030 — asking what a machine should be re-signed its certificate

Composing a declaration signed the machine's certificate anew each time, and a signing carries a fresh random serial — so what the mesh would send differed from what it had sent by one byte, for ever, and every machine carrying a certificate stood eternally waiting. Third find of the same rule: issued once and kept. The port had it, the secret had it, the certificate composed fresh on every asking — and the keeping column had existed since the serving-key migration, written by nothing, the same shape ReleasePorts was found in. Found by keeping the scenario standing and diffing two plans seconds apart: one line, where four theories had none.
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+---
+status: fixed
+opened: 2026-09-01
+located-in: [mesh-control]
+fixed-by: mesh-control 38d4e77
+amended-design:
+---
+
+# 030 — Asking what a machine should be re-signed its certificate
+
+## Symptom
+
+Every machine carrying a certificate reported as *waiting* — not running what the mesh would send
+it — for ever. Pushed seconds ago, already behind again. Nothing wrong, nothing failed, nothing
+quiet; only a comparison that never came out equal.
+
+It surfaced as the one red test in four consecutive runs, and wore three other faults' clothes
+first: a test racing the apply it asserted on, a status command that wrote to the database it was
+reading, a machine starved at its default size. Each was real; each was fixed; the symptom stayed.
+
+## Cause
+
+The mesh signs a certificate for a machine's internal name as part of composing its declaration —
+and signed **anew on every composition**. Same authority, same key, same name, same validity
+window; a fresh random serial each time, because that is what signing does. So the declaration
+composed to answer *is this machine current* differed from the declaration sent by exactly one
+serial number, every time, deterministically.
+
+The comparison is a digest, so one changed byte is as unequal as a different world.
+
+## How it was found, which is the lesson
+
+Not by deduction — deduction produced the three wrong theories above. The suite was run once with
+its scenario kept standing, and the standing mesh was asked twice: `plan`, `plan`, diff. Two
+answers seconds apart, identical to the byte but for one serial, in the certificate file. The
+diff had one line where four theories had none.
+
+A verdict machine that can be kept and interrogated is worth more than the verdict.
+
+## The rule it broke, third find of its kind
+
+**Issued once and kept.** The port had it, the secret had it, the certificate did not — composed
+fresh on every asking, by the same code that holds the other two still. And like
+[`028`](../028-two-things-want-one-port-and-nothing-says-so/00-report.md)'s ReleasePorts, the
+keeping was designed and never wired: the serving-key migration added a column *"and what was
+issued for it"*, and nothing wrote it.
+
+A kept certificate stands while the name, the key and the clock agree. A node that rejoined with
+a new key or changed its name gets a fresh signing exactly as if nothing were kept; so does one
+whose certificate is into its last tenth of life.
+
+## Verified
+
+Live, on the kept mesh, before any suite run: one push with the fixed binary and the machine
+settled; the second machine likewise; then the mesh's own sentence — all doing what they were
+told, running what the mesh would send them.