diff --git a/src/main/java/lion/Message/AbstractMessage.java b/src/main/java/lion/Message/AbstractMessage.java
index ff7aada..8a2633a 100644
--- a/src/main/java/lion/Message/AbstractMessage.java
+++ b/src/main/java/lion/Message/AbstractMessage.java
@@ -14,6 +14,8 @@ public class AbstractMessage {
 
     public static final byte MAINTAIN_MESSAGE = 7;
 
+    public static final byte AVAILABLE_CHECK_MESSAGE = 8;
+
     public byte messageType;
 
     public int messageId;
diff --git a/src/main/java/lion/Message/Main/AvailableCheckMessage.java b/src/main/java/lion/Message/Main/AvailableCheckMessage.java
new file mode 100644
index 0000000..60d7ada
--- /dev/null
+++ b/src/main/java/lion/Message/Main/AvailableCheckMessage.java
@@ -0,0 +1,11 @@
+package lion.Message.Main;
+
+import lion.Message.AbstractMessage;
+import lombok.Data;
+
+@Data
+public class AvailableCheckMessage extends AbstractMessage {
+    {
+        messageType = AVAILABLE_CHECK_MESSAGE;
+    }
+}
diff --git a/src/main/java/lion/Message/MessageCodec.java b/src/main/java/lion/Message/MessageCodec.java
index d61c135..7106a95 100644
--- a/src/main/java/lion/Message/MessageCodec.java
+++ b/src/main/java/lion/Message/MessageCodec.java
@@ -45,6 +45,7 @@ public class MessageCodec extends ByteToMessageCodec<AbstractMessage> {
             case AbstractMessage.DELETE_GALLERY_MESSAGE -> objectMapper.readValue(metadata, DeleteGalleryMessage.class);
             case AbstractMessage.IDENTITY_MESSAGE -> objectMapper.readValue(metadata, IdentityMessage.class);
             case AbstractMessage.MAINTAIN_MESSAGE -> objectMapper.readValue(metadata, MaintainMessage.class);
+            case AbstractMessage.AVAILABLE_CHECK_MESSAGE -> objectMapper.readValue(metadata, AvailableCheckMessage.class);
             default -> null;
         };
 
diff --git a/src/main/java/lion/storageNode.java b/src/main/java/lion/storageNode.java
index 3719c80..e051f56 100644
--- a/src/main/java/lion/storageNode.java
+++ b/src/main/java/lion/storageNode.java
@@ -177,6 +177,11 @@ public class storageNode {
                     ResponseMessage responseMessage = new ResponseMessage(deleteGalleryMessage.messageId, result);
                     ctx.writeAndFlush(responseMessage);
                 }
+                case AbstractMessage.AVAILABLE_CHECK_MESSAGE -> {
+                    AvailableCheckMessage acm = (AvailableCheckMessage) abstractMessage;
+                    ResponseMessage responseMessage = new ResponseMessage(acm.messageId, (byte)0);
+                    ctx.writeAndFlush(responseMessage);
+                }
             }
 //
 //            //修复预览