Trying to understand multicast packet IP routing - why src IP address affects reception ??//

[Shachar Shemesh]

I'll just point out that my Multicast understanding is a bit tenuous.

Lev Olshvang wrote:
> Evening all,
>
>
> But if I change the interface IP address to  other network, these 
> packets are ignored at IP layer  (data link layer got it since RX 
> count is running according to ifconfig )
> I have tcp ip forwarding set to 1 and application sets  multicast 
> socket option  to join the multicast group.
>
Did you change the IP address after the socket is up? Multicast needs to 
perform some handshaking before it can start sending data, and this 
handshake might be done only at the "start".

Also, I would start the debugging by running a sniffer and seeing 
whether the packets actually leave the machine, and if so, with what 
destination MAC address.

Shachar

-- 
Shachar Shemesh
Lingnu Open Source Consulting Ltd.
http://www.lingnu.com

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