c8290ed5d0
This patch moves all specs that were implmented in the train release and set up the redirects accordingly. Change-Id: Id4b17e07f2d37cdcd789f4407b7bddd1008a23c1
179 lines
5.3 KiB
ReStructuredText
179 lines
5.3 KiB
ReStructuredText
..
|
|
This work is licensed under a Creative Commons Attribution 3.0 Unported
|
|
License.
|
|
|
|
http://creativecommons.org/licenses/by/3.0/legalcode
|
|
|
|
=================================================
|
|
Support specifying az when restore shelved server
|
|
=================================================
|
|
|
|
https://blueprints.launchpad.net/nova/+spec/support-specifying-az-when-restore-shelved-server
|
|
|
|
This blueprint proposes support admin/user to specify ``availability_zone``
|
|
to unshelve a shelved server.
|
|
|
|
Problem description
|
|
===================
|
|
If the current instance is in the ``SHELVED_OFFLOADED`` status, then its
|
|
``availability_zone`` attribute will be set to None in the ``instances``
|
|
database table (this change comes from [1]_). But the ``spec`` attribute
|
|
records the value of the AZ of the instance before being shelved in the
|
|
``request_specs`` database table. When unshelve the server, the value of
|
|
AZ will be taken from ``spec`` as 'instance.availability_zone'.
|
|
|
|
There are two ways an instance can be in an AZ::
|
|
|
|
1. The user passes an AZ on server create or
|
|
2. [DEFAULT]/default_schedule_zone is set.
|
|
|
|
For the above two cases, the RequestSpec.availability_zone will always remain
|
|
in the user-specified or [DEFAULT]/default_schedule_zone AZ, even if the AZ is
|
|
later renamed and [DEFAULT]/default_schedule_zone is changed, or that server
|
|
is on shelve/unshelve, there is a related bug here [2]_.
|
|
|
|
Once the AZ in ``spec`` is missing, unshelve server will have an error.
|
|
|
|
Use Cases
|
|
---------
|
|
As a administrator/user, I want to specify AZ when executing unshelve/restore
|
|
a shelved-offloaded server.
|
|
|
|
Proposed change
|
|
===============
|
|
Add a new microversion to the unshelve/restore shelved server
|
|
(unshelve Action) API to support specifying AZ to restore a shelved server.
|
|
|
|
If the operator configures cross_az_attach=False [3]_ in nova.conf, in the
|
|
[cinder] group, the server create flow will fail if the specified AZ does
|
|
not match the volumes being attached to the server. Unshelve should likely
|
|
also fail for the same reason, but to figure that out we'd have to iterate
|
|
the volumes (via BDMs) attached to the server and determine if their AZ
|
|
matches the user-specified AZ and if not, fail the unshelve request, and
|
|
return a badRequest(400) response, this needs to be checked as an edge case
|
|
in the API.
|
|
|
|
Add ``availability_zone`` attribute to unshelve Action request body.
|
|
|
|
The availability_zone parameter for unshelve will just be an availability zone,
|
|
not the `ZONE:HOST:NODE`_ (admin-only) format available during server create
|
|
which, when HOST and/or NODE are specified, will forcefully bypass the
|
|
scheduler.
|
|
|
|
Alternatives
|
|
------------
|
|
Creating a server from the shelved snapshot image in another AZ (or just avoid
|
|
shelve/unshelve altogether and snapshot the server, delete it, and then create
|
|
with the new AZ). The downside is you lose the ports/volumes you had connected
|
|
to the previous server.
|
|
|
|
Another alternative is the AZ rename/delete code could be changed to prevent
|
|
renaming/deleting an AZ while there are shelved offloaded servers that were
|
|
created in that AZ. This, however, would not be scalable because we'd have to
|
|
get and deserialize every RequestSpec for every ``SHELVED_OFFLOADED`` server
|
|
just to see if it had a matching AZ.
|
|
In other words, because the RequestSpec is a serialized json string in the
|
|
database, we cannot do a simple DB query to efficiently get this information.
|
|
|
|
Data model impact
|
|
-----------------
|
|
None
|
|
|
|
REST API impact
|
|
---------------
|
|
* URL:
|
|
* /v2.1/servers/{server_id}/action
|
|
|
|
* Request method:
|
|
* POST
|
|
|
|
The availability zone data will be able to add to request payload ::
|
|
|
|
{
|
|
"unshelve": {
|
|
"availability_zone": 'beijing'
|
|
}
|
|
}
|
|
|
|
The ``availability_zone`` field is optional.
|
|
|
|
If the server status is 'SHELVED' rather than 'SHELVED_OFFLOADED' and an AZ
|
|
is specified the API will return a badRequest(400) response, otherwise if my
|
|
server was created in AZ1, I shelved it (but didn't offload it yet), and then
|
|
unshelved and specified AZ2 but the server doesn't end up in AZ2, this request
|
|
will be ignored, because of that will be start instance directly. So this
|
|
change only supports the case where the server status is 'SHELVED_OFFLOADED'.
|
|
|
|
Security impact
|
|
---------------
|
|
None
|
|
|
|
Notifications impact
|
|
--------------------
|
|
None
|
|
|
|
Other end user impact
|
|
---------------------
|
|
The python-novaclient and python-openstackclient will be updated.
|
|
|
|
Performance Impact
|
|
------------------
|
|
None
|
|
|
|
Other deployer impact
|
|
---------------------
|
|
None
|
|
|
|
Developer impact
|
|
----------------
|
|
None
|
|
|
|
Upgrade impact
|
|
--------------
|
|
None
|
|
|
|
Implementation
|
|
==============
|
|
Assignee(s)
|
|
-----------
|
|
Primary assignee:
|
|
Brin Zhang
|
|
|
|
Work Items
|
|
----------
|
|
* Add a new microversion to the unshelve/restore shelved server
|
|
(unshelve Action) API
|
|
* Add related tests
|
|
|
|
Dependencies
|
|
============
|
|
None
|
|
|
|
Testing
|
|
=======
|
|
* Add related unit tests
|
|
* Add related functional tests
|
|
|
|
Documentation Impact
|
|
====================
|
|
Add docs that mention unshelve/restore shelved server after the microversion.
|
|
|
|
References
|
|
==========
|
|
|
|
.. [1] https://review.opendev.org/#/c/599087/
|
|
.. [2] https://bugs.launchpad.net/nova/+bug/1723880
|
|
|
|
.. [3] https://docs.openstack.org/nova/latest/configuration/config.html#cinder.cross_az_attach
|
|
.. _ZONE:HOST:NODE: https://docs.openstack.org/nova/latest/admin/availability-zones.html
|
|
|
|
History
|
|
=======
|
|
.. list-table:: Revisions
|
|
:header-rows: 1
|
|
|
|
* - Release Name
|
|
- Description
|
|
* - Train
|
|
- Introduced
|