diff --git a/xCAT-client/pods/man1/mkzone.1.pod b/xCAT-client/pods/man1/mkzone.1.pod
index f59c74f6d..3f15a50a3 100644
--- a/xCAT-client/pods/man1/mkzone.1.pod
+++ b/xCAT-client/pods/man1/mkzone.1.pod
@@ -13,8 +13,8 @@ B<mkzone> [B<-h> | B<-v>]
 
 The B<mkzone> command is designed to divide the xCAT cluster into multiple zones. The nodes in each zone will share common root ssh keys. This allows the nodes in a zone to be able to as root ssh to each other without password, but cannot do the same to any node in another zone. All zones share a common xCAT Management Node and database including the site table, which defines the attributes of the entire cluster.
 The mkzone command is only supported on Linux ( No AIX support).
-The nodes are not updated with the new root ssh keys by mkzone.  You must run updatenode -k  or xdsh -K to the nodes to update the root ssh keys to the new generated zone keys.    
-
+The nodes are not updated with the new root ssh keys by mkzone.  You must run updatenode -k  or xdsh -K to the nodes to update the root ssh keys to the new generated zone keys. This will also sync any service nodes with the zone keys, if you have a hierarchical cluster.   
+Note: if any zones in the zone table, there must be one and only one defaultzone. Otherwise, errors will occur.
 
 =head1 B<OPTIONS>
 
@@ -39,6 +39,7 @@ if --defaultzone is input, then it will set the zone defaultzone attribute to ye
 if --defaultzone is input and another zone is currently the default,
 then the -f flag must be used to force a change to the new defaultzone.
 If -f flag is not use an error will be returned and no change made. 
+Note: if any zones in the zone table, there must be one and only one defaultzone. Otherwise, errors will occur.
 
 =item B<-a | --addnoderange> I<noderange>