[CentOS] Network throughput testing software available for CentOS/Linux

Hello everyone,

A network engineer buddy of mine brought up for discussion with me
that he'd like to do some throughput testing, but he's new to
Linux/RedHat. Is there any software I can recommend to him that
any of you find above par for CentOS 6/7?

Thanks!

Gilbert

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Gilbert Sebenste                                                    ********
(My opinions only!)                                                  ******
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