IPv4 Multicast

Everton Marques everton.marques at gmail.com
Wed May 26 13:41:52 UTC 2010


Does "show ip mroute count" on the 1841 (RP) display activity on traffic
counters?

Is the VLC sender directing multicast to the 1841 (RP) thru a default route?

Is the VLC sender issuing multicast packets with a high-enough multicast TTL
?

Everton

On Wed, May 26, 2010 at 10:21 AM, Rens <rens at autempspourmoi.be> wrote:

> I have all those things you mentioned below.
> The VLC server (10.0.1.2) sends out 2 streams on 239.255.0.1 & 239.255.0.2
> I see both in SAP, when I try to join 239.255.0.2, nothing happens in VLC
> and below you have the output of my routers & switches at that time:
>
> On my RP router I see for show ip mroute:
>
> (*, 239.255.255.255), 5d04h/00:03:26, RP 172.16.0.2, flags: SJCL
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 1d06h/00:03:26
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:41
>
> (10.0.1.2, 239.255.255.255), 1d06h/00:03:28, flags: LT
>  Incoming interface: FastEthernet0/0.200, RPF nbr 0.0.0.0
>  Outgoing interface list:
>    FastEthernet0/1, Forward/Sparse, 1d06h/00:03:26
>
> (*, 239.255.0.2), 00:01:10/00:03:19, RP 172.16.0.2, flags: S
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 00:01:10/00:03:19
>
> (*, 239.255.255.250), 00:07:19/00:03:07, RP 172.16.0.2, flags: S
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 00:07:22/00:03:03
>
> (*, 239.195.255.255), 1d06h/00:02:39, RP 172.16.0.2, flags: S
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 00:01:24/00:02:39
>
> (*, 224.2.127.254), 5d04h/00:03:10, RP 172.16.0.2, flags: SJCL
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 1d06h/00:03:10
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:38
>
> (*, 224.0.1.40), 5d04h/00:02:40, RP 172.16.0.2, flags: SJCL
>   Incoming interface: Null, RPF nbr 0.0.0.0
>  Outgoing interface list:
>     FastEthernet0/1, Forward/Sparse, 1d06h/00:02:59
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:40
>
> On my other router I have:
>
> (*, 239.255.255.255), 5d04h/stopped, RP 172.16.0.2, flags: SJCL
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:54
>
> (10.0.1.2, 239.255.255.255), 1d06h/00:02:58, flags: LJT
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 1d06h/00:02:54
>
> (*, 239.255.0.2), 00:01:55/00:02:56, RP 172.16.0.2, flags: SJC
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 00:01:55/00:02:56
>
> (*, 239.255.255.250), 00:08:04/00:02:53, RP 172.16.0.2, flags: SJC
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 00:08:04/00:02:53
>
> (*, 239.195.255.255), 5d04h/00:02:50, RP 172.16.0.2, flags: SJC
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 00:02:08/00:02:50
>
> (*, 224.2.127.254), 5d04h/00:02:48, RP 172.16.0.2, flags: SJCL
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:48
>
> (*, 224.0.1.40), 5d04h/00:02:52, RP 172.16.0.2, flags: SJCL
>  Incoming interface: FastEthernet0/1, RPF nbr 192.168.0.2
>  Outgoing interface list:
>    FastEthernet0/0.200, Forward/Sparse, 5d04h/00:02:52
>
> On the switch where the RP is connected:
>
> Vlan      Group          Version     Port List
> ---------------------------------------------------------
> 200       224.0.1.40     v2          Gi2/24
> 200       224.2.127.254  v2          Gi2/24
> 200       239.255.255.255v2          Gi2/24
>
> On the switch where the receiver is connected:
>
> Vlan      Group                    Type        Version     Port List
> -----------------------------------------------------------------------
> 200       224.0.1.40               igmp        v2          Gi0/24
> 200       224.2.127.254            igmp        v2          Gi0/1, Gi0/24
> 200       239.195.255.255          igmp        v2          Gi0/1, Gi0/24
> 200       239.255.0.2              igmp        v2          Gi0/1, Gi0/24
> 200       239.255.255.250          igmp        v2          Gi0/2, Gi0/24
> 200       239.255.255.255          igmp        v2          Gi0/1, Gi0/24
>
> -----Original Message-----
> From: Jamie Sobczyk [mailto:lanson9 at cox.net]
> Sent: vendredi 21 mai 2010 16:52
> To: rens at autempspourmoi.be
> Cc: nanog at nanog.org
> Subject: RE: IPv4 Multicast
>
> Make sure you have
> "ip multicast-routing"
> on both routers.
>
> On the router interfaces, make sure you have
> "ip pim sparse-mode"
>
> On both routers, make sure you have the same rp address assigned and
> that you can ping this ip address from both routers. (I prefer to make
> it a loopback interface)
> "ip pim rp-address w.x.y.z"
>
> Also, make sure that routing is setup on your routers so that your
> receiver can ping your sender.
>
> On your routers you should be able to see the source unicast address and
> multicast address by typing "show ip mroute"
> you should see something like this:
> (*, 239.192.3.47), 7w0d/00:02:59, RP 10.31.0.1, flags: S
>   Incoming interface: Null, RPF nbr 0.0.0.0
>   Outgoing interface list:
>     Port-channel15, Forward/Sparse, 7w0d/00:02:59, H
>
> (10.5.9.51, 239.192.3.47), 4w5d/00:03:27, flags: TA
>   Incoming interface: Port-channel15, RPF nbr 10.7.193.138
>   Outgoing interface list:
>     Port-channel17, Forward/Sparse, 4w5d/00:02:49, H
>
> On your switches, with igmp snooping enabled, you should be able to
> type:
> "show ip igmp snooping group" and see something like
> Vlan      Group                    Type        Version     Port List
> -----------------------------------------------------------------------
> 24        239.192.3.47             igmp        v2          Gi1/0/21
> That port listed is the port of the requester.
>
>
>
>
> -----Original Message-----
> I have setup a lab for this multicast.
>
> VLC receiver - 3560G - 1841 - 1841 - 4503 - VLC sender
>
> The 2 switches only provide L2 access, they have IGMP snooping active
>
> On both 1841's I have pim parse-mode & sap listen on all interfaces +
> configured a static RP, the one closest to the sender.
>
> With my VLC receiver I can see the channels via SAP, but when I join the
> multicast group I don't receive anything.
>
> Could someone help me to troubleshoot this?
>
> Thanks in advance,
>
> Rens
>
>
>
>



More information about the NANOG mailing list