iPerf3 - SpeedTest Server on Linux CentOS 7.9 is a power tool for active measurements of the maximum achievable bandwidth on IP networks. For each test it reports the bandwidth, loss, and other parameters. It supports tuning of various parameters related to timing, buffers and protocols (TCP, UDP, SCTP with IPv4 and IPv6)

iPerf3 is very useful when you need to constantly keep an eye on bandwidth performance. Even though it is but a command line, it manages to provide powerful assistance when it comes to tweaking.

iPerf3 Features:

Client and server can have multiple simultaneous connections.

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.

Output in JSON format.

Disk read and write tests.