Multicast route table

Andy Furniss lists at andyfurniss.entadsl.com
Wed Nov 22 19:25:09 CET 2006


Marcos Gileno wrote:
> Hi there people!
> 
> I have a linux box as a multi-homed host, 3 interfaces, and I want to 
> route a multicast traffic that comes in one of the interface to another, 
> let´s say, eth0 receveis the multicast and I want eth1 to forward it.

I guess you need a daemon like smcroute

www.cschill.de/smcroute/ was OK on 2.6s last time I tried.

I only ever did enough with multicast routing to get what I wanted 
working, so don't know all the ins and outs, but for locally generated 
traffic it seems that the interface with the mcast route will get it.

Maybe it's because I was comparing pppX and ethX rather than eths, but 
by default local generated mcast would go out on ppp0(default route 
created by pppd) which was not what I wanted, doing -

ip ro add dev br0 224.0.0.0/4

stopped it going out on ppp0 - Maybe what you see is because tcpdump 
puts ethX into promisc or something.

Andy.





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