fcbfb5618147db1a014a548f84dfd1b887b85cc2
3 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 Joseph Doherty
|
e7fbe97759 |
fix(historian): gate historization capture on the Primary, quarantine a poison tag (#537, #538)
Both defects were found by #491's live gate against a real HistorianGateway and filed rather than fixed at the time, because each one's fix is a design decision rather than a patch. #537 — both nodes of a redundant pair captured every value, so the historian received duplicate live samples for every historized tag (measured: the gateway's write counter advanced twice per value and halved when one central was stopped). The recorder now reads a capture gate per value, fed from the new PrimaryGatePolicy.ShouldRecordHistorizedValues through IHistorizationRoleView — a third verdict on the same RedundancyRoleView object, registered unconditionally on driver nodes rather than alongside the alarm section's IRedundancyRoleView (which only exists when that section is enabled; piggybacking is the #511 registration accident). Two things are deliberate and easy to get backwards: * It gates the CAPTURE, not the drain — the opposite of the alarm sink. That queue is in LocalDb and replicates, so the Secondary already holds the Primary's rows. The historization outbox is a node-local FasterLog replicating to nobody, so a drain-only gate would leave the standby appending forever to a queue no one empties: unbounded disk, then a flood of stale duplicates the moment it is promoted. Entries a node already captured are still drained by that node. * The peer it stands down for must RECORD THE SAME REFS, not merely hold the same rows — a Primary in this node's own per-cluster mesh. A node carrying no cluster-scoped role cannot establish that and never stands down: under a fleet-wide election the elected Primary is usually running a different cluster's configuration, and deferring to it would end this cluster's historization silently, with the drain reporting success on an empty outbox forever. That is the scope mismatch that once suspended the alarm drain on every node of the rig. An unknown role captures, matching the alarm drain — a duplicate sample is recoverable, a hole in the trend is not. #538 — the drain writes every per-tag group and then acks all-or-nothing (deliberate: RemoveAsync truncates THROUGH an id, so partial acking could drop older unwritten entries). One permanently failing tag therefore pinned the FIFO head while every healthy tag in the batch was re-submitted to the historian on every pass, indefinitely — duplicate samples and an outbox that never truncated, observed live at 8.3 MB from a single unprovisionable tag. The drain now tracks consecutive failures per historian tag and abandons that tag's entries once it exceeds MaxWriteAttempts (new, default 5), so the head advances. The counter only advances on a pass where some OTHER tag wrote successfully: that is what separates "this tag is poison" from "the backend is down". A count-only quarantine looks identical on the poison-tag case and silently discards the whole backlog during an ordinary gateway restart, turning a duplicate-samples bug into a lost-history one. Abandonment is also deferred until every failing tag is over budget, so nothing is discarded on a pass that could not have advanced the head anyway. Each abandonment logs a Warning naming the tag; the total rides RecorderStatus.AbandonedEntries. Capacity also gains a non-zero default (500,000 entries) as the disk backstop for the one case the quarantine deliberately cannot resolve — a historian refusing every write, where retaining is correct. Set 0 to restore unbounded retention. Every new test was falsified by reverting the production change it guards, and each one reddens alone: * drop the backend-reachable evidence -> only A_backend_that_fails_every_tag_abandons_nothing * never abandon -> only A_permanently_failing_tag_is_abandoned_so_healthy_tags_stop_being_rewritten * latch the capture gate at construction -> only The_capture_gate_is_re_read_per_value... * treat any Primary as a scope peer -> only the two scope-mismatch cases Full suite green. (Four OpcUaClient.Browser failures during the run were the opc-plc fixture being down on the shared Docker host; brought it back up and they pass.) Claude-Session: https://claude.ai/code/session_015p7wGqy3YpZNCpDzTpGMKo |
||
|
Joseph Doherty
|
f9f1b8fcee |
fix(localdb): phase-2 live gate — 4 production defects found and fixed
Gate record: docs/plans/2026-07-20-localdb-phase2-live-gate.md. Checks 1, 2, 5, 6 pass. Checks 3 and 4 are NOT satisfied — the defect they were meant to confirm turned out to be the opposite of what the plan assumed. Three defects crash-looped every driver node before check 1 could even run: 1. An empty ServerHistorian:ApiKey kills the host. ServerHistorianOptions- Validator exists to turn exactly that class of failure into a named OptionsValidationException, but its documented fail tier explicitly excluded ApiKey on the reasoning that a keyless client "degrades — the gateway rejects calls". It does not: the client validates its own options at construction, so the process dies during Akka startup and never makes a call. 2. UseTls disagreeing with the endpoint scheme kills the host too, in both directions (both messages confirmed in the shipped client assembly). Moving an endpoint from https to http without clearing UseTls is an ordinary migration slip. 3. Plaintext h2c was UNREACHABLE. HistorianGatewayClientAdapter forwarded the TLS-only options unconditionally, and AllowUntrustedServerCertificate defaults to false, so it always sent RequireCertificateValidation=true — which the client rejects outright when UseTls=false. Every http:// deployment crashed, though the scheme is documented as the supported way to select h2c, and the only workaround was to assert a certificate posture for a connection that has no certificate. The fourth was the blocker, and it is Phase 2's own: 4. The drain gate deferred to a Primary that cannot deliver. Redundancy roles are elected CLUSTER-WIDE; the alarm queue is PAIR-LOCAL. On the rig the elected driver Primary is central-1 — it carries the driver Akka role, replicates nobody's LocalDb and does not even run the alarm historian — so every driver node logged "Historian drain suspended", including the two site-b nodes that have no peer at all. Nothing drained anywhere, where before Phase 2 it drained fine. The cost is not a duplicate; it is the buffer growing to the capacity wall and evicting the audit trail it exists to protect. Fixed in three layers: a separate ShouldDrainAlarmHistory policy (unknown role drains; the two gates now deliberately disagree, and a test pins that); peer- host matching in DriverHostActor so a node stands down only for a Primary holding its rows; and AddAlarmHistorian short-circuiting the gate when replication is unconfigured — testing BOTH Replication:PeerAddress and SyncListenPort, since only the dialing half sets the former while both halves share the queue. Every one of these follows from the asymmetry: a false allow costs a duplicate row, which at-least-once delivery already accepts and payload-hash ids collapse; a false deny loses data silently. A third vacuous test, caught by the same delete-the-guard discipline: the role-view tests stayed green with the guard removed, because AwaitAssert polls until an assertion passes and the assertion was "reads open" — which is the SEEDED value, satisfied at the first poll before the actor processed anything. They now assert the sequence of published values through a recording view; the control then goes red for exactly the cases that matter. Migration evidence: 11 legacy rows across two deliberately overlapping files converged to exactly 9 identical rows on both nodes, proving D-6's payload-hash identity on real nodes rather than in a fixture. Open design fork, recorded in the gate doc rather than decided here: a pair cannot currently identify its own Primary, so both halves drain. Safe in every topology — nothing loses data — but the gate's de-duplication benefit is unrealised until roles are scoped per pair. Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW |
||
|
Joseph Doherty
|
f2e899aaad | feat(r2-04): PrimaryGatePolicy - membership-aware default-deny + denial meter (03/S4) |