As deployments scale it becomes more likely that some hosts may be unreachable. They may be down for maintenance or have some temporary failure. Ideally Kolla Ansible should continue to be usable in this scenario. Controllers are more critical than compute nodes, so this issue will address unreachable compute nodes only.
Currently if one or more compute hosts are unreachable, Kolla Ansible cannot complete the deployment for all other hosts. There are several issues.
If using --limit, each host runs the setup module for itself as before. Additionally, facts are gathered for hosts outside the limit using fact delegation. Failure at this point leads to a failure of the host gathering the facts. This is an unnecessary restriction. It would be better if we could avoid this cross-host fact gathering where possible.
Fix proposed to branch: master
Review: https:/