diff --git a/plugins/mongodb/index.py b/plugins/mongodb/index.py
index 0be3bacb4..6a54f7b1a 100755
--- a/plugins/mongodb/index.py
+++ b/plugins/mongodb/index.py
@@ -1535,8 +1535,8 @@ def installPreInspection(version):
     if mw.isAppleSystem():
         return 'ok'
 
-    sys = mw.execShell(
-        "cat /etc/*-release | grep PRETTY_NAME |awk -F = '{print $2}' | awk -F '\"' '{print $2}'| awk '{print $1}'")
+    cmd = "cat /etc/*-release | grep PRETTY_NAME |awk -F = '{print $2}' | awk -F '\"' '{print $2}'| awk '{print $1}'"
+    sys = mw.execShell(cmd)
 
     if sys[1] != '':
         return '暂时不支持该系统'