diff --git a/cmd/mesh-host/backup_event_test.go b/cmd/mesh-host/backup_event_test.go
index 0a773cc..5871dc1 100644
--- a/cmd/mesh-host/backup_event_test.go
+++ b/cmd/mesh-host/backup_event_test.go
@@ -3,9 +3,13 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"errors"
+	"fmt"
 	"strings"
 	"testing"
 	"time"
+
+	"github.com/novox/mesh-host/internal/link"
 )
 
 func backupEvent(node, module string, ok bool, at time.Time, why string) []byte {
@@ -39,4 +43,34 @@ func TestABackupEndsWhenItsEventSaysSo(t *testing.T) {
 	if done, words := run(50 * time.Millisecond); done || !strings.Contains(words, "did not say it was done") {
 		t.Errorf("silence within the bound: done=%v words=%q", done, words)
 	}
+
+	// The ask that starts it (sweep 2026-10-30): one that never reached the holder (nothing on this machine answers it
+	// while the tool runner restarts) is asked again within its bound, and past it fails saying so; one that may have
+	// reached it is never asked twice.
+	notAsked := fmt.Errorf("node-backup.now could not be asked: %w: nothing on this machine answers "+
+		"mesh.seat.node-backup.tool.now.ace", link.ErrNotAsked)
+	for _, row := range []struct {
+		name    string
+		answers []error
+		within  time.Duration
+		asked   int
+		words   string
+	}{
+		{"heard after the tool runner is back", []error{notAsked, notAsked, nil}, time.Second, 3, ""},
+		// Asked again until the bound, however slow the machine: at least twice, and fewer than it would answer.
+		{"never heard within the bound", []error{notAsked, notAsked, notAsked, notAsked, notAsked, nil}, 25 * time.Millisecond,
+			0, "times over"},
+		{"a timeout may have started it", []error{errors.New("no answer from x: context deadline exceeded"), nil},
+			time.Second, 1, "deadline exceeded"},
+		{"a refusal in words", []error{errors.New("restic is not on this machine"), nil}, time.Second, 1, "not on this"},
+	} {
+		asked := 0
+		_, err := askUntilHeard(context.Background(), func(context.Context) (json.RawMessage, error) {
+			asked++
+			return json.RawMessage(`{}`), row.answers[asked-1]
+		}, row.within, func(int) time.Duration { return 10 * time.Millisecond })
+		if row.asked == 0 && (asked < 2 || asked >= len(row.answers)) || row.asked != 0 && asked != row.asked || (row.words == "") != (err == nil) || err != nil && !strings.Contains(err.Error(), row.words) {
+			t.Errorf("%s: asked %d times, %v", row.name, asked, err)
+		}
+	}
 }
diff --git a/cmd/mesh-host/nodeagent.go b/cmd/mesh-host/nodeagent.go
index a67f6a0..7d3ba5f 100644
--- a/cmd/mesh-host/nodeagent.go
+++ b/cmd/mesh-host/nodeagent.go
@@ -165,19 +165,54 @@ func backupNode(session *link.Session) func(ctx context.Context, module string)
 		defer stop()
 		// A module this machine backs nothing of up moves without a backup: never held for one that cannot run (issue
 		// 1945). An answer that cannot be had or read asks for the backup as before.
-		if said, err := session.AskSeat(ctx, "node-backup", "backed-up", map[string]any{"module": module}, 30*time.Second); err == nil {
+		ask := func(verb string) func(context.Context) (json.RawMessage, error) {
+			return func(ctx context.Context) (json.RawMessage, error) {
+				return session.AskSeat(ctx, "node-backup", verb, map[string]any{"module": module}, 30*time.Second)
+			}
+		}
+		if said, err := askUntilHeard(ctx, ask("backed-up"), backupAskFor, link.Backoff); err == nil {
 			if nothing, read := declaresNothingToBackUp(said, module); read && nothing {
 				return agent.Backup{Done: true, Words: module + " declares nothing to back up on this machine"}
 			}
 		}
 		asked := time.Now()
-		if _, err := session.AskSeat(ctx, "node-backup", "now", map[string]any{"module": module}, 30*time.Second); err != nil {
+		if _, err := askUntilHeard(ctx, ask("now"), backupAskFor, link.Backoff); err != nil {
 			return agent.Backup{Words: err.Error()}
 		}
 		return awaitBackup(ctx, events, session.Membership.Node, module, asked, backupWithin)
 	}
 }
 
+// backupAskFor is how long the backup's ask is asked again while it is known never to have reached the holder of
+// node-backup: nothing on this machine answers it (the tool runner restarting, its subscriptions not made yet) or no
+// link is open. The sweep of 2026-10-30 met it on ace's redis, postgres and restic (14:03), step-ca (13:55) and
+// mesh-vault on novox (15:22): each was held on one unanswered ask. Past the bound the backup failed, said with how
+// often and how long it was asked: the module is held, its have says so, and the assigner asks the operator.
+var backupAskFor = 3 * time.Minute
+
+// askUntilHeard asks, and asks again after wait(try) while the answer says the ask was never delivered (link.ErrNotAsked),
+// for at most within: an ask that may have reached its holder (a timeout, a refusal in words) is never asked twice, so a
+// backup is never started twice.
+func askUntilHeard(ctx context.Context, ask func(context.Context) (json.RawMessage, error), within time.Duration,
+	wait func(int) time.Duration) (json.RawMessage, error) {
+	began := time.Now()
+	for try := 1; ; try++ {
+		said, err := ask(ctx)
+		if err == nil || !errors.Is(err, link.ErrNotAsked) {
+			return said, err
+		}
+		pause := wait(try)
+		if time.Since(began)+pause > within {
+			return nil, fmt.Errorf("asked %d times over %s and never heard: %w", try, time.Since(began).Round(time.Second), err)
+		}
+		select {
+		case <-ctx.Done():
+			return nil, fmt.Errorf("the node agent was stopped while it asked again: %w", err)
+		case <-time.After(pause):
+		}
+	}
+}
+
 // awaitBackup waits for the event that says the backup of a module on this node ended, within the bound: done when it
 // says ok, held on its words when it does not, and held when it says nothing within the bound. An event of another node
 // or module, or from before the ask, is not the answer.