之前移动的iptv配置是ok的。换联通之后，首先dhcp获取不到ip了，看网上的建议，
wireshark抓包，获取vender class id，dhcp能够获取ip了
然后udpxy转http，抓包能看到发出去join group的消息
root@OpenWrt:~# tcpdump -i eth1 igmp -X -n
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 262144 bytes
09:52:53.411861 IP 10.31.80.102 > 224.0.0.22: igmp v3 report, 1 group
record(s)
0x0000: 46c0 0028 0000 4000 0102 a974 0a1f 5066 F..(..@....t..Pf
0x0010: e000 0016 9404 0000 2200 e998 0000 0001 ........".......
0x0020: 0400 0000 ef00 0165 .......e
09:52:54.097849 IP 10.31.80.102 > 224.0.0.22: igmp v3 report, 1 group
record(s)
0x0000: 46c0 0028 0000 4000 0102 a974 0a1f 5066 F..(..@....t..Pf
0x0010: e000 0016 9404 0000 2200 e998 0000 0001 ........".......
0x0020: 0400 0000 ef00 0165 .......e
09:52:58.900795 IP 10.31.80.102 > 224.0.0.22: igmp v3 report, 1 group
record(s)
0x0000: 46c0 0028 0000 4000 0102 a974 0a1f 5066 F..(..@....t..Pf
0x0010: e000 0016 9404 0000 2200 ea98 0000 0001 ........".......
0x0020: 0300 0000 ef00 0165 .......e
eth1是接光猫iptv口的，光猫iptv绑定了两个接口，一个接路由器，一个接机顶盒
然后eth1设置成iptv zone，这个zone允许input/output，又单独设了允许igmp和多播地
址。当然仍然收不到回包。
-A zone_iptv_input -m comment --comment "!fw3: Custom iptv input rule chain"
-j input_iptv_rule
-A zone_iptv_input -d 224.0.0.0/4 -p udp -m comment --comment "!fw3:
allow-iptv-mcast" -j ACCEPT
-A zone_iptv_input -p igmp -m comment --comment "!fw3: allow-igmp" -j ACCEPT
-A zone_iptv_input -m conntrack --ctstate DNAT -m comment --comment "!fw3:
Accept port redirections" -j ACCEPT
-A zone_iptv_input -m comment --comment "!fw3" -j zone_iptv_src_ACCEPT
--
FROM 163.125.197.*