diff --git a/utils/he_ipv6/TODO b/utils/he_ipv6/TODO
index 49b2d62..ad27de4 100644
--- a/utils/he_ipv6/TODO
+++ b/utils/he_ipv6/TODO
@@ -1,4 +1,3 @@
-* fix creds
-** needs user/password, and the updateKey is unique per-tunnel so move it into an element in there.
-** need to get user/password into HEConf somehow. if i can get ?tid= working for the URL, that'd be perfect.
-^ need to use updateKey for tunnel-specific xml
+DHCPv6:
+* NTP server in <ra>? (dnsmasq: option6:ntpserver,...)
+* bootfile-(url|param) in <ra>? (dnsmasq: option6:*)
diff --git a/utils/he_ipv6/config.py b/utils/he_ipv6/config.py
index b44f165..fb4df2b 100644
--- a/utils/he_ipv6/config.py
+++ b/utils/he_ipv6/config.py
@@ -233,6 +233,12 @@ class Config(BaseConfig):
             tun_creds_id = tun_xml.attrib['creds']
             creds = self.creds[tun_creds_id]
             update_key = tun_xml.find('updateKey').text.strip()
+            # TODO: do I instead want to use HEConfig() and fetch the single unified config?
+            # Pros:
+            #   * I wouldn't completely die on a misconfigured tunnel in the user config.
+            # Cons:
+            #   * We'd have to skip missing tunnels (bad auth at HE, etc.)
+            #   * We would use more memory and take more time during init.
             he_conf = HETunnelConfig(tun_id, creds, update_key)
             tun = tunnel.Tunnel(tun_xml, he_conf, self.creds[tun_creds_id])
             self.tunnels[tun_id] = tun
diff --git a/utils/he_ipv6/example.tunnelbroker.xml b/utils/he_ipv6/example.tunnelbroker.xml
index 94667c3..c00ea72 100644
--- a/utils/he_ipv6/example.tunnelbroker.xml
+++ b/utils/he_ipv6/example.tunnelbroker.xml
@@ -48,6 +48,8 @@
       the "ra" child element under <assign> for further details.
       If you are using dnsmasq, you will want to edit dnsmasq.conf to *include* the generated file, most likely, as it
       only generates configuration for IPv6 options.
+      If this is not specified, NO RA/DHCPv6 management will be done *regardless* of any "re" child elements for below
+      "assign" objects.
       -->
       <assignments raProvider="dnsmasq">
         <!--
@@ -76,27 +78,50 @@
             resolver via RDNSS.
             It takes one (optional) attribute, "domains", which is a space-separated list of search domains, referred
             to in IPv6 as DNSSL (RFC 6106).
-            Note that Windows does not support DNSSL, and as such you must use dhcpv6's "domains" attribute if you wish
-            to do that.
+            Note that Windows does not support DNSSL properly, and as such you must use dnsmasq as your RA provider if
+            you wish to send search domains.
             If "domains" is specified but the element is false, the configuration will only advertise DNSSL and not
             RDNSS.
+            If you also specify dhcpv6 below and are using dnsmasq as your raProvider, then:
+              * the same domains will be sent via DHCPv6 option 24
+              * the same RDNSS resolver will be passed via DHCPv6 option 23
             -->
             <dns domains="foo.com bar.com">true</dns>
             <!--
-            Enable DHCPv6 for this assignment. Only used for dnsmasq, has no effect for radvd. As mentioned above, you
-            can also specify the "domains" attribute here as well, which will pass them via a regular DHCPv6 option.
-            If "domains" is specified but the element is false, only the domains will be passed.
-            Again, this only pertains to dnsmasq since radvd offers no DHCPv6 capabilities whatsoever.
+            Enable DHCPv6 for this assignment.
+
+            RADVD:
+            If you're using radvd, this will only enable the "AdvManagedFlag" and/or "AdvOtherConfigFlag" flags
+            (the "MO" bits). *No actual DHCPv6 address assignment will, or can, occur via radvd, only SLAAC.*
+
+            DNSMASQ:
+            To ensure maximum compatability with SLAAC, addresses will be served in the fixed range of:
+              <PREFIX>:dead:beef:cafe:[0000-FFFF]
+              (65535 addresses per prefix assignment, a.k.a. a /112).
+            Obviously your assignment's prefix length *must* be smaller than /112 (but should be at LEAST a /64 anyways
+            per RFC specification). Regardless of settings below, SLAAC *will* be offered if an "ra" element is defined.
+
+            It has an optional attribute, "advOther", which controls the "Other Configuration" bit.
+            The default is "false".
+            The "MO" bits (RFC 4861 § 4.2) are set accordingly:
+            ===================================================================================================
+            | Condition                         | M | O | Will addresses be assigned via DHCPv6 (if dnsmasq)? |
+            ===================================================================================================
+            | advOther="true", dhcpv6 is true   | 1 | 1 |                        Yes                          |
+            | advOther="true", dhcpv6 is false  | 0 | 1 |                        No                           |
+            | advOther="false", dhcpv6 is false | 0 | 0 |                        No                           |
+            | advOther="false", dhcpv6 is true  | 1 | 0 |                        Yes                          |
+            ===================================================================================================
             -->
-            <dhcpv6 domains="foo.com bar.com">true</dhcpv6>
+            <dhcpv6 advOther="true">true</dhcpv6>
           </ra>
         </assign>
-        <!-- Disable RA for this set (no "ra" chiled specified). -->
+        <!-- Disable RA for this set (no "ra" child specified). -->
         <assign prefix="64" alloc="48" iface="eth0"/>
         <assign prefix="64" alloc="48" iface="eth1">
           <ra tag="vmlan">
             <!-- This will use strictly SLAAC (if using dnsmasq, obviously - radvd only does SLAAC). -->
-            <dhcpv6>false</dhcpv6>
+            <dhcpv6 advOther="false">false</dhcpv6>
             <!-- And let clients choose their own resolver. -->
             <dns>false</dns>
           </ra>
@@ -105,7 +130,7 @@
           <ra tag="wlan">
             <!-- Only pass RDNSS resolvers. -->
             <dns>true</dns>
-            <dhcpv6>false</dhcpv6>
+            <dhcpv6 advOther="false">false</dhcpv6>
           </ra>
         </assign>
       </assignments>
@@ -116,7 +141,8 @@
       <assignments>
         <!--
         Uses the default prefix of /64 from your standard /64 allocation from Hurricane Electric.
-        Most users probably want this unless they're running an IPv6 router.
+        Most users probably want this if they just want IPv6 for their local computer unless they're running an IPv6
+        router.
         -->
         <assign iface="eth0"/>
       </assignments>
diff --git a/utils/he_ipv6/ra.py b/utils/he_ipv6/ra.py
index 1ddc623..62240e0 100644
--- a/utils/he_ipv6/ra.py
+++ b/utils/he_ipv6/ra.py
@@ -43,14 +43,8 @@ class RAConf(object):
         return(None)
 
     def generate(self, assignments):
-        ns = {}
-        for a in assignments:
-            if len(a.iface_addrs) > 3:
-                ns_addrs = a.iface_addrs[:3]
-            else:
-                ns_addrs = a.iface_addrs
-            ns[a.iface] = ns_addrs
-        self.cfgstr = self.tpl.render(assignments = assignments, nameservers = ns)
+        self.cfgstr = self.tpl.render(assignments = assignments)
+        return(None)
 
     def write(self):
         if not self.cfgstr:
diff --git a/utils/he_ipv6/ref b/utils/he_ipv6/ref
index f190ea3..f74a390 100644
--- a/utils/he_ipv6/ref
+++ b/utils/he_ipv6/ref
@@ -32,3 +32,10 @@
 # https://tools.ietf.org/html/rfc5175
 # https://tools.ietf.org/html/rfc6104
 # https://tools.ietf.org/html/rfc7772
+# DHCPv6
+# https://tools.ietf.org/html/rfc3315
+# https://tools.ietf.org/html/rfc3646
+# https://tools.ietf.org/html/rfc4649
+# https://tools.ietf.org/html/rfc8415
+##
+# https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipv6_fhsec/configuration/xe-3s/ip6f-xe-3s-book/ip6-rfcs.pdf
diff --git a/utils/he_ipv6/tpl/_common.j2 b/utils/he_ipv6/tpl/_common.j2
index 3ad3443..02486e9 100644
--- a/utils/he_ipv6/tpl/_common.j2
+++ b/utils/he_ipv6/tpl/_common.j2
@@ -5,12 +5,19 @@
 {%- set mtu = 1480 -%}
 {#- Minimum seconds allowed between sending unsolicited multicast RAs. 3 < x < (0.75 * max_inter) -#}
 {#- If using Mobile Extensions, 0.33 < x (0.75 * max_inter) -#}
-{%- set min_inter = 60 -%}
+{%- set min_inter = 10 -%}
 {#- Maximum seconds allowed between sending unsolicited multicast RAs. 4 < x < 1800 -#}
 {#- If using Mobile Extensions, 0.07 < x 1800 -#}
-{%- set max_inter = 600 -%}
+{%- set max_inter = 60 -%}
 {#- Minimum seconds between sending multicast RAs (solicited and unsolicited). -#}
 {#- If using Mobile Extensions, 0.03 < x -#}
 {%- set min_delay = 3 -%}
+{#- The lifetime associated with the default router in units of seconds. 0 OR max_inter < x < 9000 -#}
+{%- set lifetime = 9000 -%}
 {#- ## DHCPv6 OPTIONS ## -#}
-{#- Obviously, these only works for DNSMasq. -#}
+{#- Obviously, these only work for DNSMasq. -#}
+{#- How long the lease should last until a new one is requested. -#}
+{#- This is also used for *SLAAC addresses* in radvd. -#}
+{%- set lease_life = 21600 -%}{#- 6 hours -#}
+{#- How long should the options be valid for. -#}
+{%- set opts_life = lease_life -%}
diff --git a/utils/he_ipv6/tpl/dnsmasq.include.j2 b/utils/he_ipv6/tpl/dnsmasq.include.j2
index 09b100b..ecceed6 100644
--- a/utils/he_ipv6/tpl/dnsmasq.include.j2
+++ b/utils/he_ipv6/tpl/dnsmasq.include.j2
@@ -1,2 +1,49 @@
+{%- import '_common.j2' as common_opts with context -%}
 # This file should be *included* in your dnsmasq configuration.
+# Generated by he_ipv6.
+# See "dnsmasq --help dhcp6" for matching option identifers ("dhcp-option = ..., option6: <option>").
+enable-ra
+{% for assignment in assignments %}
+	{%- set assign_loop = loop -%}
+	{%- set ra_opts = [] -%}
+	{%- if assignment.ra_tag -%}
+		{%- set id_set = 'tag:' + assignment.ra_tag -%}
+		{%- set identifier = id_set -%}
+		{%- set do_listen = false -%}
+	{%- else -%}
+		{%- set id_set = 'set:' + assignment.iface -%}
+		{%- set identifier = 'tag:' + assignment.iface -%}
+		{%- set do_listen = true -%}
+	{%- endif -%}
+	{%- if assignment.ra_dns -%}
+		{%- do ra_opts.append('sa-names') -%}
+	{%- endif -%}
+	{%- if assignment.ra_dhcp is false -%}
+		{%- do ra_opts.append('ra-only') -%}
+		{%- if assignment.ra_other is true -%}
+			{%- do ra_opts.append('ra-stateless') -%}
+		{%- endif -%}
+	{%- endif -%}
+	{%- do ra_opts.append('slaac') -%}
+	{%- do ra_opts.append('ra-names') -%}
+# {{ assignment.iface }} assignment
+	{%- if do_listen %}
+listen = {{ assignment.iface_ll }}
+	{%- endif %}
+ra-param = {{ assignment.iface }}, mtu:{{ common_opts.mtu }}, high, {{ common_opts.min_delay }}, {{ common_opts.lifetime }}
+	{%- if assignment.ra_dhcp %}
+		{%- for block in assignment.iface_blocks %}
+dhcp-range = {{ id_set }}, {{ assignment.dhcp6_ranges[assign_loop.index0]|join(', ') }}, {{ ra_opts|join(', ') }}, {{ common_opts.lease_life }}
+		{%- endfor %}
+	{%- else %}
+dhcp-range = {{ id_set }}, ::, constructor={{ assignment.iface }}, {{ ra_opts|join(', ') }}, {{ common_opts.lease_life }}{#- TODO: check this. #}
+	{%- endif %}
+dhcp-option = {{ identifier }}, option6:information-refresh-time, {{ common_opts.opts_life }}
+	{%- if assignment.ra_dns %}
+dhcp-option = {{ identifier }}, option6:dns-server, [{{ assignment.iface_ll }}]
+	{%- endif %}
+	{%- if assignment.ra_domains %}
+dhcp-option = {{ identifier }}, option6:domain-search, {{ assignment.ra_domains|join(',') }}
+	{%- endif %}
 
+{% endfor %}
diff --git a/utils/he_ipv6/tpl/radvd.conf.j2 b/utils/he_ipv6/tpl/radvd.conf.j2
index 27a210f..2d82934 100644
--- a/utils/he_ipv6/tpl/radvd.conf.j2
+++ b/utils/he_ipv6/tpl/radvd.conf.j2
@@ -1,30 +1,44 @@
-# Generated by he_ipv6
-{% for assign in assignments %}
-	{% for assignment in assign.iface_blocks %}
+{%- import '_common.j2' as common_opts with context -%}
+# Generated by he_ipv6.
+# This may go wonky with multiple assignments on the same iface.
+{% for assignment in assignments %}
 interface {{ assignment.iface }} {
 	AdvSendAdvert on;
-	# Is it 1480 or 1280? Arch wiki says 1480, but everything else (older) says 1280.
-	# AdvLinkMTU 1280;
-	AdvLinkMTU 1480;
-	MinRtrAdvInterval 60;
-	MaxRtrAdvInterval 600;
-	AdvDefaultLifetime 9000;
+	AdvLinkMTU {{ common_opts.mtu }};
+	MinRtrAdvInterval {{ common_opts.min_inter }};
+	MaxRtrAdvInterval {{ common_opts.max_inter }};
+	MinDelayBetweenRAs {{ common_opts.min_delay }};
+	AdvDefaultLifetime {{ common_opts.lifetime }};
+	{%- if assignment.ra_dhcp is true -%}
+	AdvManagedFlag on;
+	{%- endif %}
+	{%- if assignment.ra_other is true -%}
+	AdvOtherConfigFlag on;
+	{%- endif %}
 
 		{%- for block in assignment.iface_blocks %}
 	prefix {{ block|string }} {
 		AdvOnLink on;
-			{%- if block.prefixlen == 64 %}
+			{%- if block.prefixlen <= 64 %}
 		AdvAutonomous on;
 			{%- endif %}
+		AdvValidLifetime {{ common_opts.lease_life }};
+		AdvPreferredLifetime {{ common_opts.lease_life }};
 		AdvRouterAddr off;
 	};
 		{%- endfor %}
 
-		{%- if ra.dns is true %}
-	RDNSS {{ nameservers[assignment.iface]|join(' ') }} {
+		{%- if assign.ra_dns is true %}
+	RDNSS {{ assignment.iface_ll }} {
+		AdvRDNSSLifetime {{ common_opts.opts_life }};
+	};
+		{%- endif %}
+
+		{%- if assign.ra_domains %}
+	DNSSL {{ assignment.ra_domains|join(' ') }} {
+		AdvDNSSLLifetime {{ common_opts.opts_life }};
 	};
 		{%- endif %}
 };
 
-	{%- endfor %}
 {%- endfor %}
diff --git a/utils/he_ipv6/tunnel.py b/utils/he_ipv6/tunnel.py
index b0009d2..8f00154 100644
--- a/utils/he_ipv6/tunnel.py
+++ b/utils/he_ipv6/tunnel.py
@@ -1,10 +1,11 @@
 import ipaddress
+import socket
 ##
 import netaddr
 from pyroute2 import IPRoute
 ##
-from . import utils
 from . import ra
+from . import utils
 
 
 class IP(object):
@@ -51,14 +52,28 @@ class IP6(IP):
 
 
 class Assignment(object):
-    def __init__(self, assign_xml, ra = False, dns = False, ra_provider = 'dnsmasq'):
+    def __init__(self,
+                 assign_xml,
+                 ra_dns = False,
+                 ra_dhcp = False,
+                 ra_other = False,
+                 ra_tag = None,
+                 ra_domains = None):
         self.xml = assign_xml
-        self.ra = ra
-        self.dns = dns
+        self.ra_dns = ra_dns
+        self.ra_tag = ra_tag
+        self.ra_other = ra_other
+        self.ra_domains = set()
+        if isinstance(ra_domains, list):
+            self.ra_domains.update(ra_domains)
+        elif isinstance(ra_domains, str):
+            self.ra_domains.update([i.lower().strip() for i in ra_domains if i.strip() != ''])
+        self.ra_dhcp = ra_dhcp
         self.iface = None
+        self.iface_ll = None
         self.iface_idx = None
-        self.iface_addrs = []
         self.iface_blocks = []
+        self.dhcp6_ranges = []
         self.alloc = None  # This must be set externally to a mapped Allocation instance
         self.alloc_id = None
         self.prefix = None
@@ -74,6 +89,16 @@ class Assignment(object):
         self.iface = _iface_txt.strip()
         ipr = IPRoute()
         self.iface_idx = ipr.link_lookup(ifname = self.iface)[0]
+        # Link-Local address
+        ll = ipr.get_addr(index = self.iface_idx,
+                          family = socket.AF_INET6,
+                          scope = 253)[0]['attrs']
+        addrs = dict(ll)['IFA_ADDRESS']
+        if isinstance(addrs, (list, tuple)):
+            addr = addrs[0]
+        else:
+            addr = addrs
+        self.iface_ll = addr
         ipr.close()
         return(None)
 
@@ -92,7 +117,11 @@ class Assignment(object):
         # NOT AN IP6 OBJECT!
         self.iface_blocks = self.alloc_block.extract_subnet(self.prefix, count = 1)
         for i in self.iface_blocks:
-            self.iface_addrs.append(IP6(str(next(i.iter_hosts())), 128))
+            # DHCPv6 range.
+            _base = str(i.ip).rstrip(':')
+            start = '{0}:dead:beef:cafe:0'.format(_base)
+            stop = '{0}:dead:beef:cafe:ffff'.format(_base)
+            self.dhcp6_ranges.append((start, stop))
         return(None)
 
 
@@ -114,11 +143,8 @@ class Tunnel(object):
         self.client = None
         self.server = None
         self.endpoint = None
-        self.ra = False
         self.ra_provider = None
-        self.ra_dns = False
-        self.ra_dhcp = False
-        self.allocations = {}  # This is a dict of {}[alloc.id] = Allocation obj
+        self.allocations = {}  # This is a dict of {}[alloc.id] = Allocation obj (as provided by HE)
         self.assignments = []  # This is a list of Assignment objs
         self.parse()
 
@@ -128,11 +154,27 @@ class Tunnel(object):
 
     def _assignments(self):
         _assigns_xml = self.xml.find('assignments')
-
-        self.enable_ra = utils.xml2bool(_assigns_xml.attrib.get('radvd', 'false'))
-        self.ra_dns = utils.xml2bool(_assigns_xml.attrib.get('radvdDns', 'false'))
+        self.ra_provider = _assigns_xml.attrib.get('raProvider')
         for _assign_xml in _assigns_xml.findall('assign'):
-            assign = Assignment(_assign_xml, ra = self.enable_ra, dns = self.ra_dns)
+            do_dns = False
+            domains = []
+            do_dhcp = False
+            ra_other = False
+            tag = _assign_xml.attrib.get('tag', None)
+            dns = _assign_xml.find('dns')
+            if dns and self.ra_provider:
+                do_dns = utils.xml2bool(dns.text.strip())
+                domains = [i.strip() for i in dns.attrib.get('domains', '').split() if i.strip() != '']
+            dhcp = _assign_xml.find('dhcpv6')
+            if dhcp and self.ra_provider:
+                do_dhcp = utils.xml2bool(dhcp.text.strip())
+                ra_other = utils.xml2bool(dhcp.attrib.get('advOther', 'false').strip())
+            assign = Assignment(_assign_xml,
+                                ra_dns = do_dns,
+                                ra_dhcp = do_dhcp,
+                                ra_other = ra_other,
+                                ra_tag = tag,
+                                ra_domains = domains)
             assign.alloc = self.allocations[assign.alloc_id]
             assign.parse_alloc()
             self.assignments.append(assign)
@@ -154,9 +196,13 @@ class Tunnel(object):
         self.id = int(self.xml.attrib['id'].strip())
         return(None)
 
-    def _radvd(self):
-
-        self.radvd.conf.generate(self.assignments)
+    def _ra(self):
+        # TODO: support conf path override via config XML?
+        if self.ra_provider.strip().lower() == 'dnsmasq':
+            self.ra = ra.DNSMasq()
+        elif self.ra_provider.strip().lower() == 'radvd':
+            self.ra = ra.RADVD()
+        self.ra.conf.generate(self.assignments)
         return(None)
 
     def _server(self):
@@ -171,5 +217,5 @@ class Tunnel(object):
         self._endpoint()
         self._allocations()
         self._assignments()
-        self._radvd()
+        self._ra()
         return(None)
diff --git a/utils/he_ipv6/tunnelbroker.py b/utils/he_ipv6/tunnelbroker.py
index 9d8da6d..5d34438 100644
--- a/utils/he_ipv6/tunnelbroker.py
+++ b/utils/he_ipv6/tunnelbroker.py
@@ -143,30 +143,6 @@ class TunnelBroker(object):
             ipr.close()
             raise e
         for assignment in self.tun.assignments:
-            for a in assignment.iface_addrs:
-                # The interface-specific ":1" addrs.
-                # Try to remove first in case it's already assigned.
-                try:
-                    ipr.addr('del',
-                             index = assignment.iface_idx,
-                             address = a.str,
-                             mask = a.prefix,
-                             family = socket.AF_INET6)
-                    logger.debug('Removed {0} with prefix {1} from {2}.'.format(a.str, a.prefixlen, assignment.iface))
-                except Exception as e:
-                    pass
-                try:
-                    ipr.addr('add',
-                             index = assignment.iface_idx,
-                             address = a.str,
-                             mask = a.prefix,
-                             family = socket.AF_INET6)
-                    logger.debug('Added {0} with prefix {1} to {2}.'.format(a.str, a.prefix, assignment.iface))
-                except Exception as e:
-                    logger.error(('Could not add address {0} on {1}: '
-                                  '{2}').format(a.str, assignment.iface, e))
-                    ipr.close()
-                    raise e
             # The SLAAC prefixes.
             for b in assignment.iface_blocks:
                 # Try to remove first in case it's already assigned.