diff --git a/ingester-rpc/src/main/java/io/greptime/rpc/TlsOptions.java b/ingester-rpc/src/main/java/io/greptime/rpc/TlsOptions.java
index 4a27424..954b37f 100644
--- a/ingester-rpc/src/main/java/io/greptime/rpc/TlsOptions.java
+++ b/ingester-rpc/src/main/java/io/greptime/rpc/TlsOptions.java
@@ -26,13 +26,13 @@
  */
 public class TlsOptions implements Copiable<TlsOptions> {
 
-    private Optional<File> clientCertChain;
+    private Optional<File> clientCertChain = Optional.empty();
 
-    private Optional<File> privateKey;
+    private Optional<File> privateKey = Optional.empty();
 
-    private Optional<String> privateKeyPassword;
+    private Optional<String> privateKeyPassword = Optional.empty();
 
-    private Optional<File> rootCerts;
+    private Optional<File> rootCerts = Optional.empty();
 
     @Override
     public TlsOptions copy() {