Index: contrib/hyperv/tools/scripts/hyperv_vfattach
===================================================================
--- /dev/null
+++ contrib/hyperv/tools/scripts/hyperv_vfattach
@@ -0,0 +1,49 @@
+#!/bin/sh
+
+#
+# If transparent VF is enabled, don't do anything.
+#
+
+sysctl -n hw.hn.vf_transparent > /dev/null 2>&1
+if [ $? -ne 0 ]
+then
+	# Old kernel; no transparent VF.
+	vf_transparent=0
+else
+	vf_transparent=`sysctl -n hw.hn.vf_transparent`
+fi
+
+if [ $vf_transparent -ne 0 ]
+then
+	exit 0
+fi
+
+#
+# Check to see whether $1 is a VF or not.
+# If $1 is a VF, bring it up now.
+#
+
+sysctl -n hw.hn.vflist > /dev/null 2>&1
+if [ $? -ne 0 ]
+then
+	# Old kernel; nothing could be done properly.
+	exit 0
+fi
+
+iface=$1
+vf_list=`sysctl -n hw.hn.vflist`
+
+for vf in $vf_list
+do
+	if [ $vf = $iface ]
+	then
+		#
+		# Linger a little bit mainly to make sure
+		# that $iface is fully attached.
+		#
+		sleep 2
+
+		ifconfig $iface up
+		break
+	fi
+done
Index: contrib/hyperv/tools/scripts/hyperv_vfup
===================================================================
--- /dev/null
+++ contrib/hyperv/tools/scripts/hyperv_vfup
@@ -0,0 +1,119 @@
+#!/bin/sh
+
+. /etc/rc.subr
+. /etc/network.subr
+
+load_rc_config netif
+
+#
+# Customized per-interface setup, e.g. hyperv_vfup.hn1
+#
+# NOTE-CUSTOMIZE:
+# Comment this out, if this script is used as template
+# for the customized per-interface setup.
+#
+if [ -f /usr/libexec/hyperv/hyperv_vfup.$1 ]
+then
+	/usr/libexec/hyperv/hyperv_vfup.$1
+	exit $?
+fi
+
+# NOTE-CUSTOMIZE:
+#hn=${0##*.}
+hn=$1
+hn_unit=`echo $hn | sed 's/[^0-9]*//g'`
+
+vf=`sysctl -n dev.hn.$hn_unit.vf`
+if [ ! $vf ]
+then
+	# Race happened; VF was removed, before we ran.
+	echo "$hn: VF was detached"
+	exit 0
+fi
+
+#
+# Create laggX for hnX.
+# Add VF and hnX to laggX.
+#
+
+lagg=lagg$hn_unit
+
+ifconfig $lagg > /dev/null 2>&1
+if [ $? -ne 0 ]
+then
+	#
+	# No laggX, create it now.
+	#
+	ifconfig $lagg create > /dev/null 2>&1
+	if [ $? -ne 0 ]
+	then
+		echo "$lagg creation failed"
+		exit 1
+	fi
+
+	#
+	# Configure laggX (failover), add hnX and VF to it.
+	#
+	ifconfig $lagg laggproto failover laggport $hn laggport $vf
+	ifconfig $lagg inet6 no_dad
+
+	#
+	# Stop dhclient on hnX, if any.
+	#
+	pidfile=/var/run/dhclient.$hn.pid
+	if [ -f $pidfile ]
+	then
+		kill -TERM `cat $pidfile`
+	fi
+
+	#
+	# Remove all configured IPv4 addresses on hnX, e.g.
+	# configured by dhclient.  laggX will take over the
+	# network operations.
+	#
+	while true
+	do
+		ifconfig $hn -alias > /dev/null 2>&1
+		if [ $? -ne 0 ]
+		then
+			break
+		fi
+	done
+
+	# TODO: Remove IPv6 addresses on hnX
+
+	#
+	# Use hnX's configuration for laggX
+	#
+	# NOTE-CUSTOMIZE:
+	# If this script is used as template for the customized
+	# per-interface setup, replace this with whatever you
+	# want to do with the laggX.
+	#
+	if dhcpif $hn;
+	then
+		ifconfig $lagg up
+		if syncdhcpif $hn;
+		then
+			dhclient $lagg
+		else
+			dhclient -b $lagg
+		fi
+	else
+		ifconfig_args=`ifconfig_getargs $hn`
+		if [ -n "$ifconfig_args" ]
+		then
+			ifconfig $lagg $ifconfig_args
+		fi
+	fi
+else
+	#
+	# laggX exists.  Check whether VF was there or not.
+	# If VF was not added to laggX, add it now.
+	#
+	ifconfig $lagg | grep "laggport: $vf" > /dev/null 2>&1
+	if [ $? -ne 0 ]
+	then
+		ifconfig $lagg laggport $vf
+	fi
+fi
Index: etc/devd/hyperv.conf
===================================================================
--- etc/devd/hyperv.conf
+++ etc/devd/hyperv.conf
@@ -33,3 +33,15 @@
 	match "cdev"		"hv_fsvss_dev";
 	action "pkill -x hv_vss_daemon";
 };
+
+notify 10 {
+	match "system"		"HYPERV_NIC_VF";
+	match "type"		"VF_UP";
+	action "/usr/libexec/hyperv/hyperv_vfup $subsystem";
+};
+
+notify 10 {
+	match "system"		"ETHERNET";
+	match "type"		"IFATTACH";
+	action "/usr/libexec/hyperv/hyperv_vfattach $subsystem";
+};
Index: libexec/hyperv/Makefile
===================================================================
--- libexec/hyperv/Makefile
+++ libexec/hyperv/Makefile
@@ -5,5 +5,6 @@
 BINDIR=		${LIBEXECDIR}/hyperv
 
 SCRIPTS=	hv_set_ifconfig hv_get_dns_info hv_get_dhcp_info
+SCRIPTS+=	hyperv_vfattach hyperv_vfup
 
 .include <bsd.prog.mk>