The AdminUI "Test Connect" probe for the Sql driver: open a connection, run
the dialect's LivenessSql (SELECT 1) under a linked-CTS deadline, return
green with latency or red with a reason. Implements IDriverProbe; never
throws (malformed JSON, missing connectionStringRef, unprovisioned
connection string, a provider open failure, timeout, cancellation all
become red results).
Parses the SAME factory DTO with the SAME JsonStringEnumConverter as
SqlDriverFactoryExtensions (R2-11 factory parity, mirroring
ModbusDriverProbe) and resolves connectionStringRef the same way, so a
config that Test-Connects is the config that Deploys.
Credential hygiene: the resolved connection string never reaches the result
message. A provider exception can embed the data source in its OWN message
(the real SqlException shape), so the catch-all names the exception TYPE
only, never ex.Message. The regression test's fake connection embeds the
connection string in its thrown message specifically so surfacing ex.Message
would leak it — verified load-bearing by breaking the guard and watching it
go red.
ForTest injects factory+dialect for the offline SQLite fixture path.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
SqlDriverFactoryExtensions turns a deployed DriverConfig blob into a live
SqlDriver, and SqlConnectionStringResolver resolves the authored
connectionStringRef NAME from Sql__ConnectionStrings__<ref> so credentials
never ride in a config blob (design §8.2).
Three behaviours worth naming:
- String-enum guard. JsonOptions carries JsonStringEnumConverter +
camelCase, so `provider` parses whether authored as a name or an ordinal
and always round-trips as the NAME — the systemic AdminUI defect where a
page serialised an enum numerically against a string-typed DTO.
- Config validation lands here because nothing below does it.
operationTimeout must be STRICTLY greater than commandTimeout (design
§8.3); the reader and the driver stay deliberately usable with the pair
inverted so the frozen-database tests can prove the client-side bound
fires. Non-positive timeouts / poll interval and maxConcurrentGroups < 1
are rejected too.
- Credential hygiene. The resolved connection string reaches the provider
and nothing else: messages name the ref, the environment variable, or
SqlDriver.Endpoint's credential-free server/database rendering. Both a
log-leak and an exception-leak test cover it.
DTO changes:
- Adds RawTags (List<RawTagEntry>), following the Modbus precedent — the
deploy artifact delivers a driver's tags this way and the DTO had no way
to receive them, so an authored Sql tag could never reach the driver.
- Deletes SqlProbeDto + the `probe` key. It had no consumer: SqlDriver was
specified without a background probe loop, and deliberately so — its
IHostConnectivityProbe state is a by-product of the Initialize liveness
check and of every poll, i.e. a statement about traffic that actually
happened rather than a synthetic ping. On-demand connectivity is Task
10's SqlDriverProbe. Shipping a config key that silently does nothing is
worse than not shipping it; UnmappedMemberHandling.Skip means a blob that
still carries `probe` keeps parsing.
allowWrites stays inert (SqlDriver implements no write capability) but an
authored `true` now WARNS rather than passing silently — the flag cannot do
harm, an operator who believes writes are enabled can.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Opens one transient DbConnection from a form-supplied driver-config blob and
hands ownership to SqlBrowseSession, which closes it on disposal. A database is
named either by connectionStringRef — resolved in the AdminUI process from
Sql__ConnectionStrings__<ref>, with an unresolvable ref naming the exact missing
variable — or by a pasted, session-only literal. The literal wins and the ref is
then not read; it cannot arrive from a persisted blob (SqlDriverConfigDto has no
such property), so its presence proves an operator typed it now.
Credential hygiene is the point of the type: no cached config field, nothing
persisted, and no connection text in any log line or exception. Live-probed:
Microsoft.Data.SqlClient and Microsoft.Data.Sqlite keep connection-string values
out of SqlException/SqliteException, but their connection-string PARSER echoes an
unrecognised keyword verbatim — and an unquoted ';' inside a password splits, so
the tail of the password is reported as a keyword (Password=Sup3r;SecretTail =>
"Keyword not supported: 'secrettail;connect timeout'."). The parser's message is
therefore never surfaced; every other failure additionally passes through a
substring redactor that drops the inner exception when it fires.
DriverType comes from SqlDriver.DriverTypeName, the driver's interim local
constant — DriverTypeNames.Sql is added by the driver-factory task.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Three review findings against SqlPollReader (967e5140).
1. WideRow's where-pair form emits no ORDER BY and no row limit, so a
selector that is not actually unique made the reader publish an
arbitrary, storage-order-dependent row — silently, unlike IndexByKey's
duplicate-key warning. Row selection moves out of MapMember into a new
SelectWideRow, which is called once per group and emits the same
rate-limited contract warning (naming table, selector and row count).
The row-limit half of the suggested fix was deliberately NOT taken: a
TOP 1 with no ORDER BY is not deterministic either, and it would
destroy the Rows.Count > 1 evidence the warning depends on, turning a
loud misconfiguration into a permanently silent one. Rationale is in
SelectWideRow's docs. No SQL changed, so no planner golden string moved.
2. The "a frozen database can never accumulate more than
maxConcurrentGroups connections" claim was asserted in the docs and
untested. ReadAsync_aTimedOutGroupKeepsItsConcurrencySlotUntilTheQuery-
TrulyFinishes wedges a group behind an EXCLUSIVE transaction, times it
out, and proves the slot is still held (a second poll on a cap of 1
times out on the gate without ever reaching the factory) and is handed
back only once the abandoned query truly finishes. Moving the release
from the work to the waiter fails this test and no other.
3. Task.Run thread-pool starvation: documented, not changed.
Microsoft.Data.SqlClient's async path parks no pool thread on a frozen
server, so the driver cannot starve itself; LongRunning would cost a
dedicated OS thread per group per poll forever to insure against a
provider this driver does not ship. RunGroupAsync now records the
decision and what a BadTimeout does and does not mean, for the
blackhole gate.
Also: the timeout warning now names the group's table, so a BadTimeout
storm identifies which source is frozen.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Walks schemas -> tables/views -> columns via ISqlDialect's catalog SQL, with
@schema/@table bound as parameters at every level. Column leaves carry the
dialect-mapped DriverDataType in the attribute side-panel (ViewOnly, read-only
v1).
The NodeId encoding deliberately departs from the design sketch's literal
`schema.table|column`: SQL Server permits `.` and `|` inside a quoted
identifier, so that form mis-parses (main.a.b|c reads equally as schema
`main`+table `a.b` and schema `main.a`+table `b`) and silently binds an
operator's tag to the wrong column. SqlBrowseNodeId encodes
`<kind>:<part>[|<part>...]` with `\`/`|` escaped and the kind prefix carrying
the arity; it is public because the picker body decodes it back.
The session owns the connection it is handed and closes it on dispose -- the
registry-held session is the only lifetime hook, so a non-owning session would
leak one pooled connection per reaped picker. Per-call work stays bounded by
the AdminUI's existing 20s linked CTS (BrowserSessionService.PerCallTimeout);
no second deadline is invented here.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
SqlDriver implements IDriver / ITagDiscovery / IReadable / ISubscribable /
IHostConnectivityProbe / IAsyncDisposable over the landed SqlPollReader,
mirroring ModbusDriver. IWritable is deliberately absent: v1 is read-only
structurally, and every discovered variable is SecurityClass=ViewOnly.
The shell classifies poll outcomes because nothing below it does. The reader
honours IReadable literally — it throws only when the database is unreachable
and Bad-codes everything else — so a frozen database returns all-BadTimeout
snapshots through a perfectly successful PollGroupEngine tick. Without
ObservePollOutcome the driver would report Healthy while every value was Bad.
Connection-class codes (BadTimeout / BadCommunicationError) degrade health and
report the host Stopped; authoring-class codes (unresolvable RawPath, absent
row, type mismatch) change nothing, so a tag typo never reports the database
down. It deliberately does NOT synthesise an exception to earn engine backoff:
the engine's exception path publishes nothing, which would cost clients the
Bad quality the reader went out of its way to produce.
Initialize builds the authored RawPath table first (pure, cannot fail; a
malformed TagConfig is logged and skipped) then verifies liveness over one
open-use-dispose connection bounded by wall clock as well as by token (the
R2-01 lesson) — failure records Faulted and rethrows so DriverInstanceActor
retries. The connection string is never logged: a credential-free
server/database Endpoint is the only rendering that reaches a log, LastError,
or the host status.
DriverTypeNames.Sql is NOT added here — DriverTypeNamesGuardTests asserts
bidirectional parity with registered factories, so the constant must land with
the factory (Task 11). SqlDriver.DriverTypeName carries the string until then.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
LastValueCache bridges MQTT's subscribe-first push model to the OPC UA
server's polled IReadable.ReadAsync: the subscription path calls Update()
per RawPath, the read path calls Read(). Read never throws; an unseen
RawPath returns BadWaitingForInitialData (0x80320000) rather than an
exception or null, so a batch covering many references degrades per-ref
instead of failing wholesale.
Deviates from the plan's GoodNoData snippet: GoodNoData is reserved
repo-wide for "the historian window held no samples" (NullHistorianDataSource,
OtOpcUaNodeManager HistoryRead paths); BadWaitingForInitialData is the
established convention for "no live value observed yet" (CalculationDriver,
VirtualTagEngine, FOCAS, AddressSpaceApplier). Keyed by RawPath per the v3
driver-reference identity, not a topic/JSON-path-derived key.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Review follow-ups on MqttConnection (Task 3):
- Every certificate test asserted rejection, so the accept branch was
unreachable-by-regression. Adds a leaf genuinely issued by the pinned CA and
asserts acceptance.
- ValidateAgainstPinnedCa never seeded ChainPolicy.ExtraStore from the incoming
chain, so a leaf behind an intermediate delivered during the handshake failed
despite a legitimate path to the pinned root. Seeds from both the incoming
chain's elements and its ExtraStore; CustomRootTrust still means only the
pinned roots may terminate the chain.
- A DisposeAsync racing an in-flight connect escaped as an unclassified
exception; it now folds into ObjectDisposedException.
- Promotes the single-caller concurrency invariant into the type remarks, with
the accurate blast radius (a leaked live connection, not a benign throw).
Serialising the lifecycle remains Task 4's job.
- X509Chain.Build can throw; an exception escaping a TLS validation callback is
an opaque handshake crash, so it is caught and refused.
- Adds a connect-retry test (Task 4's reconnect loop reuses the instance) and a
disposed-then-connect test.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Task 2 review follow-up. The plan specified MqttEquipmentTagParser.TryParse(reference)
with def.Name = the TagConfig blob, and told us to mirror a type named
ModbusEquipmentTagParser. Both are plan defects:
- EquipmentTagRefResolver documents that a v3 driver reference "is now always a
RawPath" and that the blob-parse fallback is retired. Keying Name by the blob
would make OnDataChange publish under a reference that never matches the
RawPath-keyed fan-out in DriverHostActor - silently dead in production with
every unit test still green.
- ModbusEquipmentTagParser does not exist. The six sibling drivers all use
<Driver>TagDefinitionFactory.FromTagConfig(tagConfig, rawPath, out def).
Changes:
- Rename MqttEquipmentTagParser -> MqttTagDefinitionFactory; TryParse(reference,
out def) -> FromTagConfig(tagConfig, rawPath, out def) setting Name: rawPath,
matching ModbusTagDefinitionFactory's structure, param docs and guard order.
- Pin the identity contract with a dedicated test so a regression to blob-keying
goes red.
- Read qos with the same strictness as the enums: a present-but-invalid qos
("high" / 1.5 / 5 / null) now rejects the tag and is warned by Inspect,
instead of being silently absorbed into the driver-level default and handing
the operator a weaker delivery guarantee than the one they authored.
- No ToTagConfig inverse: the siblings carry one solely for their Driver.<X>.Cli
project, the MQTT plan defines none, and the AdminUI editor template
references no driver factory. Recorded as an explicit YAGNI call in the type
doc rather than added speculatively.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Code-review Minor: the record typed ParameterNames/Parameters/Members/
SelectedColumns as IReadOnlyList<T> but was handed the planner's live List<T>
instances. SqlQueryPlan documents itself as safe to hold for plan caching, so
an aliased list is a real hazard once the reader starts reusing plans across
polls: IReadOnlyList<T> is downcastable, and one mutation would corrupt every
subsequent poll served by that plan.
Copying at the record boundary fixes it for every call site at once rather
than relying on each planner branch remembering to call AsReadOnly.
Pinned by a test that mutates the caller's lists after construction; verified
load-bearing (reverting the record turns it red).
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Executes a poll pass: resolve refs -> SqlGroupPlanner.Plan -> one command per
group -> slice the result set back to per-tag DataValueSnapshots, positionally
aligned with the caller's reference list (design §3.2).
The frozen-peer contract (design §8.3, the R2-01 S7 lesson) is the core of it.
CommandTimeout is only the server-side backstop; the client-side bound is a
linked CancelAfter PLUS Task.WaitAsync, because a linked token bounds only a
provider that honours it and ADO.NET providers vary. The whole per-group
operation — waiting for a concurrency slot, OpenAsync, and the query — runs off
one operationTimeout budget, so ReadAsync returns on time regardless of what the
database is doing. A breach Bad-codes that group (BadTimeout); caller
cancellation propagates instead, since nobody consumes a torn-down poll.
Also: absent row (BadNoData) stays distinct from a NULL cell (Uncertain, or Bad
under nullIsBad); duplicate plan members are all fed (two tags on one keyValue
bind one parameter but stay two members); the concurrency slot is released by the
work, not the waiter, so a frozen database can never hold more than
maxConcurrentGroups connections; the whole call throws only when the connection
itself cannot open, which is what earns PollGroupEngine's backoff.
SqlStatusCodes is driver-local, matching every sibling driver's own table — there
is no shared helper in Core.Abstractions and drivers do not reference the OPC UA
SDK. Values were read off Opc.Ua.StatusCodes rather than copied from a sibling,
because two of those tables carry transcription errors.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Three findings from the code review of the dialect seam:
- QuoteIdentifier used char.IsControl, which only covers Unicode category Cc.
Bidi overrides, zero-width spaces, soft hyphen and BOM are category Cf and
passed through untouched. They cannot escape the brackets, so this is not an
injection bypass — but the method rejects control characters precisely to
protect the integrity of logged/audited statements, and Cf characters spoof
rendered text while comparing byte-different from the real catalog name
(Trojan Source, CVE-2021-42574). Same rule, same rationale, wider category.
- The XML docs on both files asserted that identifiers 'are sourced only from
catalog-validated (INFORMATION_SCHEMA) names' and that rejection is 'a
backstop, not the primary defence'. Neither is true yet: design §8.1 does
specify that gate, but nothing implements it and no task in the plan
schedules one, so an authored TagConfig table/column reaches QuoteIdentifier
unfiltered. The docs now say so, because under-scrutinising this method on
the strength of a filter that does not exist is exactly the failure mode.
- The control-character test only pinned NUL, so a regression to a
Contains('\0') check would still have passed. Pinned the whole Cc category
plus the new Cf rule; verified load-bearing by deleting the guard and
observing exactly the 5 new cases go red.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Code review of f22db5d8 (approved-with-findings): the existing round-trip
tests only exercised explicit JSON payloads, so nothing failed if UseTls /
AllowUntrustedServerCertificate or the §5.1 numeric defaults were flipped.
Adds a defaults-pinning test plus a partial-JSON test that omits the TLS
knobs entirely (the production case — an operator config that just doesn't
mention TLS must not silently land insecure).
Also overrides the record's PrintMembers so ToString() no longer prints
Password in plaintext (verified RED before the fix: the new test failed
with the raw password in the rendered string). OpcUaClientDriverOptions has
the same unredacted-ToString() shape but is out of scope for this task per
the coordinator's note; flagging as a possible follow-up.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
The dialect owns the two things ADO.NET's System.Data.Common base types
cannot abstract: identifier quoting and the metadata-catalog SQL. It is
the driver's SQL-injection boundary — values always bind as DbParameters,
identifiers cannot, so the few that reach a command text are catalog-
sourced and pass through QuoteIdentifier.
QuoteIdentifier brackets one identifier part and doubles embedded ] (the
only metacharacter that can terminate a bracketed identifier early);
rejects null/empty/whitespace, >128 chars (T-SQL sysname ceiling), and any
control character (incl. NUL) as ArgumentException, without echoing the
untrusted value into the message. MapColumnType folds the design §3.7
families case-insensitively and never throws — an unrecognised family
falls back to String so a browse over an exotic column still renders;
timestamp/rowversion and time are deliberately NOT mapped to DateTime.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Per-plan copy-paste command (subagent-driven-development in a git worktree),
plus the slash-command and executing-plans/resume alternatives, and a note that
the four independent plans can run in concurrent worktrees.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
ClusterPrimaryHealthCheck was written three days' worth of debugging ago because
the shared ActiveNodeHealthCheck selected by RoleLeader and reported Healthy for
any node lacking the role. Health 0.3.0 fixes the shared check — oldest Up
member, role-preference scoping, Unhealthy when the node owns no active work —
so the private copy is now duplication rather than a workaround, and it is
deleted.
RolePreference [admin, driver] reproduces exactly what it did: a fused central
node answers for admin (where the singletons and the AdminUI are pinned), a
driver-only site node answers for driver.
SelectOldestUpMemberOfRole now delegates to the shared ClusterActiveNode instead
of re-implementing the age ordering. This is the point of the change rather than
a tidy-up: the redundancy snapshot drives the OPC UA ServiceLevel 250/240 split
while the health tier drives Traefik's admin routing, so two copies of "oldest Up
member of a role" would be two chances to advertise one node as authoritative
while gating the data plane on another. ControlPlane takes a ZB.MOM.WW.Health.Akka
reference for it; the layering trade-off is recorded at the PackageReference.
Behaviour note: a node carrying neither admin nor driver now answers 503 on the
active tier instead of 200. That case is reachable — RoleParser admits dev-only
and cluster-role-only nodes — and 503 is correct, since such a node owns no
active work and must not be in an active-tier pool. No docker-dev node is
affected: every rig node is admin+driver or driver-only.
Tests replaced in kind. The rule itself is now pinned in the library against a
real two-node cluster; what stays OtOpcUa's own decision is the wiring, so
ActiveTierRegistrationTests pins which check is on the active tag, that it is
registered on driver-only nodes too, and that it is not on the ready tier.
Verified: Host.Tests 25/25, ControlPlane redundancy 15/15.
Add a living progress tracker (docs/plans/2026-07-24-driver-expansion-tracking.md)
for the driver-expansion program's Waves 0-2, linked from the program design doc's
document map. One row per deliverable pointing at design + implementation plan + status.
Add executable implementation plans (plan .md + co-located .tasks.json) for the four
Wave 1/2 drivers, each authored by writing-plans methodology off its design doc and
mirroring the relevant existing driver:
- Modbus RTU 11 tasks (extends Driver.Modbus; RTU-over-TCP, direct-serial descoped)
- SQL poll 22 tasks (ISqlDialect seam, SQL Server only in v1; SQLite + central-SQL fixtures)
- MTConnect Agent 23 tasks (browse free via Wave-0 seam; TrakHound-vs-hand-rolled = Task 0)
- MQTT/Sparkplug B 27 tasks (P1 plain MQTT 0-14 then P2 Sparkplug 15-26; MQTTnet-5 pinning spike = Task 0)
Wave 0 (universal browser) remains merged (056887d6) with its live gate open (#468).
All four new plans are design-only -> plan-ready; nothing built yet.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Closes the remaining half of #494, and corrects the half fixed in 8dd9da7d.
The shared ActiveNodeHealthCheck(role: "admin") answered the wrong question twice
over. It returns Healthy for any node LACKING the role, so all four driver-only
site nodes called themselves active and no consumer could find the Primary of a
site Cluster. And it selects by RoleLeader - the lowest-ADDRESSED member - which
is not where Akka places singletons.
Replaced with ClusterPrimaryHealthCheck ("cluster-primary"). One rule: this node
is active iff it is the OLDEST Up member carrying its own active role, where the
active role is admin when the node has it and driver otherwise. That serves both
consumers correctly - a fused admin node answers for admin, so Traefik pins the
AdminUI to the node hosting the singletons; a driver-only site node answers for
driver, which is exactly SelectDriverPrimary, the same election behind
IsDriverPrimary and the OPC UA ServiceLevel 250/240 split. Per-mesh scoping is
free after Phase 6: ClusterState.Members already contains only this node's own
Cluster.
SelectDriverPrimary is generalised to SelectOldestUpMemberOfRole so the
age-ordering rule has one implementation. Two copies of "oldest Up member of a
role" would be two chances to silently disagree about who is in charge, and the
tier and the redundancy snapshot must never disagree.
THE ROLE-LEADER HALF MATTERED IN PRACTICE, not just in theory. On the rebuilt rig
the two orderings diverge right now:
akka leader (lowest address) = central-1
oldest admin member = central-2 <- hosts the singletons
8dd9da7d made the tier a real 503 but still selected by RoleLeader, so it would
have pinned Traefik to central-1 - the node NOT hosting the work. With this change
Traefik correctly routes to central-2.
Live-verified, exactly one 200 per mesh:
MAIN central-2 200 central-1 503 traefik: central-2 UP, central-1 DOWN
SITE-A site-a-1 200 site-a-2 503
SITE-B site-b-1 200 site-b-2 503
Tests: role-selection matrix and the startup-safe Degraded path in Host.Tests
(26 pass); parity between the tier's selector and the redundancy snapshot's, plus
role scoping, added to RedundancyPrimaryElectionTests, which forms a real two-node
cluster deliberately built so the oldest member is not the lowest-addressed one
(5 pass).
0.2.1 makes the shared ActiveNodeHealthCheck return Unhealthy (503), not
Degraded (200), for a node that carries the role but is not the role leader.
That is what the shared health spec always specified, what docs/ServiceHosting.md,
docs/v2/Architecture-v2.md and the 2026-05-26 alignment design all describe
("200 only on the Admin-role leader; 503 elsewhere"), and what
docker-dev/traefik-dynamic.yml + scripts/install/traefik-dynamic.yml assume when
they use /health/active as the load-balancer probe.
The implementation returned Degraded, which MapZbHealth maps to 200, so BOTH
central nodes always passed the probe and Traefik load-balanced the admin UI
across the pair instead of pinning it to the leader. The docs were right; the
code was wrong. Closes the Traefik half of #494.
No OtOpcUa code change — package pin only.
Live-verified on docker-dev, with the MAIN pair genuinely formed (memberCount 2,
both members naming one leader):
central-1 (leader) /health/active -> 200 traefik UP
central-2 (standby) /health/active -> 503 traefik DOWN
Failover drill (README step 2), which had never actually exercised anything:
stopping central-1 flipped Traefik to central-2 within 20 s and
http://localhost:9200/ answered 200 continuously across the swap — no outage.
Restarting central-1 reclaimed the role-leader and Traefik flipped back.
README corrected on two counts: the drill now states that exactly ONE backend is
UP by design, and step 3 no longer claims central-2 keeps leadership — RoleLeader
is the lowest-address member, so central-1 deterministically reclaims it. Added
the cold-boot caveat that starting both nodes at once can leave each self-forming
a 1-member cluster, in which case both are their own leader and both answer 200.
STILL OPEN in #494: driver-only nodes. The check is scoped to the admin role and
returns Healthy for any node that lacks it, so all four site nodes answer 200 and
the real per-Cluster redundancy Primary (oldest Up driver member, IsDriverPrimary)
is still not what this tier reports.
Picks up the additive per-entry `data` object in the canonical health JSON and
the cluster-view data the shared AkkaClusterHealthCheck now publishes (leader /
selfAddress / selfRoles / memberCount / unreachableCount).
No OtOpcUa code change is needed: the "akka" ready/active check is already the
shared ZB.MOM.WW.Health.Akka.AkkaClusterHealthCheck (Health/HealthEndpoints.cs),
so /health/ready starts carrying entries["akka"].data.leader on the bump alone.
Payloads from every other check are byte-identical — data is emitted only when a
check publishes some.
Prereq for the family overview dashboard (scadaproj
docs/plans/2026-07-22-overview-dashboard-impl-plan.md, Phase 2).
Verified: Host 21/21, AdminUI 692/692, Host builds 0 warnings.
Live rig check (admin node serves data.leader) deferred to the dashboard's
acceptance run.
The simultaneous-cold-start split-brain, carried as a Phase 7 "candidate follow-up,
not shipped", is now closed by the opt-in Cluster:BootstrapGuard (279d1d0f). Documents
the guard in CLAUDE.md's bootstrap section and marks the Phase 7 finding closed.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Joseph Doherty