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CBENCH EMPTY RESULT [NOT learning destination mac addresses before the test]

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
30/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
c
Domain
cli, testing-qa

Research direction

Start by reproducing the cbench command against the POX controller on port 6633 and compare its response counters with the controller and Mininet logs shown in the issue. The payload names no source files or tests; the issue is done when the cause of the zero responses is identified and cbench produces a non-empty result in the same setup.

Written by the indexing model from the issue text.

Description

Hi,

i tried to run cbench in my pox controller as follow :

sudo cbench -c localhost -p 6633 -l 5 -M 5 -s 6
cbench: controller benchmarking tool
running in mode 'latency'
connecting to controller at localhost:6633
faking 6 switches offset 1 :: 5 tests each; 1000 ms per test
with 5 unique source MACs per switch
NOT learning destination mac addresses before the test
starting test with 0 ms delay after features_reply
ignoring first 1 "warmup" and last 0 "cooldown" loops
connection delay of 0ms per 1 switch(es)
maximum number of requests sent to controller per test is 2147483647
debugging info is off
12:29:28.357 6 switches: response/requests: 0/1 0/1 0/1 0/1 0/1 0/1 total = 0.000000 per ms
12:29:29.459 6 switches: response/requests: 0/1 0/1 0/1 0/1 0/1 0/1 total = 0.000000 per ms
12:29:30.561 6 switches: response/requests: 0/1 0/1 0/1 0/1 0/1 0/1 total = 0.000000 per ms
12:29:31.667 6 switches: response/requests: 0/1 0/1 0/1 0/1 0/1 0/1 total = 0.000000 per ms
12:29:32.767 6 switches: response/requests: 0/1 0/1 0/1 0/1 0/1 0/1 total = 0.000000 per ms
Total Count: responses/requests = 0/30
Total Average: responses/requests = 0.00/6.00
RESULT: 6 switches 4 tests min/max/avg/stdev = 0.00/0.00/0.00/0.00 responses/s

for the controller result :

sudo ./pox.py log.level --DEBUG forwarding.l2_learning
POX 0.7.0 (gar) / Copyright 2011-2020 James McCauley, et al.
DEBUG:core:POX 0.7.0 (gar) going up...
DEBUG:core:Running on CPython (3.8.5/Jan 27 2021 15:41:15)
DEBUG:core:Platform is Linux-5.8.0-53-generic-x86_64-with-glibc2.29
WARNING:version:Support for Python 3 is experimental.
INFO:core:POX 0.7.0 (gar) is up.
DEBUG:openflow.of_01:Listening on 0.0.0.0:6633
INFO:openflow.of_01:[00-00-00-00-00-01 1] connected
DEBUG:forwarding.l2_learning:Connection [00-00-00-00-00-01 1]
INFO:openflow.of_01:[00-00-00-00-00-01 2] closed
INFO:openflow.of_01:[00-00-00-00-00-02 3] closed
INFO:openflow.of_01:[00-00-00-00-00-03 4] closed
INFO:openflow.of_01:[00-00-00-00-00-04 5] closed
INFO:openflow.of_01:[00-00-00-00-00-05 6] closed
INFO:openflow.of_01:[00-00-00-00-00-06 7] closed

and for the mininet :
sudo mn --topo single,3 --mac --controller remote --switch ovsk
[sudo] password for joditanato:
*** Creating network
*** Adding controller
Unable to contact the remote controller at 127.0.0.1:6653
Connecting to remote controller at 127.0.0.1:6633
*** Adding hosts:
h1 h2 h3
*** Adding switches:
s1
*** Adding links:
(h1, s1) (h2, s1) (h3, s1)
*** Configuring hosts
h1 h2 h3
*** Starting controller
c0
*** Starting 1 switches
s1 ...
*** Starting CLI:
mininet> h1 ping h2
PING 10.0.0.2 (10.0.0.2) 56(84) bytes of data.
64 bytes from 10.0.0.2: icmp_seq=1 ttl=64 time=3.06 ms
64 bytes from 10.0.0.2: icmp_seq=2 ttl=64 time=0.231 ms
64 bytes from 10.0.0.2: icmp_seq=3 ttl=64 time=0.040 ms
64 bytes from 10.0.0.2: icmp_seq=4 ttl=64 time=0.044 ms
64 bytes from 10.0.0.2: icmp_seq=5 ttl=64 time=0.069 ms
^C
--- 10.0.0.2 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4084ms
rtt min/avg/max/mdev = 0.040/0.689/3.064/1.189 ms
mininet>

i can successfully ping from h1 to h2 but it seems like cbench can't learn destination mac address and the result is empty.
I wonder why the cbench can't learn the destination mac.

Thanks

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