Dear all,

We're currently working hard in order to provide a nice way to run
validations within a deploy (aka in-flight validations).

We can already call validations provided by the tripleo-validations
package[1], it's working just fine.

Now comes the question: "how can we disable the validations?". In order
to do that, we propose to use a standard tag in the ansible
roles/playbooks, and to add a "--skip-tags <tag>" when we disable the
validations via the CLI or configuration.

After a quick check in the tripleoclient code, there apparently is a tag
named "validation", that can already be skipped from within the client.

So, our questions:
- would the reuse of "validation" be OK?
- if not, what tag would be best in order to avoid confusion?

We also have the idea to allow to disable validations per service. For
this, we propose to introduce the following tag:
- validation-<service>, like "validation-nova", "validation-neutron" and
so on

What do you think about those two additions?