iPerf3 Tutorial: The Ultimate Tool for Easily Evaluating Network Performance

1. Introduction to iPerf3

iPerf3 is a widely used network performance testing tool, mainly used to measure the bandwidth quality of TCP, UDP and SCTP. It is not only suitable for network administrators to detect network performance bottlenecks, but also suitable for developers to use when developing and debugging network applications. This tutorial will introduce in detail how to install, configure and use iPerf3 for network bandwidth testing.

2. Installation of iPerf3

1. Install on Linux

In most Linux distributions, iPerf3 can be installed directly through the package manager. For example, in Ubuntu or Debian systems, you can use the following command:

 sudo apt update sudo apt install iperf3

On CentOS or RHEL systems, you can use the following command:

 sudo yum install epel-release sudo yum install iperf3

2. Install on macOS

macOS users can easily install iPerf3 via Homebrew:

 brew install iperf3

3. Install on Windows

After downloading the iPerf3 installation package from the official website, unzip the file, open the cmd terminal, cd to the unzipped directory, you can find the iperf3.exe program and use it normally.

Windows users can download the iPerf3 executable file from the official GitHub repository [1], then unzip it and run it directly.

3. Basic usage of iPerf3

The use of iPerf3 requires a server and a client. The server is responsible for listening and receiving data, and the client is responsible for sending data and measuring performance.

1. Start the server

Run the following command on the server to start the iPerf3 server:

 systemctl start iperf3

This command starts the iPerf3 service. A successful startup is shown in the following figure:

2. Start the client and test

On the client, run the following command to connect to the server and perform a bandwidth test:

 iperf3 -c <服务器IP地址>

For example:

 iperf3 -c 192.168.31.102

The client will send data to the server and display the network bandwidth results. As shown in the figure below:

The results of the iPerf3 test include the following key indicators:

• Bandwidth: Network bandwidth, that is, the amount of data transmitted per second.
• Transfer: The total amount of data transferred.
• Retransmits: In TCP testing, it indicates the number of retransmitted packets.

IV. Advanced usage tips for iPerf3

1. Customize test time

By default, the iPerf3 test time is 10 seconds. You can customize the test time by using the -t option:

 iperf3 -c <服务器IP地址> -t 30

This command will measure the network bandwidth within 30 seconds. The output is shown in the figure below:

2. Test UDP bandwidth

By default, iPerf3 uses TCP for testing. To test UDP bandwidth, use the -u option:

 iperf3 -c <服务器IP地址> -u -b 10M

This command will test the bandwidth of UDP and limit the bandwidth to 10Mbps.

3. Simultaneous multi-threaded testing

iPerf3 supports multi-threaded testing. The number of threads can be specified using the -P option:

 iperf3 -c <服务器IP地址> -P 5

This command will use 5 concurrent threads for bandwidth testing.

4. Test reverse bandwidth

In some cases, you may want to test the bandwidth from the server to the client, which can be achieved with the -R option:

 iperf3 -c <服务器IP地址> -R

This command will receive data on the client side and measure the bandwidth from the server to the client.

Summarize

iPerf3 is a powerful network performance testing tool. Its easy-to-use command line interface can quickly help users evaluate network performance. Through the introduction of this article, you should have mastered how to install, configure and use iPerf3 for basic and advanced network bandwidth testing. I hope this tutorial can help you understand and use iPerf3.

Reference Documentation

[1]Official GitHub repository: https://github.com/esnet/iperf