[netperf-talk] multicast support in the "omni" tests

[Rick Jones]

Folks -

I believe I have the first, rudimentary support for IP multicast in the "omni" 
tests of netperf.

svn co http://www.netperf.org/svn/netperf2/trunk netperf2_trunk

./configure --enable_omni ...

then make and install, and start the netserver.  Then a command such as:

netperf -H <remote> -t omni -- -H <mcastaddr> -T udp -R 1 -m <messagesize>

should cause netserver to bind to the multicast address and netperf to send it 
multicast datagrams.

I still have to test setting the test to request/response and setting the 
direction so netperf receives (will require a test-specific -L <mcastaddr>) 
Feel free to try those - keeping in mind it may crash and burn.  It may also 
crash and burn if you try to do IPv6 multicast.

The -R 1 is required because by default in the top-of-trunk a unidirectional UDP 
send test sets SO_DONTROUTE to cover the backsides of people who are using 
netperf as a functional test without an airgap between them and their corporate 
network.

happy benchmarking,

rick jones