diff --git a/release/tools/ec2.conf b/release/tools/ec2.conf
index a273449843ee..1ece644b37ee 100644
--- a/release/tools/ec2.conf
+++ b/release/tools/ec2.conf
@@ -6,7 +6,7 @@
 # Packages to install into the image we're creating.  This is a deliberately
 # minimalist set, providing only the packages necessary to bootstrap further
 # package installation as specified via EC2 user-data.
-export VM_EXTRA_PACKAGES="ec2-scripts firstboot-freebsd-update firstboot-pkgs"
+export VM_EXTRA_PACKAGES="ec2-scripts firstboot-freebsd-update firstboot-pkgs dual-dhclient"
 
 # Set to a list of third-party software to enable in rc.conf(5).
 export VM_RC_LIST="ec2_configinit ec2_fetchkey ec2_ephemeralswap ec2_loghostkey firstboot_freebsd_update firstboot_pkgs"
@@ -39,8 +39,9 @@ vm_extra_pre_umount() {
 	# time; expand our filesystem to fill the disk.
 	echo 'growfs_enable="YES"' >> ${DESTDIR}/etc/rc.conf
 
-	# EC2 instances use DHCP to get their network configuration.
-	echo 'ifconfig_DEFAULT="SYNCDHCP"' >> ${DESTDIR}/etc/rc.conf
+	# EC2 instances use DHCP to get their network configuration.  IPv6
+	# requires accept_rtadv.
+	echo 'ifconfig_DEFAULT="SYNCDHCP accept_rtadv"' >> ${DESTDIR}/etc/rc.conf
 
 	# Unless the system has been configured via EC2 user-data, the user
 	# will need to SSH in to do anything.
@@ -51,6 +52,10 @@ vm_extra_pre_umount() {
 	# via EC2 user-data.
 	echo 'firstboot_pkgs_list="awscli"' >> ${DESTDIR}/etc/rc.conf
 
+	# Enable IPv6 on all interfaces, and use DHCP on both IPv4 and IPv6.
+	echo 'ipv6_activate_all_interfaces="YES"' >> ${DESTDIR}/etc/rc.conf
+	echo 'dhclient_program="/usr/local/sbin/dual-dhclient"' >> ${DESTDIR}/etc/rc.conf
+
 	# The EC2 console is output-only, so while printing a backtrace can
 	# be useful, there's no point dropping into a debugger or waiting
 	# for a keypress.