v0.243.0: FileBrowser generated admin password (R-513); per-tier whole-guest backup truth (R-517); skip absent-storage tiers (R-518); OOM-killed worker visible (R-514)

MinAgent: 0.131.0

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/quiesce/tiers.go

@@ -35,6 +35,43 @@ var ErrTiersUnsupported = errors.New("quiesce: agent does not serve /backup/tier
 type BackupTier struct {
 	Target  string
 	Primary bool
+	// StorageAbsent (R-518, agent >= v0.131.0): the agent POSITIVELY determined the tier's storage
+	// does not exist. Only then is the tier skipped; unknown/legacy stay false (fail toward backing up).
+	StorageAbsent bool
+}
+
+// TierSkipNotifier is the OPTIONAL notifier extension for a tier skipped because its storage does not
+// exist (R-518). Optional so every existing TierNotifier keeps compiling.
+type TierSkipNotifier interface {
+	BackupTierSkipped(tier, message string)
+}
+
+// skipAbsentTiers drops the tiers whose storage the agent reports absent (R-518's cheap half,
+// BIGNIGHT: the apps stayed stopped through a PBS tier whose storage did not exist, then it failed).
+// It logs every skip and notifies ONCE per tier per absence (a scheduled loop re-resolves every poll;
+// the note re-arms when the storage reappears).
+func (l *Loop) skipAbsentTiers(tiers []BackupTier) []BackupTier {
+	out := make([]BackupTier, 0, len(tiers))
+	l.skipMu.Lock()
+	defer l.skipMu.Unlock()
+	if l.skipNoted == nil {
+		l.skipNoted = map[string]bool{}
+	}
+	for _, t := range tiers {
+		if !t.StorageAbsent {
+			delete(l.skipNoted, t.Target)
+			out = append(out, t)
+			continue
+		}
+		l.logger.Printf("[WARN] [quiesce] tier %s skipped: its storage does not exist on the host — no app is stopped for it", tierLabel(t.Target))
+		if !l.skipNoted[t.Target] {
+			l.skipNoted[t.Target] = true
+			if n, ok := l.tierNotify.(TierSkipNotifier); ok && n != nil {
+				n.BackupTierSkipped(t.Target, "Whole-guest backup tier "+t.Target+" skipped: its storage does not exist on the host (never provisioned or removed). No app was stopped for it.")
+			}
+		}
+	}
+	return out
 }
 
 // TieredBackend is the OPTIONAL R-82 extension to Backend. A backend that does not implement it
@@ -120,6 +157,14 @@ func (l *Loop) resolveDueTiers(ctx context.Context) (due []dueTier, degraded boo
 	if terr != nil {
 		return nil, false, terr
 	}
+	if len(tiers) > 0 {
+		if kept := l.skipAbsentTiers(tiers); len(kept) == 0 {
+			l.logger.Printf("[WARN] [quiesce] every advertised tier's storage is absent — nothing to back up this cycle")
+			return nil, false, nil
+		} else {
+			tiers = kept
+		}
+	}
 	if len(tiers) == 0 {
 		// An agent that advertises no tiers cannot be backed up per-tier, but it can still be
 		// backed up untargeted. Fail toward DOING the backup, never toward skipping it.