diff --git a/xCAT-genesis-builder/buildrpm b/xCAT-genesis-builder/buildrpm
index e774bb2c2..ae1d7a042 100755
--- a/xCAT-genesis-builder/buildrpm
+++ b/xCAT-genesis-builder/buildrpm
@@ -1,13 +1,47 @@
+# Build the xCAT-genesis-base rpm on a host system.
+# Option 1:  install the xCAT-genesis-builder rpm (that includes this file) on a system installed with
+#            the distro you want to use to build xCAT-genesis-base.
+# Option 2:  untar the root file system of the distro you want to use and then chroot into it and copy
+#            this whole dir into it somewhere (like /tmp).
+# Then run this script.  The optional 1st arg should be mcp if you are building against mcp.
+HOSTOS="$1"
 DIR=`dirname $0`
-mkdir -p /usr/share/dracut/modules.d/97xcat
-cp $DIR/* /usr/share/dracut/modules.d/97xcat
+DIR=`realpath $DIR`
+
+# get the input files for dracut in the right place
+DRACUTMODDIR=/usr/share/dracut/modules.d/97xcat
+mkdir -p $DRACUTMODDIR
+cp $DIR/* $DRACUTMODDIR
+if [ "$HOSTOS" = "mcp" ]; then
+	mv -f $DRACUTMODDIR/install.$HOSTOS $DRACUTMODDIR/install
+	mv -f $DRACUTMODDIR/installkernel.$HOSTOS $DRACUTMODDIR/installkernel
+fi
 mkdir -p /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/fs 
+
+# run dracut
+echo Creating the initramfs in /tmp/xcatgenesis.$$.rfs using dracut ...
 dracut -m "xcat base" -f /tmp/xcatgenesis.$$.rfs
+
+echo Expanding the initramfs into /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/fs ...
 cd /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/fs 
 zcat /tmp/xcatgenesis.$$.rfs|cpio -dumi
-cp /boot/vmlinuz-`uname -r` /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/kernel
+
+# add the kernel
+if [ "$HOSTOS" = "mcp" ]; then
+	echo Adding kernel /boot/vmlinuz-* ...
+	cp /boot/vmlinuz-* /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/kernel
+else
+	echo Adding kernel /boot/vmlinuz-`uname -r` ...
+	cp /boot/vmlinuz-`uname -r` /tmp/xcatgenesis.$$/opt/xcat/share/xcat/netboot/genesis/`uname -m`/kernel
+fi
 cd -
+
+# create tar file
+echo Tarring /tmp/xcatgenesis.$$/opt into ~/rpmbuild/SOURCES/xCAT-genesis-base-`uname -m`.tar.bz2 ...
 cd /tmp/xcatgenesis.$$
 tar jcf ~/rpmbuild/SOURCES/xCAT-genesis-base-`uname -m`.tar.bz2 opt
+
+# build the rpm
+echo Building xCAT-genesis-base rpm from ~/rpmbuild/SOURCES/xCAT-genesis-base-`uname -m`.tar.bz2 and $DIR/xCAT-genesis-base.spec ...
 rpmbuild -ba $DIR/xCAT-genesis-base.spec 
-rm -rf /usr/share/dracut/modules.d/97xcat
+rm -rf $DRACUTMODDIR
diff --git a/xCAT-genesis-scripts/xCAT-genesis-scripts.spec b/xCAT-genesis-scripts/xCAT-genesis-scripts.spec
index e29bc6eec..0c5abd353 100644
--- a/xCAT-genesis-scripts/xCAT-genesis-scripts.spec
+++ b/xCAT-genesis-scripts/xCAT-genesis-scripts.spec
@@ -56,14 +56,20 @@ rm opt/xcat/share/xcat/netboot/genesis/x86_64/fs/LICENSE.html
 cd -
 
 
+# Since this rpm is being installed/updated, we need to run mknb to combine it with
+# xCAT-genesis-base-x86_64, but mknb will not work during an initial install of xcat
+# until the xCAT meta pkg has run xcatconfig or xCATsn has started xcatd.  Use of a trigger
+# allows us to tell those pkgs to run the code below after they run their %post scriptlets.
+# (If xCAT or xCATsn is installed already, this trigger will run when xCAT-genesis-scripts
+# is installed/updated.)
+
 %post
-if [ "$1" == "2" -o -e /opt/xcat/sbin/mknb ]; then #only on upgrade, or if the rest of xcat is already installed
-	if [ -f "/proc/cmdline" ]; then   # prevent running it during install into chroot image
-   		. /etc/profile.d/xcat.sh
-   		echo mknb %{tarch}...
-   		mknb %{tarch}
-   	fi
-fi
+# Touch this file to tell the xCAT and xCATsn rpms that when they install/update they
+# should run mknb.  Tried to use rpm triggers, but in several cases the trigger would
+# get run multiple times.
+#echo "touching /etc/xcat/genesis-scripts-updated"
+touch /etc/xcat/genesis-scripts-updated
+
 
 %Files
 %defattr(-,root,root)
diff --git a/xCAT-server/lib/xcat/plugins/AAsn.pm b/xCAT-server/lib/xcat/plugins/AAsn.pm
index 70136c042..ce0aa6939 100644
--- a/xCAT-server/lib/xcat/plugins/AAsn.pm
+++ b/xCAT-server/lib/xcat/plugins/AAsn.pm
@@ -1248,19 +1248,19 @@ sub setup_TFTP
     }
     else
     {                         #if not mounting, have to regenerate....
-                              #first, run mknb to get nbfs and such going?
         my $cmdref;
-        use xCAT_plugin::mknb;
-        for my $architecture ("ppc64", "x86", "x86_64")
-        {
-            unless (-d "$::XCATROOT/share/xcat/netboot/$architecture")
-            {
-                next;
-            }
-            $cmdref->{command}->[0] = "mknb";
-            $cmdref->{arg}->[0]     = $architecture;
-            $doreq->($cmdref, \&xCAT::Client::handle_response);
-        }
+        # mknb is now run in xCATsn.spec
+        #use xCAT_plugin::mknb;
+        #for my $architecture ("ppc64", "x86", "x86_64")
+        #{
+        #    unless (-d "$::XCATROOT/share/xcat/netboot/$architecture")
+        #    {
+        #        next;
+        #    }
+        #    $cmdref->{command}->[0] = "mknb";
+        #    $cmdref->{arg}->[0]     = $architecture;
+        #    $doreq->($cmdref, \&xCAT::Client::handle_response);
+        #}
 
         #now, run nodeset enact on
         my $mactab = xCAT::Table->new('mac');
diff --git a/xCAT-server/sbin/xcatconfig b/xCAT-server/sbin/xcatconfig
index b3405b3c6..5156d75a1 100755
--- a/xCAT-server/sbin/xcatconfig
+++ b/xCAT-server/sbin/xcatconfig
@@ -405,9 +405,6 @@ if ($::INITIALINSTALL || $::FORCE)
         }
      }
 
-     # run mknb - only needed for Intel platforms for now
-     &mknb;
-
      # makenetworks and setup http
      &makenetworks;
      &setuphttp;
@@ -548,6 +545,7 @@ if ($::INITIALINSTALL || $::FORCE)
      my $linux_note =
       "xCAT is now running, it is recommended to tabedit networks \nand set a dynamic ip address range on any networks where nodes \nare to be discovered. Then, run makedhcp -n to create a new dhcpd \nconfiguration file, and \/etc\/init.d\/dhcpd restart. Either examine sample \nconfiguration templates, or write your own, or specify a value per \nnode with nodeadd or tabedit.";
      xCAT::MsgUtils->message('I', $linux_note);
+
    } else { #AIX
      # makenetworks
      &makenetworks;
@@ -559,6 +557,11 @@ if ($::INITIALINSTALL || $::FORCE)
 
 }    #End - more - Linux-only config
 
+# Run mknb to put xCAT-genesis-scripts-x86_64 and xCAT-genesis-base-x86_64 together and in /tftpboot
+if (($::INITIALINSTALL || $::UPDATEINSTALL) && $::osname eq 'Linux') {
+  &mknb;
+}
+
 END
 {
     # Remove xcatconfig itself from the inittab
@@ -1838,32 +1841,30 @@ sub setupLinuxexports
 
 =head3    mknb 
 	
-    creates a network boot root image on Linux 
+   Creates a network boot root image on Linux 
+   Run mknb to put xCAT-genesis-scripts-x86_64 and xCAT-genesis-base-x86_64 together and in /tftpboot
 
 =cut
 
 #-----------------------------------------------------------------------------
 sub mknb
 {
-    if ($::arch eq "x86_64" || $::arch eq "x86")
-    {
-        foreach my $ar (qw(x86_64))
-        {
-            my $cmd = "XCATBYPASS=Y $::XCATROOT/sbin/mknb $ar";
-            my $outref = xCAT::Utils->runcmd("$cmd", 0);
-            if ($::RUNCMD_RC != 0)
-            {
-                xCAT::MsgUtils->message('E',
-                          "The mknb $ar command returned error: $::RUNCMD_RC.");
-            }
-            else
-            {
-                xCAT::MsgUtils->message('I',
-                                "The mknb $ar command completed successfully.");
-            }
-        }
+  # The xCAT-genesis-scripts.spec file touches /etc/xcat/genesis-scripts-updated so we know to run
+  # mknb here.
+  if ($::arch eq "x86_64" && (-f '/etc/xcat/genesis-scripts-updated') ) {
+    unlink '/etc/xcat/genesis-scripts-updated';
+    my $cmd = "$::XCATROOT/sbin/mknb $::arch";
+    xCAT::MsgUtils->message('I', "Running '$cmd', triggered by the installation/update of xCAT-genesis-scripts-x86_64 ...");
+    #my $outref = xCAT::Utils->runcmd("$cmd", 0);
+    system($cmd);
+    if ($? != 0) {
+      my $rc = $? >> 8;
+      xCAT::MsgUtils->message('E', "The 'mknb $::arch' command returned error code: $rc.");
     }
-
+    else {
+      xCAT::MsgUtils->message('I', "The 'mknb $::arch' command completed successfully.");
+    }
+  }
 }
 
 #-----------------------------------------------------------------------------
diff --git a/xCAT/xCAT.spec b/xCAT/xCAT.spec
index fa0285aa0..23832897a 100644
--- a/xCAT/xCAT.spec
+++ b/xCAT/xCAT.spec
@@ -56,7 +56,7 @@ Requires: conserver-xcat
 %endif
 
 %ifarch i386 i586 i686 x86 x86_64
-Requires: syslinux xCAT-genesis-x86_64 elilo-xcat
+Requires: syslinux xCAT-genesis-scripts-x86_64 elilo-xcat
 Requires: ipmitool-xcat >= 1.8.9
 Requires: xnba-undi
 %endif
diff --git a/xCATsn/xCATsn.spec b/xCATsn/xCATsn.spec
index a26cbf340..4ed20d254 100644
--- a/xCATsn/xCATsn.spec
+++ b/xCATsn/xCATsn.spec
@@ -51,7 +51,7 @@ Requires: conserver-xcat
 %endif
 
 %ifarch i386 i586 i686 x86 x86_64
-Requires: syslinux xCAT-genesis-x86_64 elilo-xcat
+Requires: syslinux xCAT-genesis-scripts-x86_64 elilo-xcat
 Requires: ipmitool-xcat >= 1.8.9
 Requires: xnba-undi
 %endif
@@ -177,6 +177,23 @@ fi
 
 %endif
 
+# Run mknb if xCAT-genesis-scripts-x86_64 changed
+%ifos linux
+# prevent running it during install into chroot image and only run it if xCAT-genesis-scripts-x86_64
+# was recently updated.
+if [ -f "/proc/cmdline" -a -f "/etc/xcat/genesis-scripts-updated" ]; then
+  rm -f /etc/xcat/genesis-scripts-updated
+  # On the SN do not run mknb if we are sharing /tftpboot with the MN
+  SHAREDTFTP=`/opt/xcat/sbin/tabdump site | grep sharedtftp | cut -d'"' -f 4`
+  if [ "$SHAREDTFTP" != "1" ]; then
+      . /etc/profile.d/xcat.sh
+      echo Running '"'mknb %{tarch}'"', triggered by the installation/update of xCAT-genesis-scripts-x86_64 ...
+      mknb %{tarch}
+    fi
+fi
+%endif
+
+
 %clean
 
 %files