Windows: http://linhost.info/2010/02/iperf-on-windows/

Download: http://iperf.fr/

• Command line only
• Requires an Iperf client and an Iperf server
• Server listens on port 5001 by default
  • It may be necessary to open this port on the firewall

Start the iperf server:

iperf -s

Start the iperf client and point it at the IP address of the iperf server:

iperf -c 192.168.1.70

Sample results:

------------------------------------------------------------
Client connecting to 192.168.1.70, TCP port 5001
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.0.201 port 49269 connected with 192.168.1.70 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  25.5 MBytes  21.2 Mbits/sec

Changing the iperf options will modify the parameters of the testing.

For help on options type:

iperf --help

This is an example of options that fully test a Gigabit network by changing:

• TCP window size
• Length of buffer to read or write
  • The default is 8 KB
• Using 5 parallel threads
  • The default is 1

iperf -c 192.168.1.2 -w 512k -l 512k -P 5

iperf -s -w 512k -l 512k

Sample results:

------------------------------------------------------------
Server listening on TCP port 5000
TCP window size:   256 KByte (WARNING: requested   512 KByte)
------------------------------------------------------------
[  7] local 192.168.1.2 port 5000 connected with 192.168.1.3 port 1499
[  4] local 192.168.1.2 port 5000 connected with 192.168.1.3 port 1500
[  5] local 192.168.1.2 port 5000 connected with 192.168.1.3 port 1501
[  6] local 192.168.1.2 port 5000 connected with 192.168.1.3 port 1502
[  8] local 192.168.1.2 port 5000 connected with 192.168.1.3 port 1503
[  6]  0.0-10.0 sec    221 MBytes    185 Mbits/sec
[  7]  0.0-10.0 sec    227 MBytes    190 Mbits/sec
[  8]  0.0-10.0 sec    226 MBytes    189 Mbits/sec
[  4]  0.0-10.1 sec    222 MBytes    186 Mbits/sec
[  5]  0.0-10.1 sec    225 MBytes    188 Mbits/sec
[SUM]  0.0-10.1 sec  1.10 GBytes    935 Mbits/sec

Make sure your testing client and server have Gigabit NICs (don't ask me how I know).

• UDP
• Send at 1Gbps
  • Adjust for your network
• Use 10 threads

Server:

iperf -su

Client:

iperf -c 192.168.2.50 -u -b 1G -P 10

Switch testing with Iperf