---
features:
  - |
    Adds support for CentOS 8 as a host Operating System and base container
    image. This is the only major version of CentOS supported from the Ussuri
    release. The Train release supports both CentOS 7 and 8 hosts, and provides
    a route for migration.
upgrade:
  - |
    CentOS 7 is no longer supported as a host Operating System or base
    container image. CentOS users should migrate to CentOS 8. The Train release
    supports both CentOS 7 and 8 images, and provides a route for migration.
  - |
    Some images were supported by CentOS 7 but lack suitable packages in CentOS
    8, and are no longer supported for CentOS. See `Kolla release notes
    <https://docs.openstack.org/releasenotes/kolla/ussuri.html>`__ for details.
