iPerf3is provides an ability to measure and tune network performance. It is a cross-platform tool that can produce standardized performance measurements for any network. iPerf3 provides client and server functionality, and an ability to create data streams to measure the throughput between the two ends in one or both directions.
iPerf3 Features:

Client and server can have multiple simultaneous connections.

Can run for a specified time, rather than a set amount of data to transfer.

Run the server as a daemon.

Ignore TCP slow-start.

Set target bandwidth for UDP and TCP.

Set IPv6 flow label.

Set congestion control algorithm.

Disk read and write tests.

iPerf3 - SpeedTest Server on Ubuntu 20.04 LTS will be very useful for network administrators who need to constantly keep an eye on bandwidth performance. Even though its interface is just a command line, it provides powerful assistance when it comes to tweaking.