diff --git a/xCAT-server/lib/xcat/plugins/mknb.pm b/xCAT-server/lib/xcat/plugins/mknb.pm
index 01ddc5b95..baaac6e97 100644
--- a/xCAT-server/lib/xcat/plugins/mknb.pm
+++ b/xCAT-server/lib/xcat/plugins/mknb.pm
@@ -828,7 +828,7 @@ sub process_request {
             open($cfg, ">", "$tftpdir/xcat/xnba/nets/$net");
             print $cfg "#!gpxe\n";
             if ($invisibletouch) {
-                print $cfg 'imgfetch -n kernel http://${next-server}'.$portsuffix.'/tftpboot/xcat/genesis.kernel.' . "$arch xcatd=" . $xcatd_address . ":$xcatdport $consolecmdline BOOTIF=01-" . '${netX/machyp}' . "\n";
+                print $cfg 'imgfetch -n kernel http://${next-server}'.$portsuffix.'/tftpboot/xcat/genesis.kernel.' . "$arch xcatd=" . $xcatd_address . ":$xcatdport $consolecmdline BOOTIF=01-" . '${netX/mac:hexhyp}' . "\n";
                 print $cfg 'imgfetch -n nbfs http://${next-server}'.$portsuffix . "$initrd_file\n";
             } else {
                 print $cfg 'imgfetch -n kernel http://${next-server}'.$portsuffix.'/tftpboot/xcat/nbk.' . "$arch xcatd=" . $xcatd_address . ":$xcatdport $consolecmdline\n";