diff --git a/xCAT-server/lib/xcat/plugins/hosts.pm b/xCAT-server/lib/xcat/plugins/hosts.pm
index 3898f63bc..d04018923 100644
--- a/xCAT-server/lib/xcat/plugins/hosts.pm
+++ b/xCAT-server/lib/xcat/plugins/hosts.pm
@@ -32,7 +32,7 @@ sub addnode {
   my $foundone=0;
   
   while ($idx <= $#hosts) {
-    if ($hosts[$idx] =~ /^${ip}\s/ or $hosts[$idx] =~ /^\d+\.\d+\.\d+\.\d+\s+${node}[\s\.r/) {
+    if ($hosts[$idx] =~ /^${ip}\s/ or $hosts[$idx] =~ /^\d+\.\d+\.\d+\.\d+\s+${node}[\s\.]/) {
       if ($foundone) {
         $hosts[$idx]=""; 
       } else {
diff --git a/xCAT-server/lib/xcat/plugins/tabutils.pm b/xCAT-server/lib/xcat/plugins/tabutils.pm
index 2705996b4..d52e315f1 100644
--- a/xCAT-server/lib/xcat/plugins/tabutils.pm
+++ b/xCAT-server/lib/xcat/plugins/tabutils.pm
@@ -760,7 +760,9 @@ sub nodech
                                 if (($key eq 'groups') && ($op eq '=')) {
                                     if (scalar(@grplist) == 0) { # Do not call $grptab->getAllEntries for each node, performance issue.
                                         $grptab = xCAT::Table->new('nodegroup');
-                                        @grplist = @{$grptab->getAllEntries()};
+                                        if ($grptab) {
+                                            @grplist = @{$grptab->getAllEntries()};
+                                        }
                                     }
                                     my @grps = split(/,/, $val);
                                     foreach my $grp (@grps) {