1. An ubuntu machine 13.10, and Mac OS X on the same LAN have no problem.
Ubuntu is using nm-0.9.8, net.ipv6.conf.wlan0.accept_ra = 2

2. This LAN is behind a Linksys EA6700 router using ISP IPv6 6rd.

3. Manual network setup (no-NM) works, i.e., no stalling to any IPv6 websites.


nmcli c down "Wired connection 1"
systemctl stop NetworkManager

ifup em1


TYPE="Ethernet"
BOOTPROTO=none
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF=yes
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
NAME="em1"
UUID="7a778ff1-fc85-46a2-914a-3cdd2ba83652"
ONBOOT="yes"
IPADDR0=192.168.1.7
PREFIX0=24
GATEWAY0=192.168.1.1
GATEWAY=192.168.1.1
DNS1=8.8.8.8
DNS2=8.8.4.4
HWADDR=12:12:12:12:12:12
IPV6ADDR=1234;1234:1234:1234::7/64
##IPV6_DEFAULTGW=fe80::1234:56ff:fe12:3456
##IPV6_DEFAULTDEV=em1

sysctl:
net.ipv6.conf.em1.accept_ra = 1
net.ipv6.conf.em1.autoconf = 1


Weirdness here, kernel RA seems to populate lots of unnecessary routes.

$ ping6 www.cisco.com
PING www.cisco.com(2600:1417:9:195::90) 56 data bytes
64 bytes from 2600:1417:9:195::90: icmp_seq=1 ttl=55 time=236 ms
64 bytes from 2600:1417:9:195::90: icmp_seq=2 ttl=55 time=228 ms
64 bytes from 2600:1417:9:195::90: icmp_seq=3 ttl=55 time=237 ms
^C
--- www.cisco.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 228.497/234.246/237.311/4.087 ms

$ ip -6 ro sh
2001:420:1101:4::a via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2001:420:1101:5::a via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2001:4860:4860::8888 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4001:c01::7d via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4003:c00::84 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:800::1010 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:801::1004 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:801::1006 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:801::100e via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:802::1018 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:803::1008 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:6800:4007:803::1017 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2404:e801:dad4:6dee::/64 dev em1  proto kernel  metric 256 
2600:1417:9:191::ad6 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2600:1417:9:195::90 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2607:f220:41e:4290::110 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2620:0:863:ed1a::1 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2620:0:863:ed1a::1:a via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2620:0:863:ed1a::2:b via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2620:114:d000:2716::200 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
2a00:1a48:7805:112:2c13:65be:ff08:2e89 via fe80::1234:56ff:fe12:3456 dev em1  metric 0 
    cache 
fe80::/64 dev em1  proto kernel  metric 256 
default via fe80::1234:56ff:fe12:3456 dev em1  proto ra  metric 1024  expires 3556sec

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