diff --git a/JWT/deploy/backup.sh b/JWT/deploy/backup.sh
index 22cf7c1..634aa3c 100755
--- a/JWT/deploy/backup.sh
+++ b/JWT/deploy/backup.sh
@@ -1,3 +1,10 @@
 #!/bin/bash
 
-sudo mv server.jar server.bak.jar
+if [ -f server.jar ]; then
+  sudo mv server.jar server.bak.jar
+  echo "server.bak.jar create."
+  exit 0
+fi
+
+echo "no server.jar file found."
+exit 0