throw exception if no configured affinity filter

[Guangya Liu (Jay Lau)]

After https://blueprints.launchpad.net/nova/+spec/instance-group-api-extension, nova has the feature of creating instance groups with affinity or anti-affinity policy and creating vm instance with affinity/anti-affinity group.

If did not enable ServerGroupAffinityFilter and ServerGroupAntiAffinityFilter, then the instance group will not able to leverage affinity/anti-affinity.

Take the following case:
1) Create a group with affinity
2) Create two vms with this group
3) The result is that those two vms was not created on the same host.

We should throw exception if using server group with no configured affinity filter

[Gary Kotton (garyk)]

I am not sure if the filters should be enabled by default. That could be a performance hit.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/85594

[Gary Kotton (garyk)]

This was addressed by https://github.com/openstack/nova/commit/7b8402ed3ba734836119441bdf1a6d6c661c8df2

[John Garbutt (johngarbutt)]

We use milestones only at the very end of the milestone to track bugs that should block the release of the milestone. Please use tags not milestones to track bugs, try things like: my_bug_topic_milestone_name

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/85594
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=18917d9e0d6fe250cc3b4f7301d37a6c5f5faffb
Submitter: Jenkins
Branch: master

commit 18917d9e0d6fe250cc3b4f7301d37a6c5f5faffb
Author: Gary Kotton <email address hidden>
Date: Sun Apr 6 05:54:23 2014 -0700

    Scheduler: throw exception if no configured affinity filter

    If the scheduler hint indicates that the scheduling should perform
    either anti-affinity or affinity scheduling and the relevant filter
    is not configured then a NoValidHost exception will be thrown.

    This is valuable if an existing OpenStack installation is running
    and these filters are not defined after an upgrade.

    Change-Id: I79bb44ad7481b3ff924687a8d6afdd6c715c0b59
    Closes-bug: #1302238