Fix several glitches in IPv6-related knobs:

- ipv6_enable + ipv6_gateway_enable should unset ACCEPT_RTADV by default for
  backward compatibility.

- Configurations in ipv6_prefix_IF should be recognized even if there is no
  ifconfig_IF_ipv6.

- DAD wait should be performed at once, not on a per-interface basis, if
  possible.  This fixes an issue that a system with a lot of IPv6-capable
  interfaces takes too long for booting.

MFC after:	1 week

1 files changed, 10 insertions, 0 deletions

diff --git a/etc/rc.d/netif b/etc/rc.d/netif
index 01da302c5dfe..b584f1584096 100755
--- a/etc/rc.d/netif
+++ b/etc/rc.d/netif
@@ -123,16 +123,26 @@ network_common()
 		_cooked_list="`list_net_interfaces`"
 	fi
 
+	_dadwait=
 	_fail=
 	_ok=
 	for ifn in ${_cooked_list}; do
 		if ${_func} ${ifn} $2; then
 			_ok="${_ok} ${ifn}"
+			if ipv6if ${ifn}; then
+				_dadwait=1
+			fi
 		else
 			_fail="${_fail} ${ifn}"
 		fi
 	done
 
+	# inet6 address configuration needs sleep for DAD.
+	if [ -n "${_dadwait}" ]; then
+		sleep `${SYSCTL_N} net.inet6.ip6.dad_count`
+		sleep 1
+	fi
+
 	_str=
 	if [ -n "${_ok}" ]; then
 		case ${_func} in