It would be nice to have the ability to specify the port number for the iperf3 server in Tools > Bandwidth Test.
If this is already there, this thread can be locked and/or deleted.
Iperf is not implemented.
It would be nice to have an iperf3 compatible bandwidth test tool and the ability to specify the port number for it.
there i fixed it 
+1 my vote for support iperf
Wasn’t it already requested?
[http://forum.mikrotik.com/t/feature-request-iperf/83176/1)
Why you cannot join that topic instead of creating new one?