those reports, and every public name on the node went dark until rollback.
+
+The cause was correct behaviour, invisibly reported. The first (rolled-back) route-proxy
+attempt had left `/var/lib/route-proxy/*` on disk; on re-assign, the adopted node *found*
+those directories, held them (ADR 0100, exactly as designed), and held every container
+that mounts them — `"would mount /var/lib/route-proxy/ca, found on this adopted node;
+not run until route-proxy is taken"`. All of that lived only in `state.json`. What the
+operator saw:
+
+- the push: `sent novox 346 resource(s)` — the controller's count of what it sent;
+- the node's journal: `applied 330 resource(s)` — sixteen fewer, with no line saying
+  which sixteen or why;
+- `status`: green — a held resource is not "wrong", so nothing was flagged;
+- `node show novox`: the holds list did NOT include route-proxy's (it showed only holds
+  the *controller* knew about from take-time listings, not what the node decided at
+  apply-time).
+
+Four surfaces, none carrying the one sentence that mattered: *route-proxy is assigned
+but not taken, and its containers will not run until it is.*
+
+## Why this is a real fault and not operator error alone
+
+The operator error (an edge-flip runbook that omitted `take`) was only possible because
+every surface reported success. A system whose correct refusals are indistinguishable
+from completed work will keep converting small procedural gaps into outages. The
+`sent 346 / applied 330` discrepancy was the single visible symptom, and interpreting it
+required reading `state.json` by hand.
+
+## What would have prevented it
+
+Any one of:
+
+1. **The apply report says what it held.** `applied 330 resource(s), 16 held for
+   untaken modules (route-proxy: 13, …)` — one line in the journal.
+2. **`status` counts holds against untaken-but-assigned modules.** A module assigned,
+   pushed, and running zero of its containers is at minimum worth a "waiting on take"
+   line — it is never converged in any useful sense.
+3. **`node show <node>` shows the node's own held list**, not only what take-time
+   computed — the node already records it in `state.json` with reasons.
+
+## Precedent
+
+The photos cutover hit the same semantics benignly the same week (assign → held
+containers in `Created` state → take), and the mailu cutover documented "take is the
+verb, and ADR 0100 meant it". The semantics are consistent and right; the reporting is
+what let them be forgotten at the worst moment.