diff --git a/perl-xCAT/xCAT/Schema.pm b/perl-xCAT/xCAT/Schema.pm
index 15cc1bbb0..87fb9ad03 100644
--- a/perl-xCAT/xCAT/Schema.pm
+++ b/perl-xCAT/xCAT/Schema.pm
@@ -1277,7 +1277,9 @@ nics => {
                         If only one ip address is associated with each NIC:
                             <nic1>!<ext1>,<nic2>!<ext2>,..., for example, eth0!-eth0,ib0!-ib0
                         If multiple ip addresses are associcated with each NIC:
-                            <nic1>!<ext1>|<ext2>,<nic2>!<ext1>|<ext2>,..., for example,  eth0!-eth0|-eth0-ipv6,ib0!-ib0|-ib0-ipv6. The xCAT object definition commands support to use nichostnamesuffixes.<nicname> as the sub attributes.',
+                            <nic1>!<ext1>|<ext2>,<nic2>!<ext1>|<ext2>,..., for example,  eth0!-eth0|-eth0-ipv6,ib0!-ib0|-ib0-ipv6. 
+                        The xCAT object definition commands support to use nichostnamesuffixes.<nicname> as the sub attributes. 
+                        Note:  According to DNS rules a hostname must be a text string up to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus sign (-),and period (.). When you are specifying "nichostnamesuffixes" or "nicaliases" make sure the resulting hostnames will conform to this naming convention',
             nictypes => 'Comma-separated list of NIC types per NIC. <nic1>!<type1>,<nic2>!<type2>, e.g. eth0!Ethernet,ib0!Infiniband. The xCAT object definition commands support to use nictypes.<nicname> as the sub attributes.', 
             niccustomscripts => 'Comma-separated list of custom scripts per NIC.  <nic1>!<script1>,<nic2>!<script2>, e.g. eth0!configeth eth0, ib0!configib ib0. The xCAT object definition commands support to use niccustomscripts.<nicname> as the sub attribute
 .',
@@ -1286,7 +1288,7 @@ nics => {
                     <nic1>!<network1>,<nic2>!<network2>, for example, eth0!10_0_0_0-255_255_0_0, ib0!11_0_0_0-255_255_0_0
                 If multiple ip addresses are associated with each NIC:
                     <nic1>!<network1>|<network2>,<nic2>!<network1>|<network2>, for example, eth0!10_0_0_0-255_255_0_0|fd55:faaf:e1ab:336::/64,ib0!11_0_0_0-255_255_0_0|2001:db8:1:0::/64. The xCAT object definition commands support to use nicnetworks.<nicname> as the sub attributes.',
-            nicaliases => 'Comma-separated list of aliases for each NIC.
+            nicaliases => 'Comma-separated list of hostname aliases for each NIC.
             Format: eth0!<alias list>,eth1!<alias1 list>|<alias2 list>
 			For multiple aliases per nic use a space-separated list.
             For example: eth0!moe larry curly,eth1!tom|jerry',