First ansible in heat
One of my first “big” commit involved the learning of config-download principles, as well as some bits of Ansible.
As of Queens (and even parts of Pike), TripleO deploy process wants to remove Puppet, prefering Ansible for the configuration deployment and management.
This means, a lot of things are to be moved and changed. Currently, TripleO calls Heat and Mistral, in order to launch processes directly from them.
Using config-download, Heat (and Mistral) will still be used, but more like some kind of “configuration repository”. They will generate ansible playbooks and configurations, and the Heat agents will then download them, and execute them on the different nodes.
My first patch in this “new” world was a simple migration from a Bash script executed by Heat to a more modern approach, using Ansible instead of Bash, and hence using the config-download process.
The patch has been merged since, but the whole process helped me understand how all of that works together, and how to test the changes.
Basically, the change hits only the [tripleo-heat-templates(https://github.com/openstack/tripleo-heat-templates) (tht/t-h-t) repository.
In order to test the changes, I had only to get a working tripleo lab - I used quickstart back then, in order to get a working undercloud with 3 controllers and a compute.
The patch will only affect the controllers, as it’s related to the public TLS certificate.
All I had to do was:
- build a new tripleo-heat-template package
- install the new package on the undercloud
- run a deploy from scratch of the overcloud
- run an update of the overcloud
Note: All the commands are executed on the undercloud, as stack user.
In order to build the package, I had to take the tripleo-ci repository:
git clone https://github.com/openstack/tripleo-ci
./tripleo-ci/scripts/tripleo.sh --delorean-setup
This will install all the requested softwares and libs in order to build proper RPMs.
All you have to do then is to clone your repository on the undercloud in the right location:
git clone https://git.openstack.org/openstack/tripleo-heat-templates ~/tripleo/tripleo-heat-templates
Do your modifications, and commit your changes.
The package build is easy, but will take some times as it runs all the configured tests. And you will just need to install the RPMs once it’s done:
./tripleo-ci/scripts/tripleo.sh --delorean-build tripleo-heat-templates
sudo yum install $(find tripleo/delorean/tripleo/delorean/data/repos/ -name "*.rpm" -and -not -name "*src.rpm")
Finally, run the deploy as usual - using quickstart you can just use the provider overcloud-deploy.sh
script.
You can also avoid package compilation: either set the --template path to the cloned version, or
symlink (ln -s the default location (/usr/share/openstack-tripleo-heat-templates).
Either way, you must run the tests before submitting your review - unless you’re happy seeing Zuul failing ;).
Happy hacking!