diff --git a/xCAT-nbroot/xcat-core-nbroot.spec b/xCAT-nbroot/xcat-core-nbroot.spec
index 69ecab7be..b0eacfebc 100644
--- a/xCAT-nbroot/xcat-core-nbroot.spec
+++ b/xCAT-nbroot/xcat-core-nbroot.spec
@@ -51,6 +51,12 @@ chmod 755 etc/init.d/S40network bin/getdestiny bin/getdestiny.awk bin/getipmi bi
 cd -
 
 
+%post
+if [ "$1" == "2" ]; then #only on upgrade, as on install it's probably not going
+                         #to work...
+   . /etc/profile.d/xcat.sh
+   mknb %{tarch}
+fi
 
 %Files
 %defattr(-,root,root)
diff --git a/xCAT-server-2.0/lib/xcat/plugins/mknb.pm b/xCAT-server-2.0/lib/xcat/plugins/mknb.pm
index 84ad3e62c..a778dfb9c 100644
--- a/xCAT-server-2.0/lib/xcat/plugins/mknb.pm
+++ b/xCAT-server-2.0/lib/xcat/plugins/mknb.pm
@@ -41,7 +41,7 @@ sub process_request {
    my $installdir = "/install";
    my $tftpdir = "/tftpboot";
    if (scalar(@{$request->{arg}}) != 1) {
-      $callback->({error=>"Need to specifiy architecture (x86_64 or ppc64)"},{errorcode=>[1]});
+      $callback->({error=>"Need to specifiy architecture (x86, x86_64 or ppc64)"},{errorcode=>[1]});
       return;
    }
    my $arch = $request->{arg}->[0];
@@ -106,8 +106,27 @@ sub process_request {
          chmod(0644,"$tftpdir/pxelinux.0");
       }
    }
+   my $dopxe=0;
    foreach (keys %{$hexnets}) {
-      if ($arch =~ /x86/) {
+      $dopxe=0;
+      if ($arch =~ /x86/) { #only do pxe if just x86 or x86_64 and no x86
+         if ($arch =~ /x86_64/) {
+            if (-r "$tftpdir/pxelinux.cfg/".uc($_)) {
+               my $pcfg;
+               open($pcfg,"<","$tftpdir/pxelinux.cfg/".uc($_));
+               my @pcfgcontents = <$pcfg>;
+               close($pcfg);
+               if (grep (/x86_64/,@pcfgcontents)) {
+                  $dopxe=1;
+               }
+            } else {
+               $dopxe=1;
+            }
+         } else {
+            $dopxe=1;
+         }
+      }
+      if ($dopxe) {
          open($cfgfile,">","$tftpdir/pxelinux.cfg/".uc($_));
          print $cfgfile "DEFAULT xCAT\n";
          print $cfgfile "  LABEL xCAT\n";
diff --git a/xCAT/xCAT.spec b/xCAT/xCAT.spec
index ff2c2d65e..81c82ab43 100644
--- a/xCAT/xCAT.spec
+++ b/xCAT/xCAT.spec
@@ -22,7 +22,7 @@ Requires: atftp dhcp httpd nfs-utils expect conserver fping bind perl-XML-Parser
 %endif
 
 %ifarch i386 i586 i686 x86 x86_64
-Requires: xCAT-nbroot-oss-x86_64 xCAT-nbroot-core-x86_64 xCAT-nbkernel-x86_64 syslinux
+Requires: xCAT-nbroot-oss-x86 xCAT-nbroot-core-x86 xCAT-nbkernel-x86 xCAT-nbroot-oss-x86_64 xCAT-nbroot-core-x86_64 xCAT-nbkernel-x86_64 syslinux
 Requires: ipmitool >= 1.8.9
 %endif
 
@@ -163,6 +163,7 @@ if [ "$1" = "1" ]; then #Only if installing for the fist time..
     XCATROOT=$RPM_INSTALL_PREFIX0 /etc/init.d/xcatd start
     if [ -x $RPM_INSTALL_PREFIX0/sbin/mknb ]; then
 %ifarch i386 i586 i686 x86 x86_64
+       $RPM_INSTALL_PREFIX0/sbin/mknb x86
        $RPM_INSTALL_PREFIX0/sbin/mknb x86_64
 %endif
 %ifarch ppc ppc64