system-config/playbooks/roles/sync-project-config/README.rst

Sync project-config to remote host

This syncs the project-config repo checked out on the bastion host (which is actually running the Ansible that runs this role) to the current host. This repo holds configuration for some production hosts and thus we want to make sure to deploy those services with the checked-out tree Zuul has prepared for a given deploy-pipeline CD job run (i.e. so we apply config updates in commit order).

Also see the setup-src to see where this checkout is setup; there are some tricks -- for example for hourly and periodic jobs we want to ensure we run from master at the time the job runs, not at the time the job was enqueued.