bash-3.2$ flent -x -H flent-fremont.bufferbloat.net -t Rich_Test --te=upload_streams=4 --socket-stats tcp_nup
Started Flent 1.3.0 using Python 2.7.15.
Starting tcp_nup test. Expected run time: 70 seconds.
WARNING: Command produced no valid data.
Runner class: SsRunner
Command: /bin/bash /usr/local/lib/python2.7/site-packages/flent/scripts/ss_iterate.sh -I 0.20 -c 300 -H localhost -t '23.239.20.41' -f ' and dport != 12865'
Return code: 0
Stdout: Time: 1567685642.N
---
Time: 1567685642.N
---
Time: 1567685642.N

... a zillion of these lines, followed by ...

Time: 1567685705.N
---
Time: 1567685706.N
---
Time: 1567685706.N
---

Stderr: /usr/local/lib/python2.7/site-packages/flent/scripts/ss_iterate.sh: line 55: ss: command not found
/usr/local/lib/python2.7/site-packages/flent/scripts/ss_iterate.sh: line 55: ss: command not found

... a zillion of these lines, and finally ...

/usr/local/lib/python2.7/site-packages/flent/scripts/ss_iterate.sh: line 55: ss: command not found

Data file written to ./tcp_nup-2019-09-05T081356.815453.Rich_Test.flent.gz.

Summary of tcp_nup test run from 2019-09-05 12:13:56.815453
  Title: 'Rich_Test'

                           avg       median          # data pts
 Ping (ms) ICMP :       100.69       101.00 ms              349
 TCP upload avg :         0.18         0.18 Mbits/s         101
 TCP upload sum :         0.31         0.30 Mbits/s         101
 TCP upload::1  :         0.15         0.13 Mbits/s           7
 TCP upload::2  :         0.23         0.21 Mbits/s          11
 TCP upload::3  :         0.17         0.17 Mbits/s           8
 TCP upload::4  :         0.23         0.21 Mbits/s          11
bash-3.2$