思科路由器多播配置问题

Summer_D

采用两台电脑，两台路由器来配置多播传输。发送端电脑ip为192.168.11.2，接受端电脑ip192.168.0.2。网络拓扑结构如下图所示。采用了VLC模拟软件进行多播数据的收发。配置了路由器的sparse-dense-mode模式，多播组为224.2.127.254。配置信息如下：

router#conf t

Enter configuration commands, one perline.  End with CNTL/Z.

router(config)#ip multicast-routing

router(config)#int giga0/1

router(config-if)#ip pim sparse-dense-mode

router(config-if)#ip igmp join-group 224.2.127.254

router(config-if)#exit

router(config)#int giga0/2

router(config-if)#ip pim sparse-dense-mode

router(config-if)#end

调试信息：

Router#show ip mroute 224.2.127.254

IP Multicast Routing Table

Flags: D - Dense, S - Sparse, B - BidirGroup, s - SSM Group, C - Connected,

      L - Local, P - Pruned, R - RP-bit set, F - Register flag,

      T - SPT-bit set, J - Join SPT, M - MSDP created entry, E - Extranet,

      X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,

      U - URD, I - Received Source Specific Host Report,

      Z - Multicast Tunnel, z - MDT-data group sender,

      Y - Joined MDT-data group, y - Sending to MDT-data group,

      G - Received BGP C-Mroute, g - Sent BGP C-Mroute,

      N - Received BGP Shared-Tree Prune, n - BGP C-Mroute suppressed,

      Q - Received BGP S-A Route, q - Sent BGP S-A Route,

      V - RD & Vector, v - Vector, p - PIM Joins on route,

      x - VxLAN group

Outgoing interface flags: H - Hardwareswitched, A - Assert winner, p - PIM Join

Timers: Uptime/Expires

Interface state: Interface, Next-Hop or VCD,State/Mode

(*, 224.2.127.254), 00:06:14/stopped, RP0.0.0.0, flags: DCL

Incoming interface: Null, RPF nbr 0.0.0.0

Outgoing interface list:

   GigabitEthernet0/1, Forward/Sparse-Dense, 00:00:09/stopped

   GigabitEthernet0/2, Forward/Sparse-Dense, 00:06:14/stopped

(192.168.11.2, 224.2.127.254),00:00:09/00:02:50, flags: LT

Incoming interface: GigabitEthernet0/2, RPF nbr 10.1.0.2

Outgoing interface list:

   GigabitEthernet0/1, Forward/Sparse-Dense, 00:00:09/stopped

1---------》》》为什么这个地方的标志都是stopped？

router#show ip pim neighbor

PIM Neighbor Table

Mode: B - Bidir Capable, DR - DesignatedRouter, N - Default DR Priority,

     P - Proxy Capable, S - State Refresh Capable, G - GenID Capable

Neighbor          Interface                Uptime/Expires    Ver  DR

Address                                                            Prio/Mode

10.1.0.1          GigabitEthernet0/2       00:19:09/00:01:17 v2    1 / S P G

这个地方的neighbor是对的。

Router#show ip rpf 192.168.11.2

RPF information for ? (192.168.11.2)

  RPFinterface: GigabitEthernet0/2

  RPFneighbor: ? (10.1.0.2)

  RPFroute/mask: 192.168.11.0/24

  RPFtype: unicast (static)

Doing distance-preferred lookups across tables

  RPFtopology: ipv4 multicast base, originated from ipv4 unicast base

2---------》》》》》这个RPF中的neighbor对吗？为什么和上面的不一样？

router#show ip mroute 224.2.127.254 count

Use "show ip mfib count" to getbetter response time for a large number of mrout

es.

IP Multicast Statistics

6 routes using 3382 bytes of memory

5 groups, 0.20 average sources per group

Forwarding Counts: Pkt Count/Pkts persecond/Avg Pkt Size/Kilobits per second

Other counts: Total/RPF failed/Otherdrops(OIF-null, rate-limit etc)

Group: 224.2.127.254, Source count: 1,Packets forwarded: 32, Packets received:

32

Source: 192.168.11.2/32, Forwarding: 32/0/310/0, Other: 32/0/0

这个的信息有标明了什么？

Router#show ip mroute active

Use "show ip mfib active" to getbetter response time for a large number of mrou

tes.

Active IP Multicast Sources - sending >=4 kbps

3------》》》明明有多播路由信息，可是为什么没有活跃的多播组？

gdie2011

你这个DM-SM混合模式的我没有做过，只做过SM或者是DM模式的。你 的多播路由器之间有没运行IGP，因为多播路由器收到组播流量时要做RPF check，这个主要是靠IGP来做的，路由器会检查收到组播流量的接口是否跟到组播源的单播路由表的出接口一致，是的话，RPF check 成功，否则失败。你可以叫我qq 一起探讨，我最近也在研究组播。137270792

Summer_D

坐等大神解惑！

Summer_D

who can help me ?Come on!

Summer_D

gdie2011 发表于 2015-10-16 16:07
你这个DM-SM混合模式的我没有做过，只做过SM或者是DM模式的。你 的多播路由器之间有没运行IGP，因为多播路 ...

IGP？印象里好像只有IGMP啊。调试信息我看不太懂，已加QQ，非常感谢呐！

gdie2011

组播配置

Summer_D

按照稀疏密集模式进行配置，只需要按照上面的配置方式配置即可（去掉其中join-group那句）。收和发开始传输多播数据，这时候去查看多播路由的show ip mroute 多播地址，根据其中的信息，若是缺少incoming或outgoing接口，则只需将相应的接口加上一句ip igmp static-group 多播地址，就可以了。
一定要特别注意TTL的值，上面的拓扑图最好设置成TTL为16。
希望有类似问题的同学，可以看到。

daye