igmpv3 exclude mode

[sachin30720041]

Hello,

How to configure IGMPv3 in exclude mode on XE router?

If a router does not want to receive traffic from a source then how can it mention the unwanted source address in igmp configuration ?

Thanks,

Sachin

[Flavio Miranda]

The following can be an example:

Device# configure terminal
Device(config)# interface FastEthernet 1
Device(config-if)# ip igmp version 3
Device(config-if)# ip igmp join-group 232.2.2.2 source 10.1.1.1

"If a router does not want to receive traffic from a source then how can it mention the unwanted source address in igmp configuration ?"

Well, if a source belongs to the group then it will receive traffic unless you filter it somehow:

ip access-list extended test5
deny igmp host 10.4.4.4 host 232.2.30.30
permit igmp any any
!
interface GigabitEthernet0/3/0
ip igmp access-group test5

this is an example of filter you can use.

[sachin30720041]

Hello Flavio,

R1 is the last hop router and PIM ASM is configured on R1.

R1-----Host1

When I execute 'show ip igmp groups detail' command on R1. I see one group in exclude mode and one group in include mode.

I do not know why one group is in include mode and another one is in exclude mode ?

R1# show ip igmp groups detail

Interface: GigabitEthernet0/0
Group: 224.6.6.6
Flags:
Uptime: 00:01:51
Group mode: INCLUDE
Last reporter: 100.20.30.3

Interface: GigabitEthernet0/0
Group: 224.5.5.5
Flags:
Uptime: 00:01:52
Group mode: EXCLUDE (Expires: 00:02:08)
Last reporter: 100.20.30.3
Source list is empty

R1

---------------------------
int gi0/0
ip address 100.20.30.2 255.255.255.0
no sh
ip pim sparse-mode
ip igmp version 3

Host1
------------------
int gi0/0
ip address 100.20.30.3 255.255.255.0
no sh
ip igmp version 3
ip igmp join-group 224.5.5.5
ip igmp join-group 224.6.6.6 source 6.6.6.6

Thanks,

Sachin

[Flavio Miranda]

"SSM can operate in include mode or in exclude mode. In exclude mode the receiver specifies a list of sources that it does not want to receive the multicast group traffic from. The routing device forwards traffic to the receiver from any source except the sources specified in the exclusion list. The receiver accepts traffic from any sources except the sources specified in the exclusion list."

But, in your setup:  "Source list is empty"  which means,  EXCLUDED mode gives you the possibility to filter using the list which in your case is empty.

But, for INCLUDED mode, we can´t filter.