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Let's consider a user called Alice or Bob.
{{ user }} would like to start a network benchmark between the nodes of an
infrastructure. {{ user }} chooses to go with `flent <https://flent.org/>`_
and prototypes all the thing on the local machine using Vagrant.
.. literalinclude:: tutorials/ansible-integration/flent_on.py
:language: python
:linenos:
This starts {{ user }}'s experiment on the local machine using Vagrant (with
libvirt). Note that a {{ user }}'s friend will be able to run the same using
``backend="virtualbox"`` if VirtualBox is installed. Now
looking at the result directory created at the end of the execution, {{ user }}
finds:
.. image:: ./result.png
{{ user }} launches several times the script, getting new results. Subsequent
runs are faster because the machines are already up and everything is
`idempotent <https://en.wikipedia.org/wiki/Idempotence>`_.
{{ user }} now would like to go in a `real` testbed (e.g Grid'5000). Good news ! {{ user }}
only have to adapt the configuration phase and the provider used in the script.
The experimentation logic can remain the same. Thus, one can write the following:
.. literalinclude:: tutorials/ansible-integration/flent_on_grid5000.py
:language: python
:linenos:
.. image:: ./result_g5k.png
Now where {{ user }} can go from here depends on the needs:
- Moving to another provider is possible. {{ user }} only needs to learn about the specific object for
this configuration -- e.g see :ref:`[1a] <vmong5k>`, :ref:`[1b] <distem>`.
- Refactoring the code, providing a command line interface could be also nice.
After all its just python code -- see :ref:`[2] <tasks>`.
Or moving the deployment code (because it becomes large) into separated
Ansible files -- see :ref:`[3] <integration-with-ansible>`.
- Applying specific network constraints between the nodes of the reservation is
also possible. {{ user }}'ll need to learn more about how enforcing the constraints
-- see :ref:`[4] <netem>`.
- Deploying a monitoring stack can be convenient to track some system metrics. |enoslib| offers
some services that can be used easily -- see :ref:`[5] <monitoring>` or :ref:`[6] <skydive>`.