diff --git a/pom.xml b/pom.xml
index 840afc1..05b1f4c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -97,7 +97,7 @@
                         <arg>--gc=G1</arg>
                         <arg>--enable-url-protocols=https</arg>
                         <arg>-H:IncludeResources="simplelogger.properties"</arg>
-                        <arg>--initialize-at-build-time=org.slf4j.simple.SimpleLogger,org.slf4j.simple.SimpleLoggerFactory</arg>
+                        <arg>--initialize-at-build-time=org.slf4j.simple.SimpleLogger,org.slf4j.simple.SimpleLoggerFactory,org.slf4j.simple.SimpleLoggerConfiguration</arg>
                         <arg>-H:ReflectionConfigurationFiles=src/main/resources/reflect-config.json</arg>
                     </buildArgs>
                     <metadataRepository>
diff --git a/src/main/java/lion/CustomUtil.java b/src/main/java/lion/CustomUtil.java
index 6621e72..3c7ca07 100644
--- a/src/main/java/lion/CustomUtil.java
+++ b/src/main/java/lion/CustomUtil.java
@@ -3,6 +3,8 @@ package lion;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import lombok.Data;
 
+import java.io.IOException;
+import java.net.ServerSocket;
 import java.util.concurrent.atomic.AtomicInteger;
 
 
@@ -12,4 +14,15 @@ public class CustomUtil {
     public static AtomicInteger counter = new AtomicInteger();
 
     public static ObjectMapper objectMapper = new ObjectMapper();
+
+    public static int _findIdlePort(int port) {
+        for(int i=port; i<65535; i++){
+            try(ServerSocket ignored = new ServerSocket(i)){
+                ignored.close();
+                return  i;
+            }catch (IOException ignored) {
+            }
+        }
+        return -1;
+    }
 }
diff --git a/src/main/java/lion/storageNode.java b/src/main/java/lion/storageNode.java
index 77f0efd..db521d1 100644
--- a/src/main/java/lion/storageNode.java
+++ b/src/main/java/lion/storageNode.java
@@ -54,6 +54,8 @@ public class storageNode {
         counter = 0;
         promises = new HashMap<>();
 
+        int real_port = CustomUtil._findIdlePort(26321);
+
         channelFuture = new ServerBootstrap()
                 .channel(NioServerSocketChannel.class)
                 .group(new NioEventLoopGroup())
@@ -64,12 +66,25 @@ public class storageNode {
                         channel.pipeline().addLast(new MessageCodec());
                         channel.pipeline().addLast(new MyChannelInboundHandlerAdapter(tempQueue));
                     }
-                })
-                .bind(26321);
+                }).bind(real_port);
+        log.info("listening on port {}", real_port);
 
-        try(Socket socket = new Socket()){
-            socket.connect(new InetSocketAddress("lionwebsite.xyz", 26322));
-        } catch (Exception ignored) {}
+        int i;
+        for(i=0; i<=20; i++) {
+            try (Socket socket = new Socket()) {
+                socket.setSoTimeout(3000);
+                log.info("wake up main server on port {}", 26322 + i);
+                socket.connect(new InetSocketAddress("lionwebsite.xyz", 26322 + i));
+                byte[] bytes = socket.getInputStream().readAllBytes();
+                if(bytes.length > 0 && new String(bytes).equals("lionwebsite")) {
+                    break;
+                }
+            } catch (Exception ignored) {
+            }
+        }
+        if (i==20) {
+            log.info("server connect failed");
+        }
         downloadCheckService = new DownloadCheckService(queue, promises);
         checkThreadPool = Executors.newScheduledThreadPool(1);
         checkThreadPool.scheduleAtFixedRate(this::mainThread, 5, 5, TimeUnit.SECONDS);