diff --git a/xCAT-server/lib/xcat/plugins/debian.pm b/xCAT-server/lib/xcat/plugins/debian.pm
index 510db7afa..623503b24 100644
--- a/xCAT-server/lib/xcat/plugins/debian.pm
+++ b/xCAT-server/lib/xcat/plugins/debian.pm
@@ -770,7 +770,7 @@ sub mkinstall
 	    #}
 	        
 	    $kcmdline .= " xcatd=".$instserver;
-	    $kcmdline .= " mirror/http/hostname=".$instserver;
+#	    $kcmdline .= " mirror/http/hostname=".$instserver;
             if ($maxmem) {
                 $kcmdline.=" mem=$maxmem";
             }
diff --git a/xCAT-server/share/xcat/install/debian/initoverlay/lib/debian-installer-startup.d/S10detectnic b/xCAT-server/share/xcat/install/debian/initoverlay/lib/debian-installer-startup.d/S10detectnic
index 3b0c63317..d17504dfc 100644
--- a/xCAT-server/share/xcat/install/debian/initoverlay/lib/debian-installer-startup.d/S10detectnic
+++ b/xCAT-server/share/xcat/install/debian/initoverlay/lib/debian-installer-startup.d/S10detectnic
@@ -4,6 +4,7 @@ if echo $BOOTMAC|grep BOOTIF= > /dev/null; then
         for dir in /sys/class/net/*; do
                 if grep -i $BOOTMAC $dir/address > /dev/null; then
                         debconf-set netcfg/choose_interface `basename $dir`
+			echo "d-i netcfg/choose_interface select `basename $dir`" >> /preseed.cfg
                 fi
         done
 fi
diff --git a/xCAT-server/share/xcat/install/scripts/pre.ubuntu b/xCAT-server/share/xcat/install/scripts/pre.ubuntu
index 0f1cd4cef..95c95ece9 100644
--- a/xCAT-server/share/xcat/install/scripts/pre.ubuntu
+++ b/xCAT-server/share/xcat/install/scripts/pre.ubuntu
@@ -4,11 +4,17 @@ if [ ! -c /dev/vcs ]; then
     mknod /dev/vcs c 7 0
 fi
 
+while [ -z "$instdisk" ]; do
+VIRTDISKS=`ls /dev/vd*|wc -l`
+if [ $VIRTDISKS -gt 0 ]; then 
 for disk in /dev/vd*[^0-9]; do
 	if [ -z "$firstdirectdisk" ]; then firstdirectdisk=$disk; fi #remember first disk as a guess of medium resort
 	#no edd_id in debian installer, no edd hints supported
 done
+fi
 if [ -z "$firstdirectdisk" ]; then
+	SCSIDISKS=`ls /dev/sd*|wc -l`
+	if [ $SCSIDISKS -gt 0 ]; then 
 	for disk in /dev/sd*[^0-9]; do
 		currdriver=`udevadm info --attribute-walk --name $disk |grep DRIVERS|grep -v '""'|grep -v '"sd"'|head -n 1|sed -e 's/[^"]*"//' -e 's/"//'`
 		case "$currdriver" in
@@ -23,6 +29,7 @@ if [ -z "$firstdirectdisk" ]; then
 				;;
 		esac
 	done
+	fi
 fi
 if [ -z "$instdisk" ]; then
         if [ ! -z "$firstdirectdisk" ]; then
@@ -33,7 +40,9 @@ if [ -z "$instdisk" ]; then
                 instdisk=$firstdisk
         fi
 fi
-debconf-set partman-auto/disk "$instdisk"
+if [ ! -z "$instdisk" ]; then debconf-set partman-auto/disk "$instdisk"; fi
+sleep 0.1
+done &