Hi, Is therte a way to bind a server to an interface: node5> iperf -s -u -B 224.0.67.67 -i 1 ------------------------------------------------------------ Server listening on UDP port 5001 Binding to local address 224.0.67.67 Joining multicast group 224.0.67.67 Receiving 1470 byte datagrams UDP buffer size: 32.0 KByte (default) I how it can be done for the client: /usr/local/bin/iperf -c 224.0.67.67 -u --ttl 5 -t 5 -B node2 Thanks - Jacob