[Xorp-users] multicast problem

[Felix Engel]

On Tuesday 08 March 2005 17:16, you wrote:
> > i am trying to get multicast working. it is an easy setup with only two
> > network interfaces under gentoo linux. my application is vlc (with ttl >
> > 1). i use the bootstrap method for the rp. the "show pim join" command
> > shows the sender and the reciever. but "show pim mfc" shows not the
> > needed outgoing interface i think. does anybody konw what is wrong? i
> > have read most of the
>
> The info below shows that for source 55.66.77.2 and group 224.0.1.10
> the eth1 is the incoming interface, and eth0 is the outgoing
> interface. This seems right to me, given that your router is the RP,
> the sender is directly connected to eth1, and the receiver is on
> eth0. Why do you think the oif set is wrong?

ok. i missunderstood the output of "show pim mfc".

> Also, did the receiver get the multicast traffic?

no. in both directions the same. i can send but the receiver is getting no 
traffic. i also tried another gentoo box with the latest cvs-version of xorp. 
and another multicast-application. but the same result.

>
> > mailing-list-archive an tried all configurations that seems possible to
> > me. but i did not get the poin.
>
> BTW, there are two things in your configuration that you may want to
> fix.
>
> First, in your static routes configuration you have what seems like
> a cyclic dependency. The nexthop for the first route matches into
> the second route, and the nexthop for the second route matches into
>
> the first route:
> >         route4 55.66.77.1/24 {
> >             nexthop: 20.40.60.1
> >             metric: 1
> >         }
> >         route4 20.40.60.1/24 {
> >             nexthop: 55.66.77.1
> >             metric: 1
> >         }
>
> Given that both routes are actually the directly-connected subnets,
> you don't need them in your static routes configuration, so you can
> delete them.
>
> Second, the IP interface configuration for eth0 shows a mismatch
>
> between the IP address and the broadcast address:
> > [ 2005/03/08 15:03:52 INFO xorp_fea MFEA ] New vif: Vif[eth0] pif_index:
> > 1 vif_index: 0 addr: 20.40.60.1 subnet: 20.40.60.0/24 broadcast:
> > 192.168.1.255 peer: 0.0.0.0 Flags: MULTICAST BROADCAST UNDERLYING_VIF_UP
>
> Even though such assignment is legal, for practical purposes the
> broadcast address should be 20.40.60.255 (unless you have good
> reasons that the broadcast address should really be 192.168.1.255).

this was my fault. its from the previous test-configuration. i corrected both.

felix
>
> Regards,
> Pavlin
>
> > thanks a lot.
> > felix
> >