#### Instructions > [!Note] > The iperf3 tool is open source software that is available with source code and developed by [ESnet](https://www.es.net/) / [Lawrence Berkeley National Laboratory](https://www.lbl.gov/). It is released under a three-clause [BSD license](https://en.wikipedia.org/wiki/BSD_licenses). ## Download or install the iperf3 utility for the operating system (OS) being used: ### Windows Installation:  1. Download the latest Binary found [here](https://iperf.fr/iperf-download.php) 2. Extract the Binary .zip file anywhere on the local file system to later run it from. 3. There is no install for Windows, instead open a command prompt at the location the utility was extracted to. ### Red Hat Linux Installation:  1. Run the following command with superuser privileges (root): ```bash dnf install iperf3 ``` ### Ubuntu Linux Installation:  1. Run the following command with sudo privileges: ```bash sudo apt install iperf3 ``` > [!Note] > The iperf utility is installed by default on VMware ESXi 7.0 and newer located on the local file system: `/usr/lib/vmware/vsan/bin/iperf3` ## How to test available network bandwidth: 1. On the server receiving data, run the following command: ``` iperf3 -s ``` The port used (**Default 5201**) must be opened if a local firewall is enabled. You can specify a specific port If needed with the "-p <_port>_" option. 2. On the server sending data, run the following command: ``` iperf3 -c x.x.x.x ``` Replace the <x.x.x.x> with the IP address of the server from step 2.  **Figure 1:** Image of iperf3 running on Windows as server ready to receive data.    **Figure 2:** Image of iperf3 running on Linux as client showing transfer results ## Additional Information The iperf3 utility is a commonly used network testing tool that measures the throughput of a network between two systems. It allows the user to set various parameters that can be used for testing a network, or alternatively for optimizing or tuning a network. It has a client and server functionality and can measure the throughput between the two ends, either unidirectionally or bi-directionally. It is open-source software and runs on various platforms including Linux, Windows, and VMware. If a specific interface address must be used, you can specify the address to use with the "`-B <x.x.x.x>`" option. When testing networks above 10G speeds its best to connect the client with multiple threads using the "`-P <threads>`" option. > [!Note] > Additional information about iperf3 and its uses can be found at [iperf.fr](https://iperf.fr/iperf-doc.php#3doc). # Source https://www.dell.com/support/kbdoc/en-us/000139427/how-to-test-available-network-bandwidth-using-iperf