Ho seguito la guida:

How to use install and use Iperf
Thu, 04/24/2008 - 2:30am — duntuk
Install iperf

cd /usr/local/src
wget http://internap.dl.sourceforge.net/s...f-2.0.4.tar.gz
tar xvfz iperf-2.0.4.tar.gz
cd iperf-2.0.4
./configure && make && make install

pare che abbia fatto tutto, ma se ridigito

iperf -s

mi dice ancora command not found.