diff --git a/xCAT-server/lib/xcat/plugins/aixinstall.pm b/xCAT-server/lib/xcat/plugins/aixinstall.pm
index 644f141da..fbba569c4 100644
--- a/xCAT-server/lib/xcat/plugins/aixinstall.pm
+++ b/xCAT-server/lib/xcat/plugins/aixinstall.pm
@@ -771,11 +771,163 @@ sub nimnodeset
     $error = 0;
     foreach my $node (@nodelist)
     {
+        # set the NIM machine type
+        my $type = "standalone";
+        if ($imagehash{$image_name}{nimtype})
+        {
+            $type = $imagehash{$image_name}{nimtype};
+        }
+        chomp $type;
 
         # get the image name to use for this node
         my $image_name = $nodeosi{$node};
         chomp $image_name;
 
+
+        # define the node if it doesn't exist
+        if (!grep(/^$node$/, @machines))
+        {
+
+            # get, check the node IP
+            # TODO - need IPv6 update
+            #my $IP = inet_ntoa(inet_aton($node));
+            my $IP = xCAT::NetworkUtils->getipaddr($node);
+            chomp $IP;
+
+            unless (($IP =~ /\d+\.\d+\.\d+\.\d+/) || ($IP =~ /:/))
+            {
+                my $rsp;
+                push @{$rsp->{data}},
+                  "$Sname: Could not get valid IP address for node $node.\n";
+                xCAT::MsgUtils->message("E", $rsp, $callback);
+                $error++;
+                push(@nodesfailed, $node);
+                next;
+            }
+            # could be diskful
+            # mask, gateway, cosi, root, dump, paging
+            # TODO - need to fix this check for shared_root
+            if (   !$nethash{$node}{'mask'}
+                || !$nethash{$node}{'gateway'}
+                || !$imagehash{$image_name}{spot})
+            {
+                my $rsp;
+                push @{$rsp->{data}},
+                  "$Sname: Missing required information for node \'$node\'.\n";
+                xCAT::MsgUtils->message("E", $rsp, $callback);
+                $error++;
+                push(@nodesfailed, $node);
+                next;
+            }
+
+            # set some default values
+            # overwrite with cmd line values - if any
+            my $speed  = "100";
+            my $duplex = "full";
+            if ($attrs{duplex})
+            {
+                $duplex = $attrs{duplex};
+            }
+            if ($attrs{speed})
+            {
+                $speed = $attrs{speed};
+            }
+
+            # define the node
+            my $mac_or_local_link_addr;
+            my $adaptertype;
+            my $netmask;
+            my $if = 1;
+            my $netname;
+
+            # need a short hostname to define in NIM
+            my $nodeshorthost;
+            ($nodeshorthost = $node) =~ s/\..*$//;
+            chomp $nodeshorthost;
+
+            my $nim_name = $nodeshorthost;
+
+            # Use -F to workaround ping time during diskless node defined in nim
+            my $defcmd = "/usr/sbin/nim -Fo define -t $type ";
+
+            $objhash{$node}{'mac'} =~ s/://g;    # strip out colons if any
+            my @macs = split /\|/, $objhash{$node}{'mac'};
+            foreach my $mac (@macs)
+            {
+
+                if (xCAT::NetworkUtils->getipaddr($nodeshorthost) =~ /:/) #ipv6 node
+                {
+                    $mac_or_local_link_addr = xCAT::NetworkUtils->linklocaladdr($mac);
+                    $adaptertype = "ent6";
+                    $netmask = xCAT::NetworkUtils->prefixtomask($nethash{$node}{'mask'});
+                } else {
+                    $mac_or_local_link_addr = $mac;
+                    # only support Ethernet for management interfaces
+                    if ($nethash{$node}{'mgtifname'} =~ /hf/)
+                    {
+                        $adaptertype = "hfi0";
+                    } else {
+                        $adaptertype = "ent";
+                    }
+                    $netmask = $nethash{$node}{'mask'};
+                }
+
+                $netname = $nethash{$node}{'netname'};
+
+                if ($::NEWNAME)
+                {
+                    $defcmd .= "-a if$if='find_net $nodeshorthost 0' ";
+                } else
+                {
+                    $defcmd .=
+
+
+                          "-a if$if='find_net $nodeshorthost $mac_or_local_link_addr $adaptertype' ";
+                }
+
+                $defcmd .= "-a cable_type$if=N/A ";
+                $if = $if + 1;
+            }
+
+            $defcmd .= "-a netboot_kernel=mp ";
+
+            if ($nethash{$node}{'mgtifname'} !~ /hf/)
+            {
+                $defcmd .=
+                    "-a net_definition='$adaptertype $netmask $nethash{$node}{'gateway'}' ";
+                $defcmd .= "-a net_settings1='$speed $duplex' ";
+            }
+
+            $defcmd .= "$nim_name  2>&1";
+            if ($::VERBOSE)
+            {
+                my $rsp;
+                push @{$rsp->{data}}, "$Sname: Creating NIM node definition.\n";
+                xCAT::MsgUtils->message("I", $rsp, $callback);
+            } else {
+                               my $rsp;
+                               push @{$rsp->{data}}, "$Sname: Creating NIM client definition \'$nim_name.\'\n";
+                               xCAT::MsgUtils->message("I", $rsp, $callback);
+                       }
+            my $output = xCAT::Utils->runcmd("$defcmd", -1);
+            if ($::RUNCMD_RC != 0)
+            {
+                my $rsp;
+                push @{$rsp->{data}},
+                  "$Sname: Could not create a NIM definition for \'$nim_name\'.\n";
+                if ($::VERBOSE)
+                {
+                    push @{$rsp->{data}}, "$output";
+                }
+                xCAT::MsgUtils->message("E", $rsp, $callback);
+                $error++;
+                push(@nodesfailed, $node);
+                next;
+            }
+        }
+
+
+
         # check if node is in ready state
         my $shorthost;
         ($shorthost = $node) =~ s/\..*$//;
@@ -864,7 +1016,13 @@ sub nimnodeset
         my $nim_name;
         ($nim_name = $node) =~ s/\..*$//;
         chomp $nim_name;
-        if (!grep(/^$nim_name$/, @machines))
+
+        # read machines again to make sure they have been defined
+        my $cmd =
+          qq~/usr/sbin/lsnim -c machines | /usr/bin/cut -f1 -d' ' 2>/dev/null~;
+        my @updatedmachines = xCAT::Utils->runcmd("$cmd", -1);
+
+        if (!grep(/^$nim_name$/, @updatedmachines))
         {
             my $rsp;
             push @{$rsp->{data}},