This pre.yaml playbook is called as part of the openstack-fips job. Its primary purpose is enable an Ubuntu Advantage subscription using a subscription key that is stored in project-config.
Enabling FIPS requires a reboot, and so we need the FIPS playbook to run very early in the node setup, so that resources set up by subsequent pre-scripts are not affected by the reboot.
Therefore, the openstack-fips job must be definied as a base job for most OpenStack jobs. As most jobs will not require fips, a playbook variable enable_fips - which defaults to False - is provided.
To enable FIPS mode, a job will simply need to set enable_fips to True as a job variable.
Job Variables