The floating address is read each time the summary is asked

server add records it after restarting the new control plane, which then
never named it.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

internal/cli/controlplanes.go

@@ -25,8 +25,9 @@ const floatingPath = "/etc/llmgw/floating"
 // held it last and says nothing about a standby that has stopped — and a
 // standby that is not there is the thing worth seeing before it is needed.
 type controlPlaneProbe struct {
-	st       *store.DB
-	self     string
+	st   *store.DB
+	self string
+	// floating is the file the floating address is recorded in.
 	floating string
 	client   *http.Client
 	// leaderURL is where a host is asked; tests point it elsewhere.
@@ -65,7 +66,9 @@ func (p *controlPlaneProbe) Status() adminapi.ControlPlanes {
 		p.at, p.last = time.Now(), adminapi.ControlPlanes{}
 		return p.last
 	}
-	out := adminapi.ControlPlanes{Members: make([]adminapi.ControlPlane, len(cps)), Floating: p.floating}
+	// Read each time: server add writes it after this process may have
+	// started.
+	out := adminapi.ControlPlanes{Members: make([]adminapi.ControlPlane, len(cps)), Floating: floatingAddress(p.floating)}
 	var wg sync.WaitGroup
 	for i, cp := range cps {
 		host := cp.URL
@@ -75,8 +78,8 @@ func (p *controlPlaneProbe) Status() adminapi.ControlPlanes {
 		out.Members[i] = adminapi.ControlPlane{Name: cp.Name, Address: host, This: cp.Name == p.self}
 		wg.Go(func() { out.Members[i].State = p.ask(ctx, host) })
 	}
-	if p.floating != "" {
-		wg.Go(func() { out.FloatingUp = p.ask(ctx, p.floating) == "leading" })
+	if out.Floating != "" {
+		wg.Go(func() { out.FloatingUp = p.ask(ctx, out.Floating) == "leading" })
 	}
 	wg.Wait()
 	p.at, p.last = time.Now(), out

internal/cli/controlplanes_test.go

@@ -76,7 +76,11 @@ func TestTheProbeAsksEachControlPlaneWhetherItLeads(t *testing.T) {
 	}
 	at := map[string]string{"10.0.0.1": leading.URL, "10.0.0.2": standby.URL, "10.0.0.3": gone.URL, "10.0.0.161": leading.URL}
 	p := newControlPlaneProbe(st, ":8080")
-	p.self, p.floating = "two", "10.0.0.161"
+	floating := filepath.Join(t.TempDir(), "floating")
+	if err := os.WriteFile(floating, []byte("10.0.0.161/24\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	p.self, p.floating = "two", floating
 	p.leaderURL = func(host string) string { return at[host] + "/leader" }
 
 	s := p.Status()