IGMP Access-group

AndiS

Topology:  Source ----RP/MA----Rx----Receiver       (Sparse Dense mode)

Configure Rx so receiver can only join multicast group-1

 

Rx: ip access-list standard <ACL>

           permit <multicast group-1 >

      interface facing receiver> ip igmp access-group <ACL>

Receiver:

       int > ip igmp join <multicast group-1>

              ip igmp join <multicast group-2>               

 

Test from source:

1.  Ping multicast group-1   : should be allowed (ok).

2.  Ping multicast group-2   : should be rejected, 

     but i keep getting reply.

 

What i'm missing here ?

 

dcancerian

This configuration looks fine if you are using igmpv1 or v2 and the this ACL is applied on the router interface connecting to the receivers. you should not see multicast-group-2 entry in the output "show ip igmp group" on the router connected to the receivers.

markus.wirth

On Rx disable cef and fast switching and run...

"debug ip igmp"

"debug ip packet"

"debug ip mpacket"

 

And take a look if you can see anythin interesting. In my eyes config also should be fine.

Hint: config it the way it should work and reboot everything. Is this real gear or dynamips?

 

Regards!

Markus

markus.wirth

Do you have pim enabled on the receiver facing the Rx?

If yes...disable it because it will initiate a pim join and not a igmp request then.

Regards!

Markus

dcancerian

Do you have pim enabled on the receiver facing the Rx?

If yes...disable it because it will initiate a pim join and not a igmp request then.

PIM send a join to upstream pim neighbor only when its interface joins the igmp group, the better way to test the igmp access-group like this

SW1(f0/1)----------(f0/0)R1------Multicast network

Configure PIM on both sw1 and R1 interfaces with multicast enable on them. Apply igmp access-group on R1's f0/0. configure sw1's f0/1 to join igmp groups and check the "show ip igmp group" it should not show denied igmp group finally try to pim that deny igmp group from source.

markus.wirth

PIM send a join to upstream pim neighbor only when its interface joins the igmp group, the better way to test the igmp access-group like this

Hmm gotta read through that I think...

AndiS

Markus

You're right  Thanks !

 

Do you have pim enabled on the receiver facing the Rx?  YES

If yes...disable it because it will initiate a pim join and not a igmp request then.

 

Ping to multicast group-2 get NO reply now.

 

 

markus.wirth

Hi!

Just for details! You deactivated PIM on the Router-Interface that will get demand the multicast-group with "ip igmp join-group x.x.x.x" right? Not that we are talking about two different things. Thatll be not nice .

 

Regards!

Markus