iperf3: add page (#1952)

pages/common/iperf3.md

@@ -0,0 +1,23 @@
+# iperf3
+
+> Traffic generator for testing network bandwidth.
+
+- Run iperf3 as a server:
+
+`iperf3 -s`
+
+- Run an iperf3 server on a specific port:
+
+`iperf3 -s -p{{port}}`
+
+- Start bandwidth test:
+
+`iperf3 -c{{server}}`
+
+- Run iperf3 in multiple parallel streams:
+
+`iperf3 -c{{server}} -P{{streams}}`
+
+- Reverse direction of the test. Server sends data to the client:
+
+`iperf3 -c{{server}} -R`