Testing

Installing docker

First, get yourself setup with docker based on our Installing docker documentation.

Software switch testing with docker

You can build and run the mininet tests with the following commands:

sudo docker build --pull -t faucet/tests -f Dockerfile.tests .
sudo apparmor_parser -R /etc/apparmor.d/usr.sbin.tcpdump
sudo modprobe openvswitch
sudo docker run --name=faucet-tests \
                --sysctl net.ipv6.conf.all.disable_ipv6=0 --privileged --rm \
                -v /var/local/lib/docker:/var/lib/docker \
                -v /tmp/faucet-pip-cache:/var/tmp/pip-cache \
                -ti faucet/tests

The apparmor command is currently required on Ubuntu hosts to allow the use of tcpdump inside the container.

If you need to use a proxy, the following to your docker run command.

--build-arg http_proxy=http://your.proxy:port

Hardware switch testing with docker

                     +--------------------------+
                     |                          |
                     |         FAUCET CPN       |
                     |                          |
                     |                          |
+------------------------------+     +-------------------------+
|                    |         |     |          |              |
|                    |    +--+ |     | +--+     |              |
|                    |    |  +---------+  |     |              |
|   FAUCET test host |    +--+ |     | +--+     |              |
|                    +--------------------------+              |
|                              |     |                         |
|                              |     |                         |
|                              |     |                         |
|                              |     |                         |
|          +---------------------+   |                         |
|          |   +------+   +--+ | |   | +--+                    |
|          |   |VM 1  |   |  +---------+  |                    |
|          |   +------+   +--+ | |   | +--+                    |
|          |                   | |   |                         |
|          |   +------+   +--+ | |   | +--+  OpenFlow switch   |
|          |   |VM 2  |   |  +---------+  |  under test        |
|          |   +------+   +--+ | |   | +--+                    |
|          |                   | |   |                         |
|          |   +------+   +--+ | |   | +--+                    |
|          |   |VM 3  |   |  +---------+  |                    |
|          |   +------+   +--+ | |   | +--+                    |
|          |                   | |   |                         |
|          |   +------+   +--+ | |   | +--+                    |
|          |   |VM 4  |   |  +---------+  |                    |
|          |   +------+   +--+ | |   | +--+                    |
|          |                   | |   |                         |
|          |                   | |   |                         |
+------------------------------+ |   +-------------------------+
           |                     |
           |    MININET          |
           |                     |
           |                     |
           +---------------------+

Requirements

Your test host, requires at least 5 interfaces. 4 interfaces to connect to the dataplane, and one for the CPN for OpenFlow. You will need to assign an IP address to the CPN interface on the host, and configure the switch with a CPN IP address and establish that they can reach each other (eg via ping).

You will need to configure the switch with two OpenFlow controllers, both with the host’s CPN IP address, but with different ports (defaults are given below for of_port and gauge_of_port).

Note

It is very important to disable any process that could cause any traffic on the dataplane test interfaces, and the test interfaces should have all IPv4/IPv6 dynamic address assignment disabled. To achieve this, on Ubuntu for example, you can set the interfaces to “unmanaged” in Network Manager, and make sure processes like Avahi ignores the test interfaces.

Note

Hardware tests must not be run from virtualized hosts (such as under VMware). The tests need to control physical port status, and need low level L2 packet access (eg. to rewrite Ethernet source and destination addresses) which virtualization may interfere with.

Note

Hardware tests require the test switch to have all non-OpenFlow switching/other features (eg. RSTP, DHCP) disabled on the dataplane test interfaces. These features will conflict with the functions FAUCET itself provides (and in turn the tests).

It is assumed that you execute all following commands from your FAUCET source code directory (eg one you have git cloned).

Test configuration

Create a directory for the test configuration:

mkdir -p /etc/faucet
$EDITOR /etc/faucet/hw_switch_config.yaml

hw_switch_config.yaml should contain the correct configuration for your switch:

hw_switch: True
hardware: 'Open vSwitch'
# Map ports on the hardware switch, to physical ports on this machine.
dp_ports:
  1: enp1s0f0
  2: enp1s0f1
  3: enp1s0f2
  4: enp1s0f3
# Hardware switch's DPID
dpid: 0xeccd6d9936ed
# Port on this machine that connects to hardware switch's CPN port.
# Hardware switch must use IP address of this port as controller IP.
cpn_intf: enp5s0
# There must be two controllers configured on the hardware switch,
# with same IP (see cpn_intf), but different ports - one for FAUCET,
# one for Gauge.
of_port: 6636
gauge_of_port: 6637
# If you wish to test OF over TLS to the hardware switch,
# set the following parameters per Ryu documentation.
# https://github.com/osrg/ryu/blob/master/doc/source/tls.rst
# ctl_privkey: ctl-privkey.pem
# ctl_cert: ctl-cert.pem
# ca_certs: /usr/local/var/lib/openvswitch/pki/switchca/cacert.pem

Running the tests

Before starting the hardware test suite for the first time, you will need to install ebtables on the host machine:

sudo apt-get install ebtables

After every reboot of your host machine you will also need to manually load the openvswitch and ebtables kernel modules. If using apparmor you will also need to disable the profile for tcpdump:

sudo modprobe openvswitch
sudo modprobe ebtables
sudo apparmor_parser -R /etc/apparmor.d/usr.sbin.tcpdump

Then you can build and run the test suite:

sudo docker build --pull -t faucet/tests -f Dockerfile.tests .
sudo docker run --name=faucet-tests \
                --privileged --rm --net=host --cap-add=NET_ADMIN \
                -v /var/local/lib/docker:/var/lib/docker \
                -v /tmp/faucet-pip-cache:/var/tmp/pip-cache \
                -v /etc/faucet:/etc/faucet \
                -v /var/tmp:/var/tmp \
                -ti faucet/tests

Test suite options

In both the software and hardware version of the test suite we can provide flags inside the FAUCET_TESTS environment variable to run specific parts of the test suite.

Note

Multiple flags can be added to FAUCET_TESTS, below are just some examples of how individual flags work.

To find the full list of options you can pass to the test suite, set FAUCET_TESTS to --help.

-e FAUCET_TESTS="--help"

Running specific integration tests

If specific test names are listed in the FAUCET_TESTS environment then only these integration tests will be run and all others skipped.

If we add the following to either of the previous docker run commands then only the FaucetUntaggedTest will be run.

-e FAUCET_TESTS="FaucetUntaggedTest"

Running only the integration tests

Sometimes you will want to skip the pytype, linting and documentation tests in order to complete a faucet test suite run against hardware quicker.

-e FAUCET_TESTS="-i"

Skip code checks

Sometimes you will want to skip the pytype, linting and documentation tests.

This can be done with with the -n flag:

-e FAUCET_TESTS="-n"

Skip unit tests

Sometimes you will want to skip the unit tests which are small tests that verify small chunks of the code base return the correct values. If these are skipped the integration tests (which spin up virtual networks and tests faucet controllers under different configurations) will still be run.

This can be done with with the -u flag:

-e FAUCET_TESTS="-u"

Checking test results

If a test fails, you can look in /var/tmp - there will be subdirectories created for each test, which will contain all the logs and debug information (including tcpdumps).

By default the test suite cleans up these files but if we use the -k flag the test suite will keep these files.

-e FAUCET_TESTS="-k"

Repeatedly running tests until failure

You can run tests until a failure is detected (eg, to diagnose an unreliable test). Tests will continue to run forever until at least one fails or the test is interrupted.

-e FAUCET_TESTS="-r"

Test debugging

Often while debugging a failed integration test it can be useful to pause the test suite at the point of the failure. The test can then be inspected live to narrow down the exact issue. To do this, run your test with the --debug flag (replace TEST_NAME with actual name of test).

-e FAUCET_TESTS="--debug TEST_NAME"

The test suite will now run in a mode where it ignores successful tests and drops into a pdb shell when a failure occurs inside a test. There are a number of different pdb commands that can be run to check the actual test code.

It is also possible to login to the virtual container environment to run interactive debug commands to inspect the state of the system.

sudo sudo docker exec -it faucet-tests /bin/bash

One useful thing can be to find the running mininet containers and execute commands inside of them, e.g ping:

[email protected]:/faucet-src# ps w | grep mininet:

  995 pts/1    Ss+    0:00 bash --norc --noediting -is mininet:faucet-637
  997 pts/2    Ss+    0:00 bash --norc --noediting -is mininet:u021
 1001 pts/3    Ss+    0:00 bash --norc --noediting -is mininet:u022
 1005 pts/4    Ss+    0:00 bash --norc --noediting -is mininet:u023
 1009 pts/5    Ss+    0:00 bash --norc --noediting -is mininet:u024
 1013 pts/6    Ss+    0:00 bash --norc --noediting -is mininet:s02
 1077 pts/7    Ss+    0:00 bash --norc --noediting -is mininet:gauge-637

[email protected]:/faucet-src# m u021 ping 127.0.0.1