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Multicast forwarding on single router

9056070
Level 1
Level 1

Hi, newbie here. 

I'm trying to test/debug a custom router, now I'm working on multicast, but not sure if it's my misunderstanding or router bug(I won't surprise if it is from previous experience).  

 

The topology is fairly simple:

one router.

PC A as receiver connect to port 1, using VLC, also using wireshark checking packet.

PC B as sender connect to port 2, using iperf. (iperf -c 224.0.55.55 -u -T 5 -t 3 -i 1)

 

port1 to vlan 1, 192.168.10.0/24, PC A(.2), router(.1)

port2 to vlan 2, 192.168.1.0/24, PC B(.2), router(.1)

 

Every address is able to ping each other.

 

Router enable IGMP and PIM-SM on both vlan, using static RP 192.168.10.1

Router learn 224.0.55.55 membership from PC A, observe from Router show and wireshark.

 

But then when I try to pump multicast from B, I see nothing on A's wireshark.

 

PS.

If using IGMP snooping, and on same vlan, it will forward, but now I'm trying to clarify IGMP/PIM.

And if using dense mode, it still won't work.

This router using CLI very similar to this oracle one.

 

And below is some show information:

 

show ip igmp groups

=======================================================================
IGMP is globally enabled

I - Include Mode, E - Exclude Mode
S - Static Mbr, D - Dynamic Mbr

GroupAddress Flg Iface UpTime ExpiryTime LastReporter
--------------- --- ------- ---------------- ---------------- ---------------
224.0.55.55 D vlan1 [0d 00:00:07.21] [0d 00:04:12.22] 192.168.10.2
239.255.255.250 D vlan1 [0d 00:00:12.77] [0d 00:04:06.22] 192.168.10.2
239.255.255.250 D vlan2 [0d 00:00:10.57] [0d 00:04:08.42] 192.168.1.2

=======================================================================

 

 

show ip pim component

=======================================================================

PIM Component Information
---------------------------
Component-Id: 1
PIM Mode: sparse, PIM Version: 2
Elected BSR: 192.168.10.1
Candidate RP Holdtime: 30

=======================================================================

 

 

show ip pim rp-set

=======================================================================

PIM Group-to-RP mappings
------------------------
Group Address : 224.0.0.0 Group Mask : 255.255.0.0
RP: 192.168.10.1
Component-Id : 1
Hold Time : 150, Expiry Time : 00:02:19

=======================================================================

 

 

show ip pim mroute

=======================================================================

IP Multicast Routing Table
--------------------------
Route Flags S: SPT Bit W: Wild Card Bit R: RPT Bit
IIF State P: Pruned F: Forwarding A: Graft Ack Pending
Timers: Uptime/Expires
Interface State: Interface, State/Mode

PIM Multicast Routing Table For Component 1

Total number of Multicast Routes is 1

(*, 224.0.55.55) ,00:01:05/--- ,RP : 192.168.10.1
Incoming Interface : vlan1 ,RPF nbr : NULL ,Route Flags : WR
Outgoing InterfaceList :
vlan1, Forwarding/Sparse ,00:01:05/---

=======================================================================

4 Replies 4

Hi,

 

Are you sure that multicast packet is generated by software and received by router?

Try to debug ip pim and ip pim registration (although DR for multicast source and RP are the same device) to ensure that router gets multicast packets and does some process.

Regards,

HTH,
Please rate and mark as an accepted solution if you have found any of the information provided useful.


@Kanan Huseynli wrote:

Hi,

 

Are you sure that multicast packet is generated by software and received by router?

Try to debug ip pim and ip pim registration (although DR for multicast source and RP are the same device) to ensure that router gets multicast packets and does some process.

Regards,


From the port LED and port counter, I suppose the packet generation is ok since I said it will forward in case of same vlan and IGMP snooping.

 

Maybe I'll dive into those debug message later...just want to make sure this is all router need to config for such scenario.

 

more PS:

ip multicast is enabled

Just curious, in general, in this single router case, pim is still needed or just IGMP? 

I dont know what device do you use, but in Cisco IOS you need PIM interfaces on both interfaces.

 

 

HTH,
Please rate and mark as an accepted solution if you have found any of the information provided useful.


@Kanan Huseynli wrote:

I dont know what device do you use, but in Cisco IOS you need PIM interfaces on both interfaces.

 

 


PIM(SM)/IGMP are enabled on both interface(vlan).

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