背景信息：
自从苹果审核要求app支持ipv6的通讯以来，有很多工单咨询ipv6如何设置，今天基于Centos 6.8 64位系统搭建一下ipv6的演示环境，欢迎斧正
确认ipv6是否安装：
1.使用ifconfig命令查看网络信息是否有ipv6的信息
eth0 Link encap:Ethernet HWaddr 00:16:3E:32:A2:3E
inet addr:172.30.191.179 Bcast:172.30.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:249646 errors:0 dropped:0 overruns:0 frame:0
TX packets:21882 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:371880410 (354.6 MiB) TX bytes:1402076 (1.3 MiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:98 errors:0 dropped:0 overruns:0 frame:0
TX packets:98 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:10363 (10.1 KiB) TX bytes:10363 (10.1 KiB)2.也可以根据监听信息判断是否存在ipv6（:::123 ）的监听
# netstat -tuln
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 127.0.0.1:32000 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
udp 0 0 0.0.0.0:68 0.0.0.0:*
udp 0 0 0.0.0.0:68 0.0.0.0:*
udp 0 0 172.30.191.179:123 0.0.0.0:*
udp 0 0 127.0.0.1:123 0.0.0.0:*
udp 0 0 0.0.0.0:123 0.0.0.0:*开始搭建IPV6的工作环境
1.修改系统模块支持ipv6
# cat /etc/modprobe.d/disable_ipv6.conf
alias net-pf-10 off
options ipv6 disable=02.修改网络支持ipv6
# cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=iZ2ze24ws6xq5ug1cm4x9bZ
NETWORKING_IPV6=yes
PEERNTP=no
3.系统参数设置ipv6
# vi /etc/sysctl.conf
net.ipv6.conf.all.disable_ipv6 = 0
net.ipv6.conf.default.disable_ipv6 = 0
net.ipv6.conf.lo.disable_ipv6 = 0注：如果不重启直接sysctl -p的话会提示下面的报错，因为ipv6当前在系统内是不支持的
error: "net.ipv6.conf.all.disable_ipv6" is an unknown key
error: "net.ipv6.conf.default.disable_ipv6" is an unknown key
error: "net.ipv6.conf.lo.disable_ipv6" is an unknown key4.重启后查看ipv6的配置已经ok了
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:16:3E:32:A2:3E
inet addr:172.30.191.179 Bcast:172.30.255.255 Mask:255.255.0.0
inet6 addr: fe80::216:3eff:fe32:a23e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:670 errors:0 dropped:0 overruns:0 frame:0
TX packets:753 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:76703 (74.9 KiB) TX bytes:139326 (136.0 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:44 errors:0 dropped:0 overruns:0 frame:0
TX packets:44 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:7015 (6.8 KiB) TX bytes:7015 (6.8 KiB)HE 注册&配置&测试
1.登陆https://www.tunnelbroker.net/ 官方网站，进行账号注册，2018-04-14测试QQ邮箱可以收到注册成功的邮件了
2.登陆后点击 “Create Regular Tunnel” ，输入ECS的公网ip，出现绿底的“IP is a potential tunnel endpoint.”说明你得公网ip支持ipv6隧道,测试默认给我的节点延迟173ms，可以接受，点击页面最下方的“Create Tunnel”
3.创建ipv6隧道及路由，centos的系统选择linux-route2，返回的命令去ecs上执行
modprobe ipv6
ip tunnel add he-ipv6 mode sit remote 66.220.18.42 local 172.30.191.179 ttl 255
ip link set he-ipv6 up
ip addr add 2001:470:c:13ac::2/64 dev he-ipv6
ip route add ::/0 dev he-ipv6
ip -f inet6 addr
# ip -f inet6 addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000
inet6 fe80::216:3eff:fe32:a23e/64 scope link
valid_lft forever preferred_lft forever
4: he-ipv6: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1480
inet6 2001:470:c:13ac::2/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::276a:b88b/128 scope link
valid_lft forever preferred_lft forever
# netstat -an |grep :::
tcp 0 0 ::1:25 :::* LISTEN
udp 0 0 fe80::ac1e:bfb3:123 :::*
udp 0 0 2001:470:c:13ac::2:123 :::*
udp 0 0 fe80::216:3eff:fe32:a23e:123 :::*
udp 0 0 ::1:123 :::*
udp 0 0 :::123 :::* 
注意：如果使用了vpc的网络环境，HE上生成的命令，需要把ECS的公网ip修改成ecs内部可以看到的ip，即内网ip，可见示例配置里面note部分的提示
# ping6 ipv6.google.com
PING ipv6.google.com(tsa03s01-in-x0e.1e100.net) 56 data bytes
64 bytes from tsa03s01-in-x0e.1e100.net: icmp_seq=1 ttl=53 time=325 ms
64 bytes from tsa03s01-in-x0e.1e100.net: icmp_seq=2 ttl=53 time=325 ms
# ping6 2001:470:0:76::2
PING 2001:470:0:76::2(2001:470:0:76::2) 56 data bytes
64 bytes from 2001:470:0:76::2: icmp_seq=1 ttl=60 time=182 ms
64 bytes from 2001:470:0:76::2: icmp_seq=2 ttl=60 time=182 ms测试通过！
