Multicast not received by receiver.

[rakyomin78]

Hi

I have two layer3 switches, one vlan, and one routed port at 3550-1.

1. fa0/15 of 3550-2 is a routed port connecting only to one host which only know how to send broadcast.

2. 3550-1 and 3550-2 only have one vlan 10.

At fa0/15 of 3550-2:

no switchport

ip address 192.168.1.1 255.255.255.0

no shut

ip pim dense-mode

ip directed-broadcast

ip multicast help-map broadcast 239.5.5.5 mcxlate

exit

ip forward-protocol udp 65000

ip access-list extended mcxlate

10 permit udp host 192.168.1.10 any eq 65000

int vlan 10 of 3550-1

ip address 172.30.10.1 255.255.255.0

no shut

ip pim dense-mode

ip igmp join-group 239.5.5.5

int vlan 10 of 3550-2

ip address 172.30.10.2 255.255.255.0

no shut

ip pim dense-mode

ip igmp join-group 239.5.5.5

Broadcast was translated into multicast address, but multicast was not received on any vlan 10 access ports.

I captured the debug from 3550-1

*Mar 1 03:51:31.303: FIBipv4-packet-proc: route packet from Vlan1 src  192.168.1.10 dst 239.5.5.5

*Mar 1 03:5

3550-1#1:31.303: FIBfwd-proc: Default:224.0.0.0/4 multicast entry

*Mar 1 03:51:31.303: FIBipv4-packet-proc: packet routing failed

*Mar 1 03:51:31.303: FIBipv4-packet-proc: route packet from Vlan1 src  192.168.1.10 dst 239.5.5.5

*Mar 1 03:51:31.307: FIBfwd-proc: Default:224.0.0.0/4 multicast entry

*Mar 1 03:51:31.307: FIBipv4-packet-proc: packet routing failed

*Mar 1 03:51:31.623: FIBipv4-packet-proc: route packet from Vlan1 src  192.168.1.10 dst 239.5.5.5

*Mar 1 03:51:31.623: FIBfwd-proc: Default:224.0.

3550-1#0.0/4 multicast entry

*Mar 1 03:51:31.623: FIBipv4-packet-proc: packet routing failed

*Mar 1 03:51:31.623: FIBipv4-packet-proc: route packet from Vlan1 src  192.168.1.10 dst 239.5.5.5

*Mar 1 03:51:31.623: FIBfwd-proc: Default:224.0.0.0/4 multicast entry

*Mar 1 03:51:31.623: FIBipv4-packet-proc: packet routing failed

*Mar 1 03:51:31.923: FIBipv4-packet-proc: route packet from Vlan1 src  172.30.10.10 dst 79.111.108.122

*Mar 1 03:51:31.923: FIBfwd-proc: Default:0.0.0.0/0 proces level  forwarding

I  saw the src address from 192.168.1.10 and destination to 239.5.5.5 but  it was not seen on wireshark. And it said packet routing failed....  Anything which I have done wrongly?

[Lei Tian]

Hi,

Glad problem solved. Thanks for the great rating.

Cheers!

Lei Tian

[rakyomin78]

Hi Lei Tian,

I must give you good ratings because finding people who will answer a multicast question is hard and very rare. Only a handful of people answered multicast questions and most of the people I know either has no solid knowledge on mc or hated the mc completely....

[Lei Tian]

I am sure there are lot mcast experts on the forum. For me, yea, I like multicast and qos:)

Glad to help.

Lei Tian

[james-worley · Accepted solution]

Hi

Looking at your config it appear asn though there is no (S,G) entry for this group on 3550-2 and there is no incoming Interface (IIL) for the (*,G) entry. How does switch 3550-2 connect to 3550-1? Is it via a layer 2 link or a layer 3 routed port? If the two switches are conected via a routed link you will need to configure an RP address to pass the mroute data around.

I've spent a lot of time recently with multicast and found the following commands to be very helpful to me:

sh ip mroute count- This is very useful to show you RPF failures and Outgoing Interface Null (OIL) drops. This will also show you the number of received packets.

Depending on the IOS, sh mac-address-table multicast vlan x or sh mac address-table multicast vlan x- you should be able to see which port the group is forwarding on. Given you are using dense mode I would expect the switch to be flooding on all ports for that vlan. If needed I believe you can add static mac entries but i've never done it.

A quick google search for a multicast mac address calculator will help confirm you have the right address. From memory the addresses should starte 0100.5e

Do you know if your clients support IGMPv2?

[rakyomin78]

Hi JAmes,

I did a static mac address entry, and I saw multicast in wireshark of the host.

Before that no multicast was seen at all...

[james-worley · Accepted solution]

Cool - Statics, like all things, work well when you have one or two groups and/or a small network. However this soultion does not scale if you plan to be usign lots of multicast groups as the outbound flooding can fill uplinks ans swamp client NICs.

This indicated an issue with IGMP joins.

[rakyomin78]

Hi James.

Not sure why there's no multicast received by the host, I have to do a static using igmp snooping command...

[rakyomin78]

Hi James,

I got it all wrong, I should not use static at all.. I got my problem solved... Thanks.