feat: Hub monitoring takeover — event system, dead man's switch, notifications (v0.3.0)

Replace external Healthchecks.io with Hub-native monitoring. New events
table + /api/v1/event endpoint for structured events from controllers.
Staleness checker (60s) detects unresponsive nodes. Backup deadline
checker (daily 05:00) catches missed backups. Notification dispatcher
sends operator (English) + customer (Hungarian) emails via Resend with
per-event cooldowns. Event timeline on customer page, dashboard badges.
Config form deprecates Monitoring UUIDs section.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

hub/CHANGELOG.md

@@ -1,5 +1,55 @@
 # Felhom Hub — Changelog
 
+## v0.3.0 (2026-02-20)
+
+**Hub Monitoring Takeover — Event System, Dead Man's Switch, Notifications**
+
+Replaces external Healthchecks.io with a Hub-native event system. The Hub becomes the single source of truth for all customer monitoring, event tracking, dead man's switch alerting, and notification delivery.
+
+### Phase 1 — Event System
+- **`events` table** in SQLite: stores all events with customer_id, event_type, severity, message, details_json, source, timestamp
+- **Indexes**: `idx_events_customer_created` (customer + time DESC), `idx_events_type` (type + time DESC)
+- **Store methods**: `SaveEvent`, `GetRecentEvents`, `GetEventsByType`, `GetLatestEventByType`, `GetAllRecentEvents`, `CountEventsBySeverity`, `PruneEvents`, `GetActiveCustomerIDs`
+- **`POST /api/v1/event`** endpoint: accepts structured events from controllers, validates event_type against 27 allowed types, validates severity (info/warning/error), stores in DB
+- **Enhanced auth**: `checkAuthCustomer()` validates per-customer API keys match the customer_id in payload; global key bypasses ownership check
+- **Prune**: events pruned alongside reports at 04:30 Budapest time
+
+### Phase 2 — Dead Man's Switch
+- **Staleness checker** (`internal/monitor/staleness.go`): runs every 60s, detects when controllers stop reporting
+  - ok→stale (>30min): inserts `node_stale` warning event
+  - any→down (>60min): inserts `node_down` error event
+  - stale/down→ok: inserts `node_recovered` info event
+  - Skips blocked customers, no false alerts on startup
+- **Backup deadline checker** (`internal/monitor/deadline.go`): runs daily at 05:00 Budapest
+  - Detects missing `backup_completed` events since midnight → inserts `expected_backup_missed` error
+  - Detects missing `db_dump_completed` events → inserts `expected_dbdump_missed` error
+  - Grace: skips customers with `node_down` state
+- **`scheduleDaily()`** helper: goroutine that sleeps until target time (Europe/Budapest), runs function, loops
+- **`/healthz`** enhanced: returns 503 if SQLite Ping fails
+
+### Phase 3 — Notification System
+- **Dispatcher** (`internal/notify/dispatcher.go`): processes events and sends emails via Resend API
+  - **Operator channel**: English emails to operator for warning/error events, 1h cooldown per customer:eventType
+  - **Customer channel**: Hungarian emails per event_type, respects customer preferences (enabled_events, cooldown_hours), blocked customers skipped
+  - **Test bypass**: `test` event type skips cooldown/preferences, sends directly to customer email
+- **Email templates** (`internal/notify/templates.go`): operator (concise English), customer (Hungarian per event type with complete message table)
+- **Cooldown tracking**: in-memory maps with per-customer:eventType granularity
+- **`customer_notifications` table**: added `cooldown_hours` column (default 6)
+- **`notification_log` table**: added `channel` column (operator/customer)
+- Wired into `/api/v1/event` handler and staleness/deadline checkers
+
+### Phase 4 — Hub UI
+- **Events section** on customer detail page: last 50 events, severity filter buttons (All/Errors/Warnings/Info), colored severity badges
+- **Dashboard badges**: error+warning count in last 24h per customer, clickable to customer events
+- **Notification log**: shows channel column (operator/customer) in customer detail page
+- **Config form**: Monitoring UUIDs section marked as "Legacy" with deprecation notice, collapsed by default
+
+### Phase 6 — Config Cleanup
+- **`controller.yaml.default`**: `monitoring.ping_uuids` section commented out (deprecated)
+- **`buildConfigJSON`**: only writes `ping_uuids` to config JSON if user explicitly provides UUID values (new configs get none)
+
+---
+
 ## v0.2.2 (2026-02-20)
 
 **Config Hash Comparison**

hub/README.md

@@ -2,9 +2,9 @@
 
 **Central operator dashboard for monitoring and managing Felhom customer deployments.**
 
-A lightweight Go service that receives periodic reports from felhom-controller instances, stores them in SQLite, and provides a web dashboard for fleet monitoring. Also serves as the infrastructure backup store for disaster recovery.
+A lightweight Go service that receives periodic reports and structured events from felhom-controller instances, stores them in SQLite, and provides a web dashboard for fleet monitoring. Also serves as the infrastructure backup store for disaster recovery, event-based dead man's switch monitoring, and notification dispatch.
 
-**Current version: v0.2.2**
+**Current version: v0.3.0**
 
 ---
 
@@ -72,14 +72,29 @@ The infra-backup payload contains everything needed to restore a customer deploy
 4. Controller uses disk UUIDs to auto-mount surviving drives
 5. Controller restores apps from local backups on those drives
 
+### Events
+
+| Method | Path | Description |
+|--------|------|-------------|
+| `POST` | `/api/v1/event` | Controller pushes structured event (27 allowed types, severity: info/warning/error) |
+
+Events are the primary monitoring mechanism. Each event has: customer_id, event_type, severity, message, details_json, source. Per-customer API keys are validated against the customer_id in the payload. Stored in the `events` table with automatic pruning.
+
+**Hub-generated events** (source="hub"):
+- `node_stale` / `node_down` / `node_recovered` — dead man's switch from staleness checker (every 60s)
+- `expected_backup_missed` / `expected_dbdump_missed` — backup deadline checker (daily at 05:00 Budapest)
+
 ### Notifications
 
 | Method | Path | Description |
 |--------|------|-------------|
-| `POST` | `/api/v1/notify` | Controller sends event notification (backup_failed, disk_warning, etc.) |
-| `POST` | `/api/v1/preferences` | Controller syncs customer notification preferences |
+| `POST` | `/api/v1/notify` | Legacy notification relay (kept for backward compatibility) |
+| `POST` | `/api/v1/preferences` | Controller syncs customer notification preferences (email, enabled_events, cooldown_hours) |
 
-Notifications are sent via Resend.com email API.
+Notifications are dispatched automatically when events are processed:
+- **Operator channel**: English emails for warning/error events, 1h cooldown per customer:eventType
+- **Customer channel**: Hungarian emails per event type, respects customer preferences and cooldown (default 6h)
+- Email delivery via Resend.com API
 
 ### Customer Config Retrieval
 
@@ -93,7 +108,7 @@ Config retrieval uses a separate per-customer retrieval password (not the API ke
 
 | Method | Path | Description |
 |--------|------|-------------|
-| `GET` | `/healthz` | Health check (no auth required) |
+| `GET` | `/healthz` | Health check (no auth required, returns 503 if SQLite ping fails) |
 
 ## Web Dashboard
 
@@ -101,13 +116,13 @@ Protected by bcrypt password + session cookie (7-day expiry).
 
 ### Pages
 
-- **Dashboard (`/`)** — Fleet overview table showing all customers with live status. Config-only customers (no reports yet) appear as "PENDING" with gray badge. Blocked customers are hidden. Auto-refreshes every 60 seconds.
+- **Dashboard (`/`)** — Fleet overview table showing all customers with live status and event count badges (error+warning in last 24h). Config-only customers (no reports yet) appear as "PENDING" with gray badge. Blocked customers are hidden. Auto-refreshes every 60 seconds.
 - **Customers (`/configs`)** — Customer management list. Shows all customers (both managed and manual), their status, controller version, and config type (MANAGED/MANUAL). Blocked customers shown grayed-out with BLOCKED badge.
 - **Unified Customer Detail (`/customers/{id}`)** — Single page per customer combining config management and live monitoring. Adapts content based on available data:
-  - **Managed + reporting:** Full view — config info, system metrics, storage, containers, backup status, credentials, setup commands, YAML preview, controller update, notifications, history
+  - **Managed + reporting:** Full view — config info, system metrics, storage, containers, backup status, events timeline (last 50, severity filter), credentials, setup commands, YAML preview, controller update, notifications (with channel column), history
   - **Managed + no reports yet:** Config info, credentials, setup commands, "Waiting for first report" indicator
   - **Manual (report-only):** System metrics, storage, containers, backup, with "Create Config" button to convert to managed
-- **Config Form (`/configs/new`, `/configs/{id}/edit`)** — Create/edit customer configurations with identity, infrastructure tokens, and monitoring overrides
+- **Config Form (`/configs/new`, `/configs/{id}/edit`)** — Create/edit customer configurations with identity, infrastructure tokens, and monitoring overrides. Legacy Monitoring UUIDs section collapsed by default with deprecation notice
 
 ### Customer States
 
@@ -144,9 +159,10 @@ SQLite with WAL mode. Tables:
 | Table | Purpose |
 |-------|---------|
 | `reports` | Full JSON reports with denormalized fields for dashboard queries |
+| `events` | Structured events from controllers and Hub (type, severity, message, details, source) |
 | `infra_backups` | Per-customer infrastructure snapshots for disaster recovery |
-| `customer_notifications` | Email + enabled event types per customer |
-| `notification_log` | Send/skip/fail history for notifications |
+| `customer_notifications` | Email, enabled event types, cooldown hours per customer |
+| `notification_log` | Send/skip/fail history for notifications with channel (operator/customer) |
 | `customer_configs` | Pre-configured customer settings, retrieval passwords, per-customer API keys, status (active/blocked) |
 
 Retention: configurable (default 90 days), daily prune at 04:30 Budapest time.
@@ -164,6 +180,8 @@ api:
 notifications:
   resend_api_key: ""          # Resend.com API key for email
   from_email: "monitoring@felhom.eu"
+  operator_email: ""          # Operator alert recipient
+  operator_enabled: true      # Enable operator email notifications
 
 retention:
   max_days: 90
@@ -195,16 +213,26 @@ Runs on k3s (Kubernetes) in the `felhom-system` namespace:
 ```bash
 # Build and push
 cd hub/
-make VERSION=0.2.2 docker docker-push
+make VERSION=0.3.0 docker docker-push
 
 # Deploy
-kubectl set image -n felhom-system deploy/hub hub=gitea.dooplex.hu/admin/felhom-hub:v0.2.2
+kubectl set image -n felhom-system deploy/hub hub=gitea.dooplex.hu/admin/felhom-hub:v0.3.0
 kubectl rollout status -n felhom-system deploy/hub
 
 # Check
 kubectl logs -n felhom-system -l app=hub --tail 20
 ```
 
+## Background Services
+
+| Service | Schedule | Description |
+|---------|----------|-------------|
+| **Staleness checker** | Every 60s | Detects controllers that stopped reporting. Generates `node_stale` (>30min), `node_down` (>60min), `node_recovered` events |
+| **Backup deadline checker** | Daily 05:00 Budapest | Detects missing backup/db-dump events since midnight. Generates `expected_backup_missed`, `expected_dbdump_missed` events |
+| **Report/event prune** | Daily 04:30 Budapest | Deletes reports and events older than retention period (default 90 days) |
+| **Registry version check** | Every 30min | Checks Gitea registry for new controller image tags |
+| **Template refresh** | Every 1h | Fetches latest `controller.yaml.example` from Gitea |
+
 ## Dependencies
 
 - `golang.org/x/crypto` — bcrypt for password hashing

hub/cmd/hub/main.go

@@ -13,6 +13,8 @@ import (
 	"time"
 
 	"gitea.dooplex.hu/admin/felhom-hub/internal/api"
+	"gitea.dooplex.hu/admin/felhom-hub/internal/monitor"
+	"gitea.dooplex.hu/admin/felhom-hub/internal/notify"
 	"gitea.dooplex.hu/admin/felhom-hub/internal/store"
 	"gitea.dooplex.hu/admin/felhom-hub/internal/web"
 	"gopkg.in/yaml.v3"
@@ -32,8 +34,10 @@ type Config struct {
 		ReportAPIKey string `yaml:"report_api_key"`
 	} `yaml:"api"`
 	Notifications struct {
-		ResendAPIKey string `yaml:"resend_api_key"`
-		FromEmail    string `yaml:"from_email"`
+		ResendAPIKey    string `yaml:"resend_api_key"`
+		FromEmail       string `yaml:"from_email"`
+		OperatorEmail   string `yaml:"operator_email"`
+		OperatorEnabled bool   `yaml:"operator_enabled"`
 	} `yaml:"notifications"`
 	Retention struct {
 		MaxDays       int    `yaml:"max_days"`
@@ -119,6 +123,18 @@ func main() {
 		templateProvider = templateFetcher
 	}
 	apiHandler := api.New(dataStore, cfg.API.ReportAPIKey, cfg.Notifications.ResendAPIKey, cfg.Notifications.FromEmail, templateProvider, logger)
+
+	// Initialize notification dispatcher
+	dispatcher := notify.NewDispatcher(
+		dataStore,
+		cfg.Notifications.ResendAPIKey,
+		cfg.Notifications.FromEmail,
+		cfg.Notifications.OperatorEmail,
+		cfg.Notifications.OperatorEnabled,
+		logger,
+	)
+	apiHandler.SetDispatcher(dispatcher)
+
 	webServer := web.New(dataStore, cfg.Auth.PasswordHash, cfg.API.ReportAPIKey, staleThreshold, logger)
 	webServer.SetTemplateFetcher(templateFetcher)
 
@@ -127,6 +143,11 @@ func main() {
 
 	// Health check endpoint — bypasses auth (for k8s probes)
 	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
+		if err := dataStore.Ping(); err != nil {
+			w.WriteHeader(http.StatusServiceUnavailable)
+			w.Write([]byte("db unhealthy"))
+			return
+		}
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte("ok"))
 	})
@@ -165,10 +186,34 @@ func main() {
 	}
 	webServer.SetVersionChecker(versionChecker)
 
+	// Prune on startup, then daily at configured time (default 04:30)
 	if cfg.Retention.MaxDays > 0 {
-		go pruneLoop(ctx, dataStore, cfg.Retention.MaxDays, logger)
+		pruneAll(dataStore, cfg.Retention.MaxDays, logger)
+		go scheduleDaily(ctx, "prune", cfg.Retention.PruneSchedule, func() {
+			pruneAll(dataStore, cfg.Retention.MaxDays, logger)
+		}, logger)
 	}
 
+	// Staleness checker — runs every 60s
+	stalenessChecker := monitor.NewStalenessChecker(dataStore, staleThreshold, dispatcher.ProcessEvent, logger)
+	go func() {
+		ticker := time.NewTicker(60 * time.Second)
+		defer ticker.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-ticker.C:
+				stalenessChecker.Check()
+			}
+		}
+	}()
+
+	// Backup deadline checker — runs daily at 05:00 Budapest
+	go scheduleDaily(ctx, "deadline-check", "05:00", func() {
+		monitor.CheckBackupDeadlines(dataStore, stalenessChecker, dispatcher.ProcessEvent, logger)
+	}, logger)
+
 	// Signal handling
 	sigCh := make(chan os.Signal, 1)
 	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
@@ -244,28 +289,52 @@ func loadConfig(path string, logger *log.Logger) *Config {
 	return cfg
 }
 
-func pruneLoop(ctx context.Context, s *store.Store, maxDays int, logger *log.Logger) {
-	// Prune once on startup
-	if deleted, err := s.Prune(maxDays); err != nil {
-		logger.Printf("[WARN] Prune failed: %v", err)
-	} else if deleted > 0 {
-		logger.Printf("[INFO] Pruned %d old report rows", deleted)
+// scheduleDaily runs fn once daily at the given "HH:MM" time in Europe/Budapest.
+// It blocks until ctx is cancelled.
+func scheduleDaily(ctx context.Context, name, timeStr string, fn func(), logger *log.Logger) {
+	budapest, err := time.LoadLocation("Europe/Budapest")
+	if err != nil {
+		budapest = time.FixedZone("CET", 3600)
 	}
 
-	// Then daily
-	ticker := time.NewTicker(24 * time.Hour)
-	defer ticker.Stop()
+	hour, min := parseHM(timeStr)
 
 	for {
+		now := time.Now().In(budapest)
+		next := time.Date(now.Year(), now.Month(), now.Day(), hour, min, 0, 0, budapest)
+		if !next.After(now) {
+			next = next.Add(24 * time.Hour)
+		}
+		delay := time.Until(next)
+		logger.Printf("[INFO] %s: next run at %s (in %s)", name, next.Format("2006-01-02 15:04 MST"), delay.Round(time.Second))
+
 		select {
 		case <-ctx.Done():
 			return
-		case <-ticker.C:
-			if deleted, err := s.Prune(maxDays); err != nil {
-				logger.Printf("[WARN] Prune failed: %v", err)
-			} else if deleted > 0 {
-				logger.Printf("[INFO] Pruned %d old report rows", deleted)
-			}
+		case <-time.After(delay):
+			fn()
 		}
 	}
 }
+
+// parseHM parses "HH:MM" into hour and minute. Returns 0, 0 on invalid input.
+func parseHM(s string) (int, int) {
+	var h, m int
+	if _, err := fmt.Sscanf(s, "%d:%d", &h, &m); err != nil {
+		return 0, 0
+	}
+	return h, m
+}
+
+func pruneAll(s *store.Store, maxDays int, logger *log.Logger) {
+	if deleted, err := s.Prune(maxDays); err != nil {
+		logger.Printf("[WARN] Prune reports failed: %v", err)
+	} else if deleted > 0 {
+		logger.Printf("[INFO] Pruned %d old report rows", deleted)
+	}
+	if deleted, err := s.PruneEvents(maxDays); err != nil {
+		logger.Printf("[WARN] Prune events failed: %v", err)
+	} else if deleted > 0 {
+		logger.Printf("[INFO] Pruned %d old event rows", deleted)
+	}
+}

hub/internal/api/handler.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"gitea.dooplex.hu/admin/felhom-hub/internal/configgen"
+	"gitea.dooplex.hu/admin/felhom-hub/internal/notify"
 	"gitea.dooplex.hu/admin/felhom-hub/internal/store"
 )
 
@@ -29,6 +30,7 @@ type Handler struct {
 	logger           *log.Logger
 	httpClient       *http.Client
 	templateProvider ConfigTemplateProvider
+	dispatcher       *notify.Dispatcher
 }
 
 // New creates a new API handler.
@@ -44,23 +46,40 @@ func New(store *store.Store, apiKey, resendAPIKey, fromEmail string, templatePro
 	}
 }
 
+// SetDispatcher sets the notification dispatcher for event-triggered emails.
+func (h *Handler) SetDispatcher(d *notify.Dispatcher) {
+	h.dispatcher = d
+}
+
 // checkAuth verifies the Bearer token against the global API key or a per-customer API key.
 // Returns true if authorized.
 func (h *Handler) checkAuth(r *http.Request) bool {
+	_, _, ok := h.checkAuthCustomer(r)
+	return ok
+}
+
+// checkAuthCustomer verifies the Bearer token and returns the authenticated customer identity.
+// For per-customer keys: returns (customerID, false, true).
+// For global key: returns ("", true, true) — caller must allow any customer_id.
+// On failure: returns ("", false, false).
+func (h *Handler) checkAuthCustomer(r *http.Request) (customerID string, isGlobal bool, ok bool) {
 	auth := r.Header.Get("Authorization")
 	if !strings.HasPrefix(auth, "Bearer ") {
-		return false
+		return "", false, false
 	}
 	token := strings.TrimPrefix(auth, "Bearer ")
 
 	// Check global key first
 	if h.apiKey != "" && subtle.ConstantTimeCompare([]byte(token), []byte(h.apiKey)) == 1 {
-		return true
+		return "", true, true
 	}
 
 	// Check per-customer key
 	cfg, err := h.store.GetCustomerConfigByAPIKey(token)
-	return err == nil && cfg != nil
+	if err != nil || cfg == nil {
+		return "", false, false
+	}
+	return cfg.CustomerID, false, true
 }
 
 // ServeHTTP routes API requests.
@@ -70,6 +89,8 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	switch {
 	case r.Method == http.MethodPost && path == "/report":
 		h.handleReport(w, r)
+	case r.Method == http.MethodPost && path == "/event":
+		h.handleEvent(w, r)
 	case r.Method == http.MethodPost && path == "/notify":
 		h.handleNotify(w, r)
 	case r.Method == http.MethodPost && path == "/infra-backup":
@@ -97,7 +118,8 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 func (h *Handler) handleReport(w http.ResponseWriter, r *http.Request) {
-	if !h.checkAuth(r) {
+	authCustomerID, isGlobal, ok := h.checkAuthCustomer(r)
+	if !ok {
 		http.Error(w, "Unauthorized", http.StatusUnauthorized)
 		return
 	}
@@ -117,6 +139,12 @@ func (h *Handler) handleReport(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Validate customer_id matches authenticated customer (unless global key)
+	if !isGlobal && authCustomerID != payload.CustomerID {
+		http.Error(w, "Forbidden: customer_id mismatch", http.StatusForbidden)
+		return
+	}
+
 	if err := h.store.SaveReport(payload.CustomerID, body); err != nil {
 		h.logger.Printf("[ERROR] Failed to save report from %s: %v", payload.CustomerID, err)
 		http.Error(w, "Internal error", http.StatusInternalServerError)
@@ -128,6 +156,114 @@ func (h *Handler) handleReport(w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte(`{"status":"ok"}`))
 }
 
+// allowedEventTypes lists all valid event_type values the Hub accepts.
+var allowedEventTypes = map[string]bool{
+	// Controller-pushed events
+	"controller_started":          true,
+	"controller_updated":          true,
+	"backup_completed":            true,
+	"backup_failed":               true,
+	"db_dump_completed":           true,
+	"db_dump_failed":              true,
+	"backup_integrity_ok":         true,
+	"backup_integrity_failed":     true,
+	"crossdrive_completed":        true,
+	"crossdrive_failed":           true,
+	"storage_disconnected":        true,
+	"storage_reconnected":         true,
+	"disk_warning":                true,
+	"disk_critical":               true,
+	"health_degraded":             true,
+	"health_critical":             true,
+	"health_recovered":            true,
+	"app_deployed":                true,
+	"app_removed":                 true,
+	"disaster_recovery_started":   true,
+	"disaster_recovery_completed": true,
+	// Hub-generated events
+	"node_stale":              true,
+	"node_down":               true,
+	"node_recovered":          true,
+	"expected_backup_missed":  true,
+	"expected_dbdump_missed":  true,
+	// Special
+	"test": true,
+}
+
+// handleEvent processes structured events from controllers (new endpoint, replaces /notify for updated controllers).
+func (h *Handler) handleEvent(w http.ResponseWriter, r *http.Request) {
+	authCustomerID, isGlobal, ok := h.checkAuthCustomer(r)
+	if !ok {
+		http.Error(w, "Unauthorized", http.StatusUnauthorized)
+		return
+	}
+
+	body, err := io.ReadAll(io.LimitReader(r.Body, 1<<20))
+	if err != nil {
+		http.Error(w, "Bad request", http.StatusBadRequest)
+		return
+	}
+
+	var payload struct {
+		CustomerID string          `json:"customer_id"`
+		EventType  string          `json:"event_type"`
+		Severity   string          `json:"severity"`
+		Message    string          `json:"message"`
+		Details    json.RawMessage `json:"details"`
+	}
+	if err := json.Unmarshal(body, &payload); err != nil {
+		http.Error(w, "Invalid JSON", http.StatusBadRequest)
+		return
+	}
+	if payload.CustomerID == "" || payload.EventType == "" {
+		http.Error(w, "customer_id and event_type are required", http.StatusBadRequest)
+		return
+	}
+
+	// Validate customer_id matches authenticated customer (unless global key)
+	if !isGlobal && authCustomerID != payload.CustomerID {
+		http.Error(w, "Forbidden: customer_id mismatch", http.StatusForbidden)
+		return
+	}
+
+	// Validate event_type
+	if !allowedEventTypes[payload.EventType] {
+		http.Error(w, fmt.Sprintf("Invalid event_type: %s", payload.EventType), http.StatusBadRequest)
+		return
+	}
+
+	// Validate/default severity
+	switch payload.Severity {
+	case "info", "warning", "error":
+	default:
+		payload.Severity = "info"
+	}
+
+	// Store details as JSON string
+	detailsStr := "{}"
+	if len(payload.Details) > 0 && string(payload.Details) != "null" {
+		detailsStr = string(payload.Details)
+	}
+
+	_, err = h.store.SaveEvent(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, detailsStr, "controller")
+	if err != nil {
+		h.logger.Printf("[ERROR] Failed to save event from %s: %v", payload.CustomerID, err)
+		http.Error(w, "Internal error", http.StatusInternalServerError)
+		return
+	}
+
+	h.logger.Printf("[INFO] Event from %s: %s (%s) — %s", payload.CustomerID, payload.EventType, payload.Severity, payload.Message)
+
+	// Dispatch notifications (non-blocking)
+	if h.dispatcher != nil {
+		go h.dispatcher.ProcessEvent(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, detailsStr, "controller")
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(`{"ok":true}`))
+}
+
 func (h *Handler) handleCustomers(w http.ResponseWriter, r *http.Request) {
 	customers, err := h.store.GetCustomers()
 	if err != nil {
@@ -258,7 +394,7 @@ func (h *Handler) handleNotify(w http.ResponseWriter, r *http.Request) {
 	// Check if customer is blocked
 	if h.store.IsCustomerBlocked(payload.CustomerID) {
 		h.logger.Printf("[INFO] Notification suppressed for blocked customer %s", payload.CustomerID)
-		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "customer blocked")
+		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "customer blocked", "customer")
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(`{"status":"ok","sent":false,"reason":"blocked"}`))
 		return
@@ -275,7 +411,7 @@ func (h *Handler) handleNotify(w http.ResponseWriter, r *http.Request) {
 	// Check if customer has email configured and event type is enabled
 	if prefs == nil || prefs.Email == "" {
 		h.logger.Printf("[INFO] No email configured for %s, skipping notification", payload.CustomerID)
-		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "no email configured")
+		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "no email configured", "customer")
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(`{"status":"ok","sent":false,"reason":"no_email"}`))
 		return
@@ -291,7 +427,7 @@ func (h *Handler) handleNotify(w http.ResponseWriter, r *http.Request) {
 	}
 	if !eventEnabled {
 		h.logger.Printf("[INFO] Event %s not enabled for %s, skipping", payload.EventType, payload.CustomerID)
-		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "event not enabled")
+		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "event not enabled", "customer")
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(`{"status":"ok","sent":false,"reason":"event_disabled"}`))
 		return
@@ -300,7 +436,7 @@ func (h *Handler) handleNotify(w http.ResponseWriter, r *http.Request) {
 	// Send email via Resend API
 	if h.resendAPIKey == "" {
 		h.logger.Printf("[WARN] Resend API key not configured, cannot send notification email")
-		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "resend api key not configured")
+		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "skipped", "resend api key not configured", "customer")
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(`{"status":"ok","sent":false,"reason":"no_api_key"}`))
 		return
@@ -310,13 +446,13 @@ func (h *Handler) handleNotify(w http.ResponseWriter, r *http.Request) {
 	sendErr := h.sendResendEmail(prefs.Email, subject, emailBody)
 	if sendErr != nil {
 		h.logger.Printf("[ERROR] Failed to send notification email to %s: %v", prefs.Email, sendErr)
-		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "failed", sendErr.Error())
+		h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "failed", sendErr.Error(), "customer")
 		http.Error(w, "Failed to send email", http.StatusInternalServerError)
 		return
 	}
 
 	h.logger.Printf("[INFO] Notification email sent to %s for %s/%s", prefs.Email, payload.CustomerID, payload.EventType)
-	h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "sent", "")
+	h.store.LogNotification(payload.CustomerID, payload.EventType, payload.Severity, payload.Message, "sent", "", "customer")
 
 	w.WriteHeader(http.StatusOK)
 	w.Write([]byte(`{"status":"ok","sent":true}`))
@@ -339,13 +475,14 @@ func (h *Handler) handleSavePreferences(w http.ResponseWriter, r *http.Request)
 		CustomerID    string   `json:"customer_id"`
 		Email         string   `json:"email"`
 		EnabledEvents []string `json:"enabled_events"`
+		CooldownHours int      `json:"cooldown_hours"`
 	}
 	if err := json.Unmarshal(body, &payload); err != nil || payload.CustomerID == "" {
 		http.Error(w, "Invalid payload: customer_id required", http.StatusBadRequest)
 		return
 	}
 
-	if err := h.store.SaveNotificationPrefs(payload.CustomerID, payload.Email, payload.EnabledEvents); err != nil {
+	if err := h.store.SaveNotificationPrefs(payload.CustomerID, payload.Email, payload.EnabledEvents, payload.CooldownHours); err != nil {
 		h.logger.Printf("[ERROR] Failed to save notification prefs for %s: %v", payload.CustomerID, err)
 		http.Error(w, "Internal error", http.StatusInternalServerError)
 		return
@@ -503,6 +640,7 @@ func formatNotificationEmail(customerID, eventType, severity, message, details s
 	severityLabel := map[string]string{
 		"info":     "Információ",
 		"warning":  "Figyelmeztetés",
+		"error":    "Hiba",
 		"critical": "Kritikus",
 	}
 	label := severityLabel[severity]

hub/internal/monitor/deadline.go

@@ -0,0 +1,86 @@
+package monitor
+
+import (
+	"log"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-hub/internal/store"
+)
+
+// budapest returns the Europe/Budapest timezone (cached).
+var budapest *time.Location
+
+func init() {
+	var err error
+	budapest, err = time.LoadLocation("Europe/Budapest")
+	if err != nil {
+		// Fallback: UTC+1 (CET base; DST handled by OS if available)
+		budapest = time.FixedZone("CET", 3600)
+	}
+}
+
+// CheckBackupDeadlines checks whether active customers had their expected
+// daily backups and DB dumps. Runs once daily at 05:00 Budapest time.
+//
+// For each active customer, it checks for backup_completed and db_dump_completed
+// events since Budapest midnight. If neither success nor failure events exist,
+// it inserts expected_backup_missed / expected_dbdump_missed events.
+//
+// Customers whose nodes are "down" (no report in >1h) are skipped — they
+// already have staleness events.
+func CheckBackupDeadlines(s *store.Store, staleness *StalenessChecker, onEvent EventNotifyFunc, logger *log.Logger) {
+	customerIDs, err := s.GetActiveCustomerIDs()
+	if err != nil {
+		logger.Printf("[WARN] Deadline check: failed to get active customers: %v", err)
+		return
+	}
+
+	// Budapest midnight today
+	now := time.Now().In(budapest)
+	midnightBudapest := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, budapest)
+	sinceUTC := midnightBudapest.UTC()
+
+	var backupMissed, dbdumpMissed, skipped int
+
+	for _, id := range customerIDs {
+		// Skip nodes that are down — they already have staleness events
+		if staleness != nil && staleness.GetState(id) == "down" {
+			skipped++
+			continue
+		}
+
+		// Check blocked
+		if s.IsCustomerBlocked(id) {
+			continue
+		}
+
+		// Check backup_completed / backup_failed since midnight
+		backupOK, _ := s.GetEventsByType(id, "backup_completed", sinceUTC)
+		backupFailed, _ := s.GetEventsByType(id, "backup_failed", sinceUTC)
+		if len(backupOK) == 0 && len(backupFailed) == 0 {
+			msg := "No backup completed or failed since midnight"
+			if _, err := s.SaveEvent(id, "expected_backup_missed", "error", msg, "{}", "hub"); err != nil {
+				logger.Printf("[WARN] Failed to save expected_backup_missed for %s: %v", id, err)
+			} else if onEvent != nil {
+				onEvent(id, "expected_backup_missed", "error", msg, "{}", "hub")
+			}
+			backupMissed++
+		}
+
+		// Check db_dump_completed / db_dump_failed since midnight
+		dumpOK, _ := s.GetEventsByType(id, "db_dump_completed", sinceUTC)
+		dumpFailed, _ := s.GetEventsByType(id, "db_dump_failed", sinceUTC)
+		if len(dumpOK) == 0 && len(dumpFailed) == 0 {
+			msg := "No DB dump completed or failed since midnight"
+			if _, err := s.SaveEvent(id, "expected_dbdump_missed", "error", msg, "{}", "hub"); err != nil {
+				logger.Printf("[WARN] Failed to save expected_dbdump_missed for %s: %v", id, err)
+			} else if onEvent != nil {
+				onEvent(id, "expected_dbdump_missed", "error", msg, "{}", "hub")
+			}
+			dbdumpMissed++
+		}
+	}
+
+	logger.Printf("[INFO] Deadline check: %d customers, %d backup missed, %d dbdump missed, %d skipped (down)",
+		len(customerIDs), backupMissed, dbdumpMissed, skipped)
+}

hub/internal/monitor/staleness.go

@@ -0,0 +1,183 @@
+package monitor
+
+import (
+	"fmt"
+	"log"
+	"sync"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-hub/internal/store"
+)
+
+// EventNotifyFunc is called after a hub-generated event is saved,
+// to trigger notification dispatch. Keeps monitor decoupled from notify.
+type EventNotifyFunc func(customerID, eventType, severity, message, detailsJSON, source string)
+
+// StalenessChecker monitors customer report freshness and generates
+// node_stale / node_down / node_recovered events on state transitions.
+type StalenessChecker struct {
+	store     *store.Store
+	threshold time.Duration // "stale" after this duration (default 30m)
+	downAfter time.Duration // "down" after this duration (2x threshold)
+	logger    *log.Logger
+	onEvent   EventNotifyFunc
+
+	mu     sync.Mutex
+	states map[string]string // customerID → "ok" | "stale" | "down"
+}
+
+// NewStalenessChecker creates a checker and initializes state from current data.
+// No events are generated during initialization (binding #12).
+// onEvent is called after each hub-generated event is saved (may be nil).
+func NewStalenessChecker(s *store.Store, threshold time.Duration, onEvent EventNotifyFunc, logger *log.Logger) *StalenessChecker {
+	sc := &StalenessChecker{
+		store:     s,
+		threshold: threshold,
+		downAfter: 2 * threshold,
+		logger:    logger,
+		onEvent:   onEvent,
+		states:    make(map[string]string),
+	}
+
+	// Seed states from current report timestamps — no events on init
+	customers, err := s.GetCustomers()
+	if err != nil {
+		logger.Printf("[WARN] Staleness checker: failed to seed states: %v", err)
+		return sc
+	}
+
+	var okCount, staleCount, downCount int
+	for _, c := range customers {
+		if s.IsCustomerBlocked(c.CustomerID) {
+			continue
+		}
+		age := time.Since(c.ReceivedAt)
+		switch {
+		case age > sc.downAfter:
+			sc.states[c.CustomerID] = "down"
+			downCount++
+		case age > sc.threshold:
+			sc.states[c.CustomerID] = "stale"
+			staleCount++
+		default:
+			sc.states[c.CustomerID] = "ok"
+			okCount++
+		}
+	}
+	logger.Printf("[INFO] Staleness checker initialized: %d ok, %d stale, %d down", okCount, staleCount, downCount)
+
+	return sc
+}
+
+// Check evaluates all customers and emits events on state transitions.
+// Should be called periodically (every 60s).
+func (sc *StalenessChecker) Check() {
+	customers, err := sc.store.GetCustomers()
+	if err != nil {
+		sc.logger.Printf("[WARN] Staleness check failed: %v", err)
+		return
+	}
+
+	sc.mu.Lock()
+	defer sc.mu.Unlock()
+
+	// Track which customers are still present (to clean up removed ones)
+	seen := make(map[string]bool, len(customers))
+
+	for _, c := range customers {
+		seen[c.CustomerID] = true
+
+		if sc.store.IsCustomerBlocked(c.CustomerID) {
+			delete(sc.states, c.CustomerID)
+			continue
+		}
+
+		age := time.Since(c.ReceivedAt)
+		var newState string
+		switch {
+		case age > sc.downAfter:
+			newState = "down"
+		case age > sc.threshold:
+			newState = "stale"
+		default:
+			newState = "ok"
+		}
+
+		oldState := sc.states[c.CustomerID]
+		if oldState == "" {
+			// New customer — set state without event
+			sc.states[c.CustomerID] = newState
+			continue
+		}
+
+		if oldState == newState {
+			continue
+		}
+
+		// State transition — emit event
+		sc.states[c.CustomerID] = newState
+		sc.emitTransition(c.CustomerID, oldState, newState, age)
+	}
+
+	// Clean up customers that no longer have reports
+	for id := range sc.states {
+		if !seen[id] {
+			delete(sc.states, id)
+		}
+	}
+}
+
+// GetState returns the current staleness state for a customer.
+func (sc *StalenessChecker) GetState(customerID string) string {
+	sc.mu.Lock()
+	defer sc.mu.Unlock()
+	s := sc.states[customerID]
+	if s == "" {
+		return "unknown"
+	}
+	return s
+}
+
+func (sc *StalenessChecker) emitTransition(customerID, oldState, newState string, age time.Duration) {
+	var eventType, severity, message string
+
+	switch {
+	case newState == "stale":
+		eventType = "node_stale"
+		severity = "warning"
+		message = "No report received for " + formatDuration(age)
+	case newState == "down":
+		eventType = "node_down"
+		severity = "error"
+		message = "No report received for " + formatDuration(age)
+	case newState == "ok" && (oldState == "stale" || oldState == "down"):
+		eventType = "node_recovered"
+		severity = "info"
+		message = "Reports resumed (was " + oldState + " for " + formatDuration(age) + ")"
+	default:
+		return
+	}
+
+	sc.logger.Printf("[INFO] Staleness: %s %s → %s (%s)", customerID, oldState, newState, eventType)
+
+	if _, err := sc.store.SaveEvent(customerID, eventType, severity, message, "{}", "hub"); err != nil {
+		sc.logger.Printf("[WARN] Failed to save staleness event for %s: %v", customerID, err)
+		return
+	}
+
+	if sc.onEvent != nil {
+		sc.onEvent(customerID, eventType, severity, message, "{}", "hub")
+	}
+}
+
+func formatDuration(d time.Duration) string {
+	if d < time.Hour {
+		return fmt.Sprintf("%dm", int(d.Minutes()))
+	}
+	h := int(d.Hours())
+	m := int(d.Minutes()) % 60
+	if m == 0 {
+		return fmt.Sprintf("%dh", h)
+	}
+	return fmt.Sprintf("%dh%dm", h, m)
+}

hub/internal/notify/dispatcher.go

@@ -0,0 +1,201 @@
+package notify
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"sync"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-hub/internal/store"
+)
+
+// Dispatcher routes events to operator and/or customer email channels.
+// Cooldowns are in-memory (lost on restart, acceptable).
+type Dispatcher struct {
+	store         *store.Store
+	resendAPIKey  string
+	fromEmail     string
+	operatorEmail string
+	operatorOn    bool
+	httpClient    *http.Client
+	logger        *log.Logger
+
+	mu            sync.Mutex
+	opCooldowns   map[string]time.Time // "customerID:eventType" → last operator notify
+	custCooldowns map[string]time.Time // "customerID:eventType" → last customer notify
+}
+
+// NewDispatcher creates a new notification dispatcher.
+func NewDispatcher(s *store.Store, resendAPIKey, fromEmail, operatorEmail string, operatorOn bool, logger *log.Logger) *Dispatcher {
+	return &Dispatcher{
+		store:         s,
+		resendAPIKey:  resendAPIKey,
+		fromEmail:     fromEmail,
+		operatorEmail: operatorEmail,
+		operatorOn:    operatorOn,
+		httpClient:    &http.Client{Timeout: 10 * time.Second},
+		logger:        logger,
+		opCooldowns:   make(map[string]time.Time),
+		custCooldowns: make(map[string]time.Time),
+	}
+}
+
+// ProcessEvent evaluates an event and sends notifications as appropriate.
+// Safe to call from goroutines.
+func (d *Dispatcher) ProcessEvent(customerID, eventType, severity, message, detailsJSON, source string) {
+	if d.resendAPIKey == "" {
+		return
+	}
+
+	// "test" bypass — send directly to customer email, skip prefs/cooldown
+	if eventType == "test" {
+		d.sendTestEmail(customerID)
+		return
+	}
+
+	// Only warning and error severity trigger notifications
+	if severity != "warning" && severity != "error" {
+		return
+	}
+
+	// Operator channel
+	d.processOperator(customerID, eventType, severity, message, detailsJSON, source)
+
+	// Customer channel
+	d.processCustomer(customerID, eventType, severity, message, detailsJSON, source)
+}
+
+func (d *Dispatcher) sendTestEmail(customerID string) {
+	prefs, err := d.store.GetNotificationPrefs(customerID)
+	if err != nil || prefs.Email == "" {
+		d.logger.Printf("[WARN] Test email: no email configured for %s", customerID)
+		return
+	}
+
+	subject := "[Felhom] Teszt értesítés"
+	body := "Kedves Ügyfél!\n\nEz egy teszt értesítés a Felhom monitoring rendszerből.\nAz értesítések megfelelően működnek.\n\nÜdvözlettel,\nFelhom.eu monitoring"
+
+	if err := d.sendEmail(prefs.Email, subject, body); err != nil {
+		d.logger.Printf("[ERROR] Test email to %s failed: %v", prefs.Email, err)
+		d.store.LogNotification(customerID, "test", "info", "Teszt értesítés", "failed", err.Error(), "customer")
+		return
+	}
+	d.logger.Printf("[INFO] Test email sent to %s for %s", prefs.Email, customerID)
+	d.store.LogNotification(customerID, "test", "info", "Teszt értesítés", "sent", "", "customer")
+}
+
+func (d *Dispatcher) processOperator(customerID, eventType, severity, message, detailsJSON, source string) {
+	if !d.operatorOn || d.operatorEmail == "" {
+		return
+	}
+
+	cooldownKey := customerID + ":" + eventType
+	d.mu.Lock()
+	if last, ok := d.opCooldowns[cooldownKey]; ok && time.Since(last) < 1*time.Hour {
+		d.mu.Unlock()
+		return
+	}
+	d.opCooldowns[cooldownKey] = time.Now()
+	d.mu.Unlock()
+
+	subject, body := FormatOperatorEmail(customerID, eventType, severity, message, detailsJSON)
+
+	if err := d.sendEmail(d.operatorEmail, subject, body); err != nil {
+		d.logger.Printf("[ERROR] Operator email failed for %s/%s: %v", customerID, eventType, err)
+		d.store.LogNotification(customerID, eventType, severity, message, "failed", err.Error(), "operator")
+		return
+	}
+	d.logger.Printf("[INFO] Operator email sent for %s/%s", customerID, eventType)
+	d.store.LogNotification(customerID, eventType, severity, message, "sent", "", "operator")
+}
+
+func (d *Dispatcher) processCustomer(customerID, eventType, severity, message, detailsJSON, source string) {
+	// Check if customer is blocked
+	if d.store.IsCustomerBlocked(customerID) {
+		return
+	}
+
+	// Load preferences
+	prefs, err := d.store.GetNotificationPrefs(customerID)
+	if err != nil || prefs.Email == "" {
+		return
+	}
+
+	// Check if event type is enabled
+	if !isEventEnabled(prefs.EnabledEvents, eventType) {
+		return
+	}
+
+	// Customer cooldown (from prefs, default 6h)
+	cooldownHours := prefs.CooldownHours
+	if cooldownHours <= 0 {
+		cooldownHours = 6
+	}
+	cooldownDur := time.Duration(cooldownHours) * time.Hour
+
+	cooldownKey := customerID + ":" + eventType
+	d.mu.Lock()
+	if last, ok := d.custCooldowns[cooldownKey]; ok && time.Since(last) < cooldownDur {
+		d.mu.Unlock()
+		return
+	}
+	d.custCooldowns[cooldownKey] = time.Now()
+	d.mu.Unlock()
+
+	subject, body := FormatCustomerEmail(customerID, eventType, severity, message, detailsJSON)
+
+	if err := d.sendEmail(prefs.Email, subject, body); err != nil {
+		d.logger.Printf("[ERROR] Customer email failed for %s/%s: %v", customerID, eventType, err)
+		d.store.LogNotification(customerID, eventType, severity, message, "failed", err.Error(), "customer")
+		return
+	}
+	d.logger.Printf("[INFO] Customer email sent to %s for %s/%s", prefs.Email, customerID, eventType)
+	d.store.LogNotification(customerID, eventType, severity, message, "sent", "", "customer")
+}
+
+func (d *Dispatcher) sendEmail(to, subject, textBody string) error {
+	payload := map[string]interface{}{
+		"from":    d.fromEmail,
+		"to":      []string{to},
+		"subject": subject,
+		"text":    textBody,
+	}
+
+	jsonData, err := json.Marshal(payload)
+	if err != nil {
+		return fmt.Errorf("marshaling email payload: %w", err)
+	}
+
+	req, err := http.NewRequest("POST", "https://api.resend.com/emails", bytes.NewReader(jsonData))
+	if err != nil {
+		return fmt.Errorf("creating request: %w", err)
+	}
+	req.Header.Set("Authorization", "Bearer "+d.resendAPIKey)
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := d.httpClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("sending request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		respBody, _ := io.ReadAll(io.LimitReader(resp.Body, 1024))
+		return fmt.Errorf("resend API returned %d: %s", resp.StatusCode, string(respBody))
+	}
+
+	return nil
+}
+
+func isEventEnabled(enabledEvents []string, eventType string) bool {
+	for _, e := range enabledEvents {
+		if e == eventType {
+			return true
+		}
+	}
+	return false
+}

hub/internal/notify/templates.go

@@ -0,0 +1,153 @@
+package notify
+
+import (
+	"fmt"
+	"time"
+)
+
+// budapest timezone for formatting.
+var budapest *time.Location
+
+func init() {
+	var err error
+	budapest, err = time.LoadLocation("Europe/Budapest")
+	if err != nil {
+		budapest = time.FixedZone("CET", 3600)
+	}
+}
+
+// ──────────────────────────────────────────────────────────────────────
+// Operator email — concise, English
+// ──────────────────────────────────────────────────────────────────────
+
+// FormatOperatorEmail returns (subject, textBody) for the operator channel.
+func FormatOperatorEmail(customerID, eventType, severity, message, detailsJSON string) (string, string) {
+	icon := "⚠️"
+	if severity == "error" {
+		icon = "🔴"
+	}
+
+	subject := fmt.Sprintf("[Felhom] %s %s: %s", icon, customerID, eventType)
+
+	now := time.Now().In(budapest).Format("2006-01-02 15:04 MST")
+	body := fmt.Sprintf(`Customer: %s
+Event:    %s
+Severity: %s
+Time:     %s
+Message:  %s`, customerID, eventType, severity, now, message)
+
+	if detailsJSON != "" && detailsJSON != "{}" {
+		body += fmt.Sprintf("\nDetails:  %s", detailsJSON)
+	}
+
+	body += fmt.Sprintf("\n\nDashboard: https://hub.felhom.eu/customers/%s", customerID)
+
+	return subject, body
+}
+
+// ──────────────────────────────────────────────────────────────────────
+// Customer email — Hungarian, friendly
+// ──────────────────────────────────────────────────────────────────────
+
+// customerMessages maps event_type → Hungarian customer message.
+var customerMessages = map[string]string{
+	// Backup events
+	"backup_completed":          "A biztonsági mentés sikeresen elkészült.",
+	"backup_failed":             "A biztonsági mentés sikertelen! Kérjük, ellenőrizd a rendszert.",
+	"db_dump_completed":         "Az adatbázis mentés sikeresen elkészült.",
+	"db_dump_failed":            "Az adatbázis mentés sikertelen!",
+	"backup_integrity_ok":       "A mentés integritás ellenőrzés sikeres.",
+	"backup_integrity_failed":   "A mentés integritás ellenőrzés hibát talált!",
+	"crossdrive_completed":      "A másodlagos mentés sikeresen elkészült.",
+	"crossdrive_failed":         "A másodlagos mentés sikertelen!",
+
+	// Disk events
+	"disk_warning":  "A lemezterület 90% felett van — kérjük, szabadíts fel helyet.",
+	"disk_critical": "A lemezterület kritikusan magas (95%+) — azonnali beavatkozás szükséges!",
+
+	// Storage events
+	"storage_disconnected": "Egy meghajtó leválasztva — a mentések szünetelhetnek.",
+	"storage_reconnected":  "A meghajtó újra csatlakoztatva.",
+
+	// Staleness events (Hub-generated)
+	"node_stale":     "A szerver nem küldött jelentést az elmúlt időszakban.",
+	"node_down":      "A szerver nem elérhető!",
+	"node_recovered": "A szerver újra elérhető.",
+
+	// Health events
+	"health_degraded":  "A rendszer állapota romlott.",
+	"health_critical":  "A rendszer állapota kritikus!",
+	"health_recovered": "A rendszer állapota helyreállt.",
+
+	// Controller events
+	"controller_started": "A vezérlő elindult.",
+	"controller_updated": "A vezérlő frissítve lett.",
+
+	// Deadline events (Hub-generated)
+	"expected_backup_missed": "A mai biztonsági mentés nem készült el a határidőig!",
+	"expected_dbdump_missed": "A mai adatbázis mentés nem készült el a határidőig!",
+
+	// App lifecycle events
+	"app_deployed": "Alkalmazás telepítve.",
+	"app_removed":  "Alkalmazás eltávolítva.",
+
+	// Disaster recovery events
+	"disaster_recovery_started":   "Katasztrófa helyreállítás elindítva.",
+	"disaster_recovery_completed": "Katasztrófa helyreállítás befejezve.",
+
+	// Test
+	"test": "Ez egy teszt értesítés.",
+}
+
+// severityLabels maps severity to Hungarian labels.
+var severityLabels = map[string]string{
+	"info":    "Információ",
+	"warning": "Figyelmeztetés",
+	"error":   "Hiba",
+}
+
+// FormatCustomerEmail returns (subject, textBody) for the customer channel.
+func FormatCustomerEmail(customerID, eventType, severity, message, detailsJSON string) (string, string) {
+	label := severityLabels[severity]
+	if label == "" {
+		label = severity
+	}
+
+	// Use the per-event-type Hungarian message if available, otherwise fall back to message
+	hunMessage := customerMessages[eventType]
+	if hunMessage == "" {
+		hunMessage = message
+	}
+
+	subject := fmt.Sprintf("[Felhom] %s: %s", label, hunMessage)
+
+	now := time.Now().In(budapest).Format("2006-01-02 15:04")
+	body := fmt.Sprintf(`Kedves Ügyfél!
+
+A Felhom rendszered a következő értesítést küldte:
+
+%s
+
+Részletek:
+- Szerver: %s
+- Időpont: %s
+- Szint: %s
+- Típus: %s`, hunMessage, customerID, now, label, eventType)
+
+	if message != "" && message != hunMessage {
+		body += fmt.Sprintf("\n- Üzenet: %s", message)
+	}
+
+	if detailsJSON != "" && detailsJSON != "{}" {
+		body += fmt.Sprintf("\n- Megjegyzés: %s", detailsJSON)
+	}
+
+	body += `
+
+Ha kérdésed van, vedd fel a kapcsolatot az üzemeltetővel.
+
+Üdvözlettel,
+Felhom.eu monitoring`
+
+	return subject, body
+}

hub/internal/store/store.go

@@ -121,6 +121,33 @@ func (s *Store) migrate() error {
 	// v0.2.1: add status column to customer_configs (idempotent)
 	s.db.Exec("ALTER TABLE customer_configs ADD COLUMN status TEXT NOT NULL DEFAULT 'active'")
 
+	// v0.3.0: events table for hub-native monitoring
+	_, err = s.db.Exec(`
+		CREATE TABLE IF NOT EXISTS events (
+			id INTEGER PRIMARY KEY AUTOINCREMENT,
+			customer_id TEXT NOT NULL,
+			event_type TEXT NOT NULL,
+			severity TEXT NOT NULL DEFAULT 'info',
+			message TEXT NOT NULL DEFAULT '',
+			details_json TEXT NOT NULL DEFAULT '{}',
+			source TEXT NOT NULL DEFAULT 'controller',
+			created_at DATETIME NOT NULL DEFAULT (datetime('now'))
+		);
+		CREATE INDEX IF NOT EXISTS idx_events_customer_created
+			ON events(customer_id, created_at DESC);
+		CREATE INDEX IF NOT EXISTS idx_events_type
+			ON events(event_type, created_at DESC);
+	`)
+	if err != nil {
+		return err
+	}
+
+	// v0.3.0: add cooldown_hours to customer_notifications (idempotent)
+	s.db.Exec("ALTER TABLE customer_notifications ADD COLUMN cooldown_hours INTEGER DEFAULT 6")
+
+	// v0.3.0: add channel column to notification_log (idempotent)
+	s.db.Exec("ALTER TABLE notification_log ADD COLUMN channel TEXT NOT NULL DEFAULT 'customer'")
+
 	return nil
 }
 
@@ -129,15 +156,17 @@ type NotificationPrefs struct {
 	CustomerID    string
 	Email         string
 	EnabledEvents []string
+	CooldownHours int
 }
 
 // GetNotificationPrefs returns notification preferences for a customer.
 func (s *Store) GetNotificationPrefs(customerID string) (*NotificationPrefs, error) {
 	var email, eventsJSON string
+	var cooldownHours int
 	err := s.db.QueryRow(
-		"SELECT email, enabled_events FROM customer_notifications WHERE customer_id = ?",
+		"SELECT email, enabled_events, COALESCE(cooldown_hours, 6) FROM customer_notifications WHERE customer_id = ?",
 		customerID,
-	).Scan(&email, &eventsJSON)
+	).Scan(&email, &eventsJSON, &cooldownHours)
 	if err != nil {
 		if err == sql.ErrNoRows {
 			return nil, nil
@@ -150,34 +179,46 @@ func (s *Store) GetNotificationPrefs(customerID string) (*NotificationPrefs, err
 		s.logger.Printf("[WARN] Corrupt enabled_events JSON for %s: %v", customerID, err)
 	}
 
+	if cooldownHours <= 0 {
+		cooldownHours = 6
+	}
+
 	return &NotificationPrefs{
 		CustomerID:    customerID,
 		Email:         email,
 		EnabledEvents: events,
+		CooldownHours: cooldownHours,
 	}, nil
 }
 
 // SaveNotificationPrefs creates or updates notification preferences for a customer.
-func (s *Store) SaveNotificationPrefs(customerID, email string, enabledEvents []string) error {
+func (s *Store) SaveNotificationPrefs(customerID, email string, enabledEvents []string, cooldownHours int) error {
 	eventsJSON, _ := json.Marshal(enabledEvents)
+	if cooldownHours <= 0 {
+		cooldownHours = 6
+	}
 	_, err := s.db.Exec(`
-		INSERT INTO customer_notifications (customer_id, email, enabled_events, updated_at)
-		VALUES (?, ?, ?, datetime('now'))
+		INSERT INTO customer_notifications (customer_id, email, enabled_events, cooldown_hours, updated_at)
+		VALUES (?, ?, ?, ?, datetime('now'))
 		ON CONFLICT(customer_id) DO UPDATE SET
 			email = excluded.email,
 			enabled_events = excluded.enabled_events,
+			cooldown_hours = excluded.cooldown_hours,
 			updated_at = datetime('now')`,
-		customerID, email, string(eventsJSON),
+		customerID, email, string(eventsJSON), cooldownHours,
 	)
 	return err
 }
 
 // LogNotification records a notification attempt.
-func (s *Store) LogNotification(customerID, eventType, severity, message, status, errorMsg string) error {
+func (s *Store) LogNotification(customerID, eventType, severity, message, status, errorMsg, channel string) error {
+	if channel == "" {
+		channel = "customer"
+	}
 	_, err := s.db.Exec(`
-		INSERT INTO notification_log (customer_id, event_type, severity, message, status, error_message)
-		VALUES (?, ?, ?, ?, ?, ?)`,
-		customerID, eventType, severity, message, status, errorMsg,
+		INSERT INTO notification_log (customer_id, event_type, severity, message, status, error_message, channel)
+		VALUES (?, ?, ?, ?, ?, ?, ?)`,
+		customerID, eventType, severity, message, status, errorMsg, channel,
 	)
 	return err
 }
@@ -189,13 +230,14 @@ type NotificationLogEntry struct {
 	Message      string
 	Status       string // "sent", "skipped", "failed"
 	ErrorMessage string
+	Channel      string // "operator" or "customer"
 	CreatedAt    time.Time
 }
 
 // GetRecentNotifications returns the most recent notification log entries for a customer.
 func (s *Store) GetRecentNotifications(customerID string, limit int) ([]NotificationLogEntry, error) {
 	rows, err := s.db.Query(`
-		SELECT event_type, severity, message, status, COALESCE(error_message, ''), created_at
+		SELECT event_type, severity, message, status, COALESCE(error_message, ''), COALESCE(channel, 'customer'), created_at
 		FROM notification_log
 		WHERE customer_id = ?
 		ORDER BY created_at DESC
@@ -209,7 +251,7 @@ func (s *Store) GetRecentNotifications(customerID string, limit int) ([]Notifica
 	for rows.Next() {
 		var e NotificationLogEntry
 		var createdAt, errorMsg string
-		if err := rows.Scan(&e.EventType, &e.Severity, &e.Message, &e.Status, &errorMsg, &createdAt); err != nil {
+		if err := rows.Scan(&e.EventType, &e.Severity, &e.Message, &e.Status, &errorMsg, &e.Channel, &createdAt); err != nil {
 			return nil, err
 		}
 		e.CreatedAt = parseSQLiteTime(createdAt)
@@ -658,6 +700,177 @@ func (s *Store) UpdateRetrievalPassword(customerID, newPassword string) error {
 	return err
 }
 
+// --- Event system ---
+
+// Event represents a single event record.
+type Event struct {
+	ID          int64
+	CustomerID  string
+	EventType   string
+	Severity    string // "info", "warning", "error"
+	Message     string
+	DetailsJSON string // raw JSON
+	Source      string // "controller" or "hub"
+	CreatedAt   time.Time
+}
+
+// SaveEvent inserts a new event and returns its ID.
+func (s *Store) SaveEvent(customerID, eventType, severity, message, detailsJSON, source string) (int64, error) {
+	if detailsJSON == "" {
+		detailsJSON = "{}"
+	}
+	if source == "" {
+		source = "controller"
+	}
+	res, err := s.db.Exec(`
+		INSERT INTO events (customer_id, event_type, severity, message, details_json, source)
+		VALUES (?, ?, ?, ?, ?, ?)`,
+		customerID, eventType, severity, message, detailsJSON, source,
+	)
+	if err != nil {
+		return 0, err
+	}
+	return res.LastInsertId()
+}
+
+// GetRecentEvents returns the most recent events for a customer, newest first.
+func (s *Store) GetRecentEvents(customerID string, limit int) ([]Event, error) {
+	rows, err := s.db.Query(`
+		SELECT id, customer_id, event_type, severity, message, details_json, source, created_at
+		FROM events
+		WHERE customer_id = ?
+		ORDER BY created_at DESC
+		LIMIT ?`, customerID, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanEvents(rows)
+}
+
+// GetEventsByType returns events of a specific type for a customer since a given time.
+func (s *Store) GetEventsByType(customerID, eventType string, since time.Time) ([]Event, error) {
+	rows, err := s.db.Query(`
+		SELECT id, customer_id, event_type, severity, message, details_json, source, created_at
+		FROM events
+		WHERE customer_id = ? AND event_type = ? AND created_at >= ?
+		ORDER BY created_at DESC`,
+		customerID, eventType, since.UTC().Format("2006-01-02 15:04:05"))
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanEvents(rows)
+}
+
+// GetLatestEventByType returns the most recent event of a given type for a customer.
+func (s *Store) GetLatestEventByType(customerID, eventType string) (*Event, error) {
+	var e Event
+	var createdAt string
+	err := s.db.QueryRow(`
+		SELECT id, customer_id, event_type, severity, message, details_json, source, created_at
+		FROM events
+		WHERE customer_id = ? AND event_type = ?
+		ORDER BY created_at DESC
+		LIMIT 1`, customerID, eventType,
+	).Scan(&e.ID, &e.CustomerID, &e.EventType, &e.Severity, &e.Message, &e.DetailsJSON, &e.Source, &createdAt)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	e.CreatedAt = parseSQLiteTime(createdAt)
+	return &e, nil
+}
+
+// GetAllRecentEvents returns the most recent events across all customers.
+func (s *Store) GetAllRecentEvents(limit int) ([]Event, error) {
+	rows, err := s.db.Query(`
+		SELECT id, customer_id, event_type, severity, message, details_json, source, created_at
+		FROM events
+		ORDER BY created_at DESC
+		LIMIT ?`, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanEvents(rows)
+}
+
+// CountEventsBySeverity returns a count of events per severity for a customer since a given time.
+func (s *Store) CountEventsBySeverity(customerID string, since time.Time) (map[string]int, error) {
+	rows, err := s.db.Query(`
+		SELECT severity, COUNT(*) FROM events
+		WHERE customer_id = ? AND created_at >= ?
+		GROUP BY severity`,
+		customerID, since.UTC().Format("2006-01-02 15:04:05"))
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	counts := make(map[string]int)
+	for rows.Next() {
+		var sev string
+		var count int
+		if err := rows.Scan(&sev, &count); err != nil {
+			return nil, err
+		}
+		counts[sev] = count
+	}
+	return counts, rows.Err()
+}
+
+// PruneEvents deletes events older than the given number of days.
+func (s *Store) PruneEvents(maxDays int) (int64, error) {
+	cutoff := time.Now().AddDate(0, 0, -maxDays).UTC().Format("2006-01-02 15:04:05")
+	res, err := s.db.Exec("DELETE FROM events WHERE created_at < ?", cutoff)
+	if err != nil {
+		return 0, err
+	}
+	return res.RowsAffected()
+}
+
+// GetActiveCustomerIDs returns customer IDs from customer_configs where status is 'active'.
+func (s *Store) GetActiveCustomerIDs() ([]string, error) {
+	rows, err := s.db.Query("SELECT customer_id FROM customer_configs WHERE status = 'active'")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var ids []string
+	for rows.Next() {
+		var id string
+		if err := rows.Scan(&id); err != nil {
+			return nil, err
+		}
+		ids = append(ids, id)
+	}
+	return ids, rows.Err()
+}
+
+// Ping verifies the database is accessible.
+func (s *Store) Ping() error {
+	var n int
+	return s.db.QueryRow("SELECT 1").Scan(&n)
+}
+
+func scanEvents(rows *sql.Rows) ([]Event, error) {
+	var events []Event
+	for rows.Next() {
+		var e Event
+		var createdAt string
+		if err := rows.Scan(&e.ID, &e.CustomerID, &e.EventType, &e.Severity, &e.Message, &e.DetailsJSON, &e.Source, &createdAt); err != nil {
+			return nil, err
+		}
+		e.CreatedAt = parseSQLiteTime(createdAt)
+		events = append(events, e)
+	}
+	return events, rows.Err()
+}
+
 // parseSQLiteTime tries multiple formats that modernc.org/sqlite may return.
 func parseSQLiteTime(s string) time.Time {
 	formats := []string{

hub/internal/web/configs.go

@@ -223,12 +223,14 @@ func (s *Server) handleCustomerUnified(w http.ResponseWriter, r *http.Request, c
 		}
 	}
 
-	// History, notifications, infra backup
+	// History, notifications, events, infra backup
 	var history []store.CustomerSummary
 	var notifPrefs *store.NotificationPrefs
 	var recentNotifs []store.NotificationLogEntry
 	var infraMeta *store.InfraBackupMeta
 	var infraBackupAge string
+	var events []store.Event
+	var eventCounts map[string]int
 
 	if customer != nil {
 		history, _ = s.store.GetCustomerHistory(customerID, 24*time.Hour)
@@ -238,6 +240,8 @@ func (s *Server) handleCustomerUnified(w http.ResponseWriter, r *http.Request, c
 		if infraMeta != nil {
 			infraBackupAge = timeAgo(infraMeta.UpdatedAt)
 		}
+		events, _ = s.store.GetRecentEvents(customerID, 50)
+		eventCounts, _ = s.store.CountEventsBySeverity(customerID, time.Now().Add(-24*time.Hour))
 	}
 
 	type pageData struct {
@@ -270,6 +274,9 @@ func (s *Server) handleCustomerUnified(w http.ResponseWriter, r *http.Request, c
 		RecentNotifications []store.NotificationLogEntry
 		History             []store.CustomerSummary
 
+		Events      []store.Event
+		EventCounts map[string]int // severity → count (last 24h)
+
 		Flash     string
 		ActiveNav string
 	}
@@ -304,6 +311,9 @@ func (s *Server) handleCustomerUnified(w http.ResponseWriter, r *http.Request, c
 		RecentNotifications: recentNotifs,
 		History:             history,
 
+		Events:      events,
+		EventCounts: eventCounts,
+
 		Flash:     r.URL.Query().Get("flash"),
 		ActiveNav: "configs",
 	}
@@ -697,7 +707,7 @@ func buildConfigJSON(r *http.Request) string {
 		overrides["git"] = git
 	}
 
-	// Monitoring UUIDs
+	// Monitoring UUIDs (legacy — only written if user explicitly provides values)
 	uuids := make(map[string]interface{})
 	for _, key := range []string{"heartbeat", "system_health", "db_dump", "backup", "backup_integrity"} {
 		if v := strings.TrimSpace(r.FormValue("uuid_" + key)); v != "" {

hub/internal/web/controller.yaml.default

@@ -80,12 +80,12 @@ backup:
 monitoring:
   enabled: true
   healthchecks_base: "https://status.felhom.eu"
-  ping_uuids:
-    heartbeat: ""                                  # Every 5 min — controller process alive
-    system_health: ""                              # Every 5 min — comprehensive system check
-    db_dump: ""                                    # Daily — after database dumps
-    backup: ""                                     # Daily — after restic snapshot
-    backup_integrity: ""                           # Weekly (Sunday) — restic check
+  # ping_uuids: (deprecated — monitoring is now handled by the Hub event system)
+  #   heartbeat: ""
+  #   system_health: ""
+  #   db_dump: ""
+  #   backup: ""
+  #   backup_integrity: ""
   system_health_interval: "5m"
   health_check_schedule: "06:00"
   thresholds:

hub/internal/web/server.go

@@ -40,6 +40,13 @@ func New(store *store.Store, passwordHash, apiKey string, staleThreshold time.Du
 			b, _ := json.Marshal(v)
 			return template.JS(b)
 		},
+		"add": func(a, b int) int { return a + b },
+		"mapGet": func(m map[string]int, key string) int {
+			if m == nil {
+				return 0
+			}
+			return m[key]
+		},
 	}
 
 	tmpl := template.Must(template.New("").Funcs(funcMap).ParseFS(templateFS, "templates/*.html"))
@@ -232,6 +239,8 @@ func (s *Server) handleDashboard(w http.ResponseWriter, r *http.Request) {
 		store.CustomerSummary
 		OverallStatus string // "ok", "warn", "down", "pending"
 		BackupAge     string
+		EventErrors   int
+		EventWarnings int
 	}
 
 	// Build map of report customers keyed by ID
@@ -266,6 +275,12 @@ func (s *Server) handleDashboard(w http.ResponseWriter, r *http.Request) {
 			dc.BackupAge = "–"
 		}
 
+		// Event counts (last 24h)
+		if counts, err := s.store.CountEventsBySeverity(c.CustomerID, time.Now().Add(-24*time.Hour)); err == nil {
+			dc.EventErrors = counts["error"]
+			dc.EventWarnings = counts["warning"]
+		}
+
 		data = append(data, dc)
 	}
 

hub/internal/web/templates/config_form.html

@@ -96,8 +96,9 @@
                 </div>
             </details>
 
-            <details class="card" {{if index .Overrides "monitoring"}}open{{end}}>
-                <summary><h2 style="display:inline">Monitoring UUIDs</h2></summary>
+            <details class="card">
+                <summary><h2 style="display:inline">Monitoring UUIDs</h2> <span class="severity-badge severity-warning" style="font-size: 0.7em; vertical-align: middle;">Legacy</span></summary>
+                <p class="text-muted" style="margin: 0.5rem 0;">Healthchecks ping UUIDs are deprecated. Monitoring is now handled natively by the Hub event system. These fields are kept for backward compatibility with older controllers.</p>
                 <div class="form-grid" style="margin-top: 1rem;">
                     {{$uuids := ""}}
                     {{with .Overrides}}{{with index . "monitoring"}}{{with index . "ping_uuids"}}{{$uuids = .}}{{end}}{{end}}{{end}}

hub/internal/web/templates/customer_unified.html

@@ -403,6 +403,61 @@
             {{end}}
         </section>
 
+        <!-- Events -->
+        <section class="card">
+            <h2>Events
+                {{if .EventCounts}}
+                    {{with mapGet .EventCounts "error"}}<span class="severity-badge severity-error">{{.}} error{{if gt . 1}}s{{end}}</span>{{end}}
+                    {{with mapGet .EventCounts "warning"}}<span class="severity-badge severity-warning">{{.}} warning{{if gt . 1}}s{{end}}</span>{{end}}
+                {{end}}
+                <span class="text-muted" style="font-size: 0.7em; font-weight: normal;"> (last 24h)</span>
+            </h2>
+            {{if .Events}}
+            <div style="margin-bottom: 0.5rem;">
+                <button class="btn btn-sm btn-outline event-filter active" data-filter="all">All</button>
+                <button class="btn btn-sm btn-outline event-filter" data-filter="error">Errors</button>
+                <button class="btn btn-sm btn-outline event-filter" data-filter="warning">Warnings</button>
+                <button class="btn btn-sm btn-outline event-filter" data-filter="info">Info</button>
+            </div>
+            <table class="history-table" id="events-table">
+                <thead>
+                    <tr>
+                        <th>Time</th>
+                        <th>Severity</th>
+                        <th>Type</th>
+                        <th>Message</th>
+                        <th>Source</th>
+                    </tr>
+                </thead>
+                <tbody>
+                    {{range .Events}}
+                    <tr data-severity="{{.Severity}}">
+                        <td title="{{.CreatedAt.Format "2006-01-02 15:04:05"}}">{{.CreatedAt.Format "Jan 02 15:04"}}</td>
+                        <td><span class="severity-badge severity-{{.Severity}}">{{.Severity}}</span></td>
+                        <td><code>{{.EventType}}</code></td>
+                        <td>{{.Message}}</td>
+                        <td>{{.Source}}</td>
+                    </tr>
+                    {{end}}
+                </tbody>
+            </table>
+            <script>
+            document.querySelectorAll('.event-filter').forEach(btn => {
+                btn.addEventListener('click', function() {
+                    document.querySelectorAll('.event-filter').forEach(b => b.classList.remove('active'));
+                    this.classList.add('active');
+                    const filter = this.dataset.filter;
+                    document.querySelectorAll('#events-table tbody tr').forEach(row => {
+                        row.style.display = (filter === 'all' || row.dataset.severity === filter) ? '' : 'none';
+                    });
+                });
+            });
+            </script>
+            {{else}}
+            <p class="text-muted">No events recorded yet.</p>
+            {{end}}
+        </section>
+
         <!-- Notifications -->
         <section class="card">
             <h2>Notifications</h2>
@@ -424,6 +479,7 @@
                 <thead>
                     <tr>
                         <th>Time</th>
+                        <th>Channel</th>
                         <th>Event</th>
                         <th>Status</th>
                         <th>Message</th>
@@ -433,6 +489,7 @@
                     {{range .RecentNotifications}}
                     <tr>
                         <td>{{.CreatedAt.Format "Jan 02 15:04"}}</td>
+                        <td><span class="status-badge status-badge-{{.Channel}}">{{.Channel}}</span></td>
                         <td>{{.EventType}}</td>
                         <td><span class="status-badge status-badge-{{.Status}}">{{.Status}}</span></td>
                         <td>{{.Message}}</td>

hub/internal/web/templates/dashboard.html

@@ -28,6 +28,7 @@
                 <tr>
                     <th>Customer</th>
                     <th>Status</th>
+                    <th>Events</th>
                     <th>Last Seen</th>
                     <th>CPU</th>
                     <th>Memory</th>
@@ -49,6 +50,7 @@
                             {{if eq .OverallStatus "ok"}}OK{{else if eq .OverallStatus "warn"}}WARN{{else if eq .OverallStatus "disabled"}}PAUSED{{else if eq .OverallStatus "pending"}}PENDING{{else}}DOWN{{end}}
                         </span>
                     </td>
+                    <td>{{if eq .OverallStatus "pending"}}—{{else}}{{if gt (add .EventErrors .EventWarnings) 0}}{{if gt .EventErrors 0}}<span class="severity-badge severity-error">{{.EventErrors}}</span>{{end}}{{if gt .EventWarnings 0}}<span class="severity-badge severity-warning">{{.EventWarnings}}</span>{{end}}{{else}}<span class="text-muted">—</span>{{end}}{{end}}</td>
                     <td>{{if eq .OverallStatus "pending"}}—{{else}}{{timeAgo .ReceivedAt}}{{end}}</td>
                     <td>{{if eq .OverallStatus "pending"}}—{{else}}{{formatFloat .CPUPercent}}%{{end}}</td>
                     <td>{{if eq .OverallStatus "pending"}}—{{else}}{{formatFloat .MemoryPercent}}%{{end}}</td>

hub/internal/web/templates/style.css

@@ -564,6 +564,55 @@ code {
     color: var(--text-muted);
 }
 
+/* Severity badges */
+.severity-badge {
+    display: inline-block;
+    padding: 0.15em 0.5em;
+    border-radius: 4px;
+    font-size: 0.8em;
+    font-weight: 600;
+    line-height: 1.4;
+}
+
+.severity-error {
+    background: rgba(239, 68, 68, 0.15);
+    color: #ef4444;
+}
+
+.severity-warning {
+    background: rgba(245, 158, 11, 0.15);
+    color: #f59e0b;
+}
+
+.severity-info {
+    background: rgba(59, 130, 246, 0.15);
+    color: #3b82f6;
+}
+
+/* Event filter buttons */
+.event-filter {
+    font-size: 0.8em;
+    padding: 0.2em 0.6em;
+    cursor: pointer;
+}
+
+.event-filter.active {
+    background: var(--accent);
+    color: #fff;
+    border-color: var(--accent);
+}
+
+/* Notification channel badges */
+.status-badge-operator {
+    background: rgba(139, 92, 246, 0.15);
+    color: #8b5cf6;
+}
+
+.status-badge-customer {
+    background: rgba(59, 130, 246, 0.15);
+    color: #3b82f6;
+}
+
 /* Responsive */
 @media (max-width: 768px) {
     .container { padding: 1rem; }