multicast routing woith linux.

multicast routing woith linux.

Post by » Mon, 10 Jan 2005 00:47:19


Has anyone had success running linux as a multicast router?

I am using Linux kernel 2.4.26 with multicast and multicast routing
enabled in the kernel. Additionally I have PIMSM v1 and v2 enabled as

I am using the pimd daemon from usc. I am able to configure it and
start it.
I am also using iperf to do multicast testing where I run the following
two commands to send and recive multicast packets:

To send: iperf -c -u -t 100 -i 1 -T 254
To receive: ./iperf -s -u -B -i 1

The packet do not flow through the router... I do not have iptables
loaded, and ip_forwarding is 1, rp_filter is 0.

whenever I cat /proc/net/ip_mr_cache, it shows me no entries at all!
Once in a while it does show me these entries:

-bash-2.05b# cat ip_mr_cache
Group    Origin   Iif     Pkts    Bytes    Wrong Oifs
FAFFFFEF 010010AC -1         4        0        0
373700E0 0200000A -1         4        0        0

I tried with another igmp routing daemon smcroute, which statically
enters igmp routes into the kernel. Once I do that, I get proper
entries with postive iif values for both the client and the server.
Then I am able to get igmp forwarded across the router.

It looks like pimd gets create new group request but fails to install
the route.

Can anyone help what may be the issue here, as managing each igmp route
statically is major pain!

Padam JS.