diff --git a/perl-xCAT-2.0/xCAT/Schema.pm b/perl-xCAT-2.0/xCAT/Schema.pm
index 5d957fe5a..fd7a70877 100644
--- a/perl-xCAT-2.0/xCAT/Schema.pm
+++ b/perl-xCAT-2.0/xCAT/Schema.pm
@@ -56,7 +56,7 @@ package xCAT::Schema;
   },
   mac => {
     cols => [qw(node interface mac comments disable)],
-    keys => [qw(node interface)],
+    keys => [qw(node)],
   },
   chain => {
     cols => [qw(node currstate currchain chain ondiscover comments disable)],
diff --git a/perl-xCAT-2.0/xCAT/Table.pm b/perl-xCAT-2.0/xCAT/Table.pm
index ca860c787..745c8ba63 100644
--- a/perl-xCAT-2.0/xCAT/Table.pm
+++ b/perl-xCAT-2.0/xCAT/Table.pm
@@ -159,16 +159,16 @@ sub new
     $self->{colnames} = \@{$self->{schema}->{cols}};
     my %otherargs  = @_;
     my $create     = $otherargs{'-create'};      #(scalar(@_) == 1 ? shift : 0);
-    my $autocommit = $otherargs{'-autocommit'};
+    $self->{autocommit} = $otherargs{'-autocommit'};
 
-    unless (defined($autocommit))
+    unless (defined($self->{autocommit}))
     {
-        $autocommit = 1;
+        $self->{autocommit} = 1;
     }
 
     my $class = ref($proto) || $proto;
-    my $dbuser="";
-    my $dbpass="";
+    $self->{dbuser}="";
+    $self->{dbpass}="";
 
     my $xcatcfg = (defined $ENV{'XCATCFG'} ? $ENV{'XCATCFG'} : '');
     if ($xcatcfg =~ /^$/)
@@ -210,13 +210,18 @@ sub new
     }
     else #Generic DBI
     {
-       ($self->{connstring},$dbuser,$dbpass) = split(/\|/,$xcatcfg);
+       ($self->{connstring},$self->{dbuser},$self->{dbpass}) = split(/\|/,$xcatcfg);
        $self->{connstring} =~ s/^dbi://;
        $self->{connstring} =~ s/^/dbi:/;
         #return undef;
     }
-    $self->{dbh} =
-      DBI->connect($self->{connstring}, $dbuser, $dbpass, {AutoCommit => $autocommit});
+    unless ($::XCAT_DBHS->{$self->{connstring},$self->{dbuser},$self->{dbpass},$self->{autocommit}}) { #= $self->{tabname};
+      $::XCAT_DBHS->{$self->{connstring},$self->{dbuser},$self->{dbpass},$self->{autocommit}} = 
+        DBI->connect($self->{connstring}, $self->{dbuser}, $self->{dbpass}, {AutoCommit => $self->{autocommit}});
+     }
+
+    $self->{dbh} = $::XCAT_DBHS->{$self->{connstring},$self->{dbuser},$self->{dbpass},$self->{autocommit}};
+      #DBI->connect($self->{connstring}, $self->{dbuser}, $self->{dbpass}, {AutoCommit => $autocommit});
     if ($xcatcfg =~ /^SQLite:/)
     {
         my $dbexistq =
@@ -1570,8 +1575,8 @@ sub getTable
 sub close
 {
     my $self = shift;
-    if ($self->{dbh}) { $self->{dbh}->disconnect(); }
-    undef $self->{dbh};
+    #if ($self->{dbh}) { $self->{dbh}->disconnect(); }
+    #undef $self->{dbh};
     if ($self->{tabname} eq 'nodelist') {
        undef $self->{nodelist};
     } else {
@@ -1632,6 +1637,7 @@ sub open
 sub DESTROY
 {
     my $self = shift;
+    $self->{dbh} = '';
     undef $self->{dbh};
     #if ($self->{dbh}) { $self->{dbh}->disconnect(); undef $self->{dbh};}
     undef $self->{nodelist};    #Could be circular
diff --git a/perl-xCAT-2.0/xCAT/Utils.pm b/perl-xCAT-2.0/xCAT/Utils.pm
index 3676f8cd9..3ae4324e6 100644
--- a/perl-xCAT-2.0/xCAT/Utils.pm
+++ b/perl-xCAT-2.0/xCAT/Utils.pm
@@ -110,15 +110,11 @@ sub xfork {
 		return $rc;
 	}
 	unless ($rc) {
-          my %drivers = DBI->installed_drivers;
-          foreach my $drh (values %drivers) {
-            foreach (@{$drh->{ChildHandles}}) {
-                $_->{InactiveDestroy} = 1;
-            }
-            foreach (@{$drh->{ChildHandles}}) {
-                undef $_;
-            }
-	  }
+          #my %drivers = DBI->installed_drivers;
+          foreach (values %{$::XCAT_DBHS}) { #@{$drh->{ChildHandles}}) {
+              $_->{InactiveDestroy} = 1;
+	      undef $_;
+          }
         }
 	return $rc;
 }
diff --git a/xCAT-server-2.0/share/xcat/install/centos/compute.tmpl b/xCAT-server-2.0/share/xcat/install/centos/compute.tmpl
index 17fc262c9..f0a39b8e2 100644
--- a/xCAT-server-2.0/share/xcat/install/centos/compute.tmpl
+++ b/xCAT-server-2.0/share/xcat/install/centos/compute.tmpl
@@ -124,7 +124,6 @@ skipx
 #rootpw --iscrypted XaLGAVe1C41x2
 #rootpw XaLGAVe1C41x2 --iscrypted
 rootpw --iscrypted #CRYPT:passwd:key=system,username=root:password#
-#rootpw --iscrypted #COMMAND:perl -e 'print crypt("#TABLE:passwd.tab:rootpw:1#","Xa") . "\n";'p#
 
 #
 # NIS setup: auth --enablenis --nisdomain sensenet 
diff --git a/xCAT-server-2.0/share/xcat/install/fedora/compute.tmpl b/xCAT-server-2.0/share/xcat/install/fedora/compute.tmpl
index da3de7918..84a7ba73d 100644
--- a/xCAT-server-2.0/share/xcat/install/fedora/compute.tmpl
+++ b/xCAT-server-2.0/share/xcat/install/fedora/compute.tmpl
@@ -125,7 +125,6 @@ skipx
 #rootpw --iscrypted XaLGAVe1C41x2
 #rootpw XaLGAVe1C41x2 --iscrypted
 rootpw --iscrypted #CRYPT:passwd:key=system,username=root:password#
-#rootpw --iscrypted #COMMAND:perl -e 'print crypt("#TABLE:passwd.tab:rootpw:1#","Xa") . "\n";'p#
 
 #
 # NIS setup: auth --enablenis --nisdomain sensenet 
diff --git a/xCAT-server-2.0/share/xcat/install/rh/compute.tmpl b/xCAT-server-2.0/share/xcat/install/rh/compute.tmpl
index e967eb2f6..a1bbd17ac 100644
--- a/xCAT-server-2.0/share/xcat/install/rh/compute.tmpl
+++ b/xCAT-server-2.0/share/xcat/install/rh/compute.tmpl
@@ -125,7 +125,6 @@ skipx
 #rootpw --iscrypted XaLGAVe1C41x2
 #rootpw XaLGAVe1C41x2 --iscrypted
 rootpw --iscrypted #CRYPT:passwd:key=system,username=root:password#
-#rootpw --iscrypted #COMMAND:perl -e 'print crypt("#TABLE:passwd.tab:rootpw:1#","Xa") . "\n";'p#
 
 #
 # NIS setup: auth --enablenis --nisdomain sensenet