bash-3.2$ iperf3 -c 192.168.12.3
Connecting to host 192.168.12.3, port 5201
[  5] local 192.168.12.18 port 55737 connected to 192.168.12.3 port 5201
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  51.2 MBytes   430 Mbits/sec                 
[  5]   1.00-2.00   sec  55.4 MBytes   465 Mbits/sec                 
[  5]   2.00-3.00   sec  52.1 MBytes   438 Mbits/sec                 
[  5]   3.00-4.00   sec  45.8 MBytes   384 Mbits/sec                 
[  5]   4.00-5.00   sec  47.3 MBytes   396 Mbits/sec                 
[  5]   5.00-6.00   sec  46.1 MBytes   387 Mbits/sec                 
[  5]   6.00-7.00   sec  47.4 MBytes   398 Mbits/sec                 
[  5]   7.00-8.00   sec  57.3 MBytes   481 Mbits/sec                 
[  5]   8.00-9.00   sec  53.3 MBytes   447 Mbits/sec                 
[  5]   9.00-10.00  sec  54.9 MBytes   461 Mbits/sec                 
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.00  sec   511 MBytes   429 Mbits/sec                  sender
[  5]   0.00-10.01  sec   510 MBytes   427 Mbits/sec                  receiver
iperf Done.
bash-3.2$ iperf3 -c 192.168.12.3 -R
Connecting to host 192.168.12.3, port 5201
Reverse mode, remote host 192.168.12.3 is sending
[  5] local 192.168.12.18 port 55739 connected to 192.168.12.3 port 5201
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  52.7 MBytes   442 Mbits/sec                 
[  5]   1.00-2.00   sec  60.7 MBytes   509 Mbits/sec                 
[  5]   2.00-3.00   sec  58.2 MBytes   488 Mbits/sec                 
[  5]   3.00-4.00   sec  60.4 MBytes   507 Mbits/sec                 
[  5]   4.00-5.00   sec  58.9 MBytes   494 Mbits/sec                 
[  5]   5.00-6.00   sec  58.3 MBytes   489 Mbits/sec                 
[  5]   6.00-7.00   sec  58.6 MBytes   491 Mbits/sec                 
[  5]   7.00-8.00   sec  58.9 MBytes   494 Mbits/sec                 
[  5]   8.00-9.00   sec  59.9 MBytes   502 Mbits/sec                 
[  5]   9.00-10.00  sec  61.0 MBytes   511 Mbits/sec                 
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.01  sec   590 MBytes   495 Mbits/sec    0             sender
[  5]   0.00-10.00  sec   588 MBytes   493 Mbits/sec                  receiver