[Iperf] How to use iperf to measure the bandwidth betweent two computer

Bi-directional bandwidth measurement: (-r argument)

The Iperf server connects back to the client allowing the bi-directional bandwidth measurement. By default, only the bandwidth from the client to the server is measured.

If you want to measure the bi-directional bandwidth simultaneously, use the -d keyword. (See next test.)

Client side:

#iperf -c 10.1.1.1 -r

------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to 10.1.1.1, TCP port 5001
TCP window size: 16.0 KByte (default)
------------------------------------------------------------
[ 5] local 10.6.2.5 port 35726 connected with 10.1.1.1 port 5001
[ 5]   0.0-10.0 sec   1.12 MBytes   936 Kbits/sec
[ 4] local 10.6.2.5 port 5001 connected with 10.1.1.1 port 1640
[ 4]   0.0-10.1 sec   74.2 MBytes   61.7 Mbits/sec

Server side:

#iperf -s

------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
[852] local 10.1.1.1 port 5001 connected with 10.6.2.5 port 54355
[ ID]   Interval          Transfer        Bandwidth
[852]   0.0-10.1 sec   1.15 MBytes   956 Kbits/sec
------------------------------------------------------------
Client connecting to 10.6.2.5, TCP port 5001
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
[824] local 10.1.1.1 port 1646 connected with 10.6.2.5 port 5001
[ ID]   Interval          Transfer        Bandwidth
[824]   0.0-10.0 sec   73.3 MBytes   61.4 Mbits/sec


Reference:

• Iperf is a tool to measure the bandwidth and the quality of a network link.
• IPERF: How to test network Speed,Performance,Bandwidth