iperf connects but does not report output

Question

I am using iperf to test network bandwidth between two Ubuntu 16.04.2 hosts (10.0.0.1 and 10.0.0.51). I ran "iperf -s" on 10.0.0.51 and then ran "iperf -c 10.0.0.51 -T 10" on 10.0.0.1. I do see the connection establishment (i.e. local 10.0.0.51 port 5001 connected with 10.0.0.1 port 37680) on both the sides but I do not get the results. It just hangs. Any help is highly appreciated. Thanks

Answer 1

with iperf3, you can see the output in json format: The command:

iperf3 -c <server-ip> -w 4000 -t 10 -i 2  -f MBytes -V -J --logfile test.log

Note: In this case make sure you can run iperf client and server same version i.e version 3 in both cases

Answer 2

Check for firewalls or packet filters, e.g. for linux use iptables -L to list them and iptables -F to delete them all. Also, what version of iperf? You might want to display interval reports (-i 1) and see what they are reporting.