Kolla-G5K

Synopsis

This script deploys an OpenStack on Grid'5000 using Kolla and allows easy customization of the system (change in the default topology, configuration parameters) and reproductible experiments.

Installation

To install Kolla-G5K, first connect to the Grid'5000 frontend of your choice : and clone the repository

git clone https://github.com/BeyondTheClouds/kolla-g5k

Then install the dependencies:

cd kolla-g5k
pip install -r requirements.txt --user

Make sure to add ansible binaries to your PATH (export PATH=YOUR_HOME/.local/bin:$PATH).

Using a virtualenv is encouraged

Configuration

To deploy a full stack, you need to provide a configuration file in the YAML format. This file must include information about the Grid'5000 job and how the OpenStack services must be deployed. reservation.yaml.sample is given as an example.

# copy the sample file
cp reservation.yaml.sample reservation.yaml

#edit it with your parameters
<editor> reservation.yaml

Note on Registry backends

The deployment makes use of a private docker registry configured as a mirror of the official docker registry. There are two modes :

• ceph: false. It will start a fresh registry that will cache the images for the duration of the experiment
• ceph: true. It will use an existing Ceph rados block device of the Rennes cluster. The block device will be mounted and used as the registry storage. Setting this is usefull as the cache will persist different experiments.

The G5k ceph tutorial will guide you on how to create your rados block device.

Deploying

Then, to launch the deployment :

./kolla-g5k.py

by default the script use the file reservation.yaml as configuration file

This will run all the following phases :

• prepare-node : reserve physical machine on Grid'5000, deploys the base linux distribution, instruments nodes with the monitoring stack, installs Kolla prerequisites (runtime dependencies, input files.

• install-os : launch the Kolla deployment

• init-os : bootstrap the freshly deployed OpenStack with users, images...

Run ./kolla-g5k.py --help for a full list of command-line arguments.

After the execution, the ./current directory will contain some generated files (please note that current is a symbolic link toward the real directory associated to your deployment) and the results of the benchmarks

Launch rally benchmarks

You can launch a rally benchmark using :

./kolla-g5k.py --scenarios=<scenario file>

Ansible will connect to the node(s) hosting Rally service and launch in sequence all the benchmarks described in the scenario file.

The scenario file must resides in the rally subdirectory

Post-mortem analysis

At the end of the benchmarks, various datas (logs, influxdb, rally home directory, ...) are stored under the current directory. This enables post-mortem analysis of the experimentation.

Please refer to the result directory to know how to get started with post-mortem analysis

Example of customizations

Changing Kolla / Ansible variables

Custom Kolla / Ansible parameters can be put in the configuration file under the key kolla.

Changing the topology

Let's assume you want to run the nova-conductor in a dedicated node :

1. Add a new node reservation in the configuration file :

paravance:
  control: 1
  network: 1
  compute: 1
  conductor-node: 1

2. Create an new inventory file in the inventories subdirectory (copy paste the sample inventory) and change the group of the conductor service :

Configuration tuning

At some point, Kolla default parameters won't fit your needs. Kolla provides a mechanism to override custom section of configuration files but isn't applicable in our case (at least in the corresponding branch). So we implement a quick and dirty way of patching Kolla code to enable custom configuration files to be used (and by extension custom kolla code). See the possible patch declaration in ansible/group_vars/all.yml. Patches should be added in the configuration file of the experiment.

[nova-conductor:children]
conductor-node

3. In the configuration file, points the inventory to use to this new inventory.

4. Launch the deployment as usual, and you'll get the nova-conductor on a dedicated node.

Known limitations

• There might be an issue if your reservation contains multiple Grid'5000 clusters composed of nodes that have different network device names, e.g. paravance that has eth0 andl eth1, and parapluie that has devices eth1 and eth2.

License

This code is released under the GNU General Public License.