On a older RedHat compatible server:
[root@server:/root]> iperf3 -s ----------------------------------------------------------- Server listening on 5201 -----------------------------------------------------------
On the RedHat client:
yum install iperf3 iperf3 -c server_ip
On a newer Debian server:
root@server:~# iperf -s ------------------------------------------------------------ Server listening on TCP port 5001 TCP window size: 128 KByte (default) ------------------------------------------------------------