Polling chosen over event-driven for initial scope: simpler, matches Admin UI consumer cadence, avoids DriverHost lifecycle-event plumbing that doesn't exist today. Event-driven push for sub-heartbeat latency is a straightforward follow-up.
Admin.Services.HostStatusService left-joins DriverHostStatus against ClusterNode on NodeId so rows persist even when the ClusterNode entry doesn't exist yet (first-boot bootstrap case). StaleThreshold = 30s — covers one missed publisher heartbeat plus a generous buffer for clock skew and GC pauses. Admin Components/Pages/Hosts.razor — FleetAdmin-visible page grouped by cluster (handles the '(unassigned)' case for rows without a matching ClusterNode). Four summary cards (Hosts / Running / Stale / Faulted); per-cluster table with Node / Driver / Host / State + Stale-badge / Last-transition / Last-seen / Detail columns; 10s auto-refresh via IServiceScopeFactory timer pattern matching FleetStatusPoller + Fleet dashboard (PR 27). Row-class highlighting: Faulted → table-danger, Stale → table-warning, else default. State badge maps DriverHostState enum to bootstrap color classes. Sidebar link added between 'Fleet status' and 'Clusters'.
Server csproj adds Microsoft.EntityFrameworkCore.SqlServer 10.0.0 + registers OtOpcUaConfigDbContext in Program.cs scoped via NodeOptions.ConfigDbConnectionString (no Admin-style manual SQL raw — the DbContext is the only access path, keeps migrations owner-of-record).
Tests — HostStatusPublisherTests (4 new Integration cases, uses per-run throwaway DB matching the FleetStatusPollerTests pattern): publisher upserts one row per host from each probe-capable driver and skips non-probe drivers; second tick advances LastSeenUtc without creating duplicate rows (upsert pattern verified end-to-end); state change between ticks updates State AND StateChangedUtc (datetime2(3) rounds to millisecond precision so comparison uses 1ms tolerance — documented inline); MapState translates every HostState enum member. Server.Tests Integration: 4 new tests pass. Admin build clean, Admin.Tests Unit still 23 / 0. docs/v2/lmx-followups.md item #7 marked DONE with three explicit deferred items (event-driven push, failure-count column, SignalR fan-out).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Razor page layout: two tables (Rejected / Trusted) with Subject / Issuer / Thumbprint / Valid-window / Actions columns, status banner after each action with success or warning kind ('file missing' = another admin handled it), FleetAdmin-only via [Authorize(Roles=AdminRoles.FleetAdmin)]. Each action invokes LogActionAsync which Serilog-logs the authenticated admin user + thumbprint + action for an audit trail — DB-level ConfigAuditLog persistence is deferred because its schema is cluster-scoped and cert actions are cluster-agnostic; Serilog + CertTrustService's filesystem-op info logs give the forensic trail in the meantime. Sidebar link added to MainLayout between Reservations and the future Account page.
Tests — CertTrustServiceTests (9 new unit cases): ListRejected parses Subject + Thumbprint + store kind from a self-signed test cert written into rejected/certs/; rejected and trusted stores are kept separate; TrustRejected moves the file and the Rejected list is empty afterwards; TrustRejected with a thumbprint not in rejected returns false without touching trusted; DeleteRejected removes the file; UntrustCert removes from trusted only; thumbprint match is case-insensitive (operator UX); missing store directories produce empty lists instead of throwing DirectoryNotFoundException (pristine-install tolerance); a junk .der in the store is logged + skipped and the valid certs still surface (one bad file doesn't break the page). Full Admin.Tests Unit suite: 23 pass / 0 fail (14 prior + 9 new). Full Admin build clean — 0 errors, 0 warnings.
lmx-followups.md #3 marked DONE with a cross-reference to this PR and a note that flipping AutoAcceptUntrustedClientCertificates to false as the production default is a deployment-config follow-up, not a code gap — the Admin UI is now ready to be the trust gate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>