diff --git a/xCAT-server-2.0/usr/lib/xcat/monitoring/xcatmon.pm b/xCAT-server-2.0/usr/lib/xcat/monitoring/xcatmon.pm
index 8bba5555f..8e7390d1a 100644
--- a/xCAT-server-2.0/usr/lib/xcat/monitoring/xcatmon.pm
+++ b/xCAT-server-2.0/usr/lib/xcat/monitoring/xcatmon.pm
@@ -8,16 +8,14 @@ package xCAT_monitoring::xcatmon;
 use xCAT::GlobalDef;
 use xCAT::Utils;
 
-#caches the current node status. (serve1=>{active=>[node1,node3...], unreachable=>[node2, node4..]},....)
-
-$flag;
 
 1;
 #-------------------------------------------------------------------------------
 =head1  xCAT_monitoring:xcatmon  
 =head2    Package Description
    This is a xCAT monitoring plugin. The only thing that this plug-in does is 
-   the node monitoring. 
+   the node monitoring. To activate it simply do the following command:
+      chtab pname=xCAT monitoring.nodestatmon=Y
 =cut
 #-------------------------------------------------------------------------------
 
diff --git a/xCAT-server-2.0/usr/sbin/xcatnodemon b/xCAT-server-2.0/usr/sbin/xcatnodemon
index ae4c442c2..8cba57a5e 100755
--- a/xCAT-server-2.0/usr/sbin/xcatnodemon
+++ b/xCAT-server-2.0/usr/sbin/xcatnodemon
@@ -7,7 +7,8 @@ use xCAT::GlobalDef;
 require("/usr/lib/xcat/monitoring/monitorctrl.pm");
 #################################################################
 # This script is used as a cron job by the xCAT monitoring plug-in
-# to monitor the node status
+# to monitor the node status. To activate it, simply do
+# chtab pname=xCAT monitoring.nodestatmon=Y
 ################################################################## 
 
 ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst)=localtime(time);