run ansible upgrade playbook from undercloud

Registered by mathieu bultel

Give the possibility to an operator to be able to run upgrade playbook for the Overcloud manually from the undercloud.
The goal would be to add an option in the CLI to disable the upgrade on an existing deployment and just dump the ansible upgrade tasks in a playbook per nodes in the user $HOME or in a particular directory given by the operator.
I wrote a POC:
https://review.openstack.org/444224

Blueprint information

Status:
Complete
Approver:
Alex Schultz
Priority:
Undefined
Drafter:
mathieu bultel
Direction:
Approved
Assignee:
mathieu bultel
Definition:
Approved
Series goal:
Accepted for pike
Implementation:
Implemented
Milestone target:
None
Started by
mathieu bultel
Completed by
mathieu bultel

Related branches

Sprints

Whiteboard

A LP bug has been rise few weeks ago:
https://bugs.launchpad.net/tripleo/+bug/1665585

A POC is in progress:
https://review.openstack.org/444224

(?)

Work Items

Dependency tree

* Blueprints in grey have been implemented.

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