03-05-2007 11:35 AM - edited 03-03-2019 04:01 PM
I have small lab network where I want to try Source Specific Multicast. Setup is very basic and according to Cisco documentation. Alas, it for some reason doesn't work. I am trying to find out why. (I am preparing for CCIE lab, by the way).
The source->receiver path is SW1-R4-R5
On R5 there is interface Loopback0, that joins group 232.0.0.1:
interface Loopback0
ip address 10.0.0.5 255.255.255.255
ip pim sparse-mode
ip igmp join-group 232.0.0.1 source 10.0.0.11
ip igmp version 3
All routers have "ip pim ssm default" in their configs; "ip pim sparse-mode" is configured on all interfaces. In fact, normal PIM SM works on the same setup fine (of course, RPs need to be added).
I try to ping 232.0.0.1 from SW1:
SW1#ping 232.0.0.1 source 10.0.0.11 repeat 4
Sending 4, 100-byte ICMP Echos to 232.0.0.1, timeout is 2 seconds:
Packet sent with a source address of 10.0.0.11
....
Doesn't work, so let's go from receiver to source:
R5#sh ip mroute 232.0.0.1
(10.0.0.11, 232.0.0.1), 02:56:25/00:02:47, flags: sLTI
Incoming interface: FastEthernet0/0, RPF nbr 10.0.3.4
Outgoing interface list:
Loopback0, Forward/Sparse, 02:56:25/00:02:47
R4#sh ip mroute 232.0.0.1
(10.0.0.11, 232.0.0.1), 03:28:55/00:02:54, flags: sT
Incoming interface: FastEthernet0/1, RPF nbr 10.0.8.11
Outgoing interface list:
FastEthernet0/0, Forward/Sparse, 02:57:00/00:02:54
SW1#sh ip mroute 232.0.0.1
(10.0.0.11, 232.0.0.1), 03:29:55/00:03:23, flags: sT
Incoming interface: Null, RPF nbr 0.0.0.0
Outgoing interface list:
Vlan2, Forward/Sparse, 02:58:01/00:03:23
This looks good, the IP addresses in "RPF nbr" fields are OK, the interfaces are OK as well.
I tried "debug ip mpacket" on R5 and R4, but that doesn't show anything, like no multicast traffic is ever flowing.
What else can I try to solve this problem? What can even go wrong with such a simple setup.
03-05-2007 11:46 AM
The "show ip mroute" outputs look good. Silly question but does R5 have a unicast route back to 10.0.0.11?
Cheers,
03-05-2007 12:09 PM
Yes, I have checked the connectivity thoroughly (or so I hope):
R5#sh ip ro 10.0.0.11
Routing entry for 10.0.0.11/32
Known via "bgp 2", distance 200, metric 0
Tag 3, type internal
Last update from 10.0.8.11 1d03h ago
Routing Descriptor Blocks:
* 10.0.8.11, from 10.0.0.4, 1d03h ago
Route metric is 0, traffic share count is 1
AS Hops 1
Route tag 3
R5#ping 10.0.0.11
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.0.0.11, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms
03-05-2007 03:54 PM
Try applying the "ip igmp join-group 232.0.0.1 source 10.0.0.11" command on R5 FastEthernet0/0 instead of loopback0.
Hope this helps,
03-06-2007 01:23 AM
That does not seem to change anything.
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