It is a tool to test network bandwidth between two network devices.
Step 1: Install iperf.
For Debian: # apt-get install iperf3
For Fedora/Redhat/CentOS: # yum install iperf3
Step 2: Run the command to listen on server side.
Server: # iperf3 -s
Step 3: Run the command on client side.
Client: # iperf3 -c <server IP> -l <packet size> -u -b <bandwidth>