Quota exceeded when spawning instances in server group

[Slawek Kaplonski]

There is problem with quota_server_group_members.
Steps to reproduce:
1. user spawns instances in server_group and provide --min-count and --max-count parameters
2. both, min-count and max-count are below quota for instances (e.g min-count=2, max-count=5)
3. max-count is above quota_server_group_members (e.g. it was set to 3 for tenant)

In such case nova will not spawn any instance and returns error "Quota exceeded" but IMO it should spawn at least 2 instances (min-count) or 3 (quota_server_group_memebers)

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/371592

[melanie witt (melwitt)]

Note that this behavior is consistent with how multiple create currently works in general. As mentioned in this related bug [1], I think changing this behavior and making sure it's done across the board consistently is a more involved effort that should be covered in a spec.

[1] https://bugs.launchpad.net/nova/+bug/1458122

[Slawek Kaplonski (slaweq)]

I made tests of different cases when spawning instances in server group. Results of my tests are in table below:

+---------------------------------+-----------+-----------+--------------------------------+-----------------+
| QUOTAS | | | | |
+----------+----------------------+ min_count | max_count | number of spawned instances | Expected result |
|instances | server_group_members | | | | |
+==========+======================+===========+===========+================================+=================+
| 10 | 5 | 3 | 4 | 4 | 4 |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 6 | 9 |Quota exceeded, too many servers|Group Quota |
| | | | |in group (HTTP 403) |exceeded |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 3 | 6 |Quota exceeded, too many servers| 5 |
| | | | |in group (HTTP 403) | |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 3 | 11 |Quota exceeded, too many servers| 5 |
| | | | |in group (HTTP 403) | |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 6 | 11 |Quota exceeded, too many servers|Group Quota |
| | | | |in group (HTTP 403) |exceeded |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 3 | - | 3 | 3 |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 6 | - |Quota exceeded, too many servers|Group Quota |
| | | | |in group (HTTP 403) |exceeded |
+----------+----------------------+-----------+-----------+--------------------------------+-----------------+
| 10 | 5 | 11 | - |Quota exceeded for instances: |Servers Quota |
| | | | |Requested 11, but already used 0|exceeded |
| | | | | of 10 instances | |
+----------+----------------------+-----------+-----------+------------------------------...

[Slawek Kaplonski (slaweq)]

I also check how it works without server groups and behaviour also was consisten:

Spawning instances without server group:
+----------------+-----------+-----------+-----------------------------+
|quota_instances | min_count | max_count | number of spawned instances |
+================+===========+===========+=============================+
| 10 | 3 | 4 | 4 |
+----------------+-----------+-----------+-----------------------------+
| 10 | 3 | 11 | 10 |
+----------------+-----------+-----------+-----------------------------+
| 10 | 3 | - | 3 |
+----------------+-----------+-----------+-----------------------------+
| 10 | 11 | - |Quota exceeded for instances:|
| | | |Requested 11, but already |
| | | |used 0 of 10 instances |
+----------------+-----------+-----------+-----------------------------+
| 10 | - | 3 | 3 |
+----------------+-----------+-----------+-----------------------------+

[OpenStack Infra (hudson-openstack)]

Change abandoned by Slawek Kaplonski (<email address hidden>) on branch: master
Review: https://review.openstack.org/371592

[Sean Dague (sdague)]

There are no currently open reviews on this bug, changing
the status back to the previous state and unassigning. If
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