diff --git a/tests/integration/multi-instance/multi_instance_test.go b/tests/integration/multi-instance/multi_instance_test.go
index 800d1ced..1a4ede06 100644
--- a/tests/integration/multi-instance/multi_instance_test.go
+++ b/tests/integration/multi-instance/multi_instance_test.go
@@ -495,7 +495,14 @@ func (e *env) loginAlice(t *testing.T) *userClient {
 // alice 的方式 redeem 并设 rootPass。
 func (e *env) grantAliceProjectCreate(t *testing.T, rootCred string) {
 	t.Helper()
-	rootSecret := activationSecret(t, rootCred)
+	raw, err := os.ReadFile(rootCred)
+	if err != nil {
+		t.Fatal(err)
+	}
+	rootSecret := strings.TrimSpace(string(raw))
+	if rootSecret == "" {
+		t.Fatal("bootstrap-admin credential file is empty")
+	}
 	jar, err := cookiejar.New(nil)
 	if err != nil {
 		t.Fatal(err)