Measure network speed on unix like OS

1. install iperf on both machines
2. Machine A run as server : iperf -s -p 65000
3. Machine B run as client : iperf -c <machine A ip> -p 65000

sample result.

[ ID] Interval       Transfer     Bandwidth

[  3]  0.0-10.0 sec    113 MBytes  94.5 Mbits/sec