Open Stack

One of things we have on a list of things to do during Ussuri cycle is
implementation of 'infra' images.

BP: https://blueprints.launchpad.net/kolla/+spec/infra-images

# What are infra images?

Images that are always built from binary packages (or are Java
monsters). We have about 70 such ones from quick check. All those Ceph,
Prometheus, MariaDB, cron, chrony, storm, sensu etc ones.

## libvirt image

There is 'nova-libvirt' image. Contains libvirt daemon (with qemu and
all required packages) so it would get renamed to 'libvirt'.


# Building

The idea is that 'infra' will be a new build type (like we have
'binary', 'source' etc). With all source base images marked as
unbuildable so there will be no 'debian-infra-nova-compute' one.

On the other hand building of 'binary'/'source' type images would lock
out all 'infra' ones to not get images with names like
'debian-source-ceph-mon'.


# Pros

- Clean split between OpenStack components (binary/source) and
  infrastructure needed to get them running (infra).

- Less images to publish on CI. Infra ones can be built weekly
  as they do not change much.

- No more questions how did we built ceph-mon from source ;D


# Cons

- We need to change kolla-ansible, tripleo and maybe some other
  projects' code to use new type of images.

- Migration from previous releases would be more complicated
  due to image renames.