What is iPerf / iPerf3 ? iPerf3 is a tool for active measurements of the maximum achievable bandwidth on IP networks. It supports tuning of various parameters related to timing, buffers and protocols (TCP, UDP, SCTP with IPv4 and IPv6).
New Features in iPerf 3.0 : Dynamic server (client/server parameter exchange) – Most server options from iPerf2 can now be dynamically set by the client; Client/server results exchange; A iPerf3 server accepts a single client simultaneously (multiple clients simultaneously for iPerf2)
Public iPerf3 servers. iPerf3 servers will only allow one iPerf connection at a time. Multiple tests at the same time is not supported. If a test is in progress, the following message is displayed: "iperf3: error - the server is busy running a test. try again later". …
Bug Report for iPerf3. Before submitting a bug report, try checking out the latest version of the code, and confirm that it’s not already fixed. Then submit to the iPerf3 issue tracker on GitHub: https://github.com/esnet/iperf/issues.