allow_resize_to_same_host=true should be the default

[Yogev Rabl]

The flag allow_resize_to_same_host in the nova.conf file is set to 'false' as default. Thus, the the command 'nova resize <instance uuid>' will fail.
The function this flag offers doesn't rise any vulnerability in the system, but gives the freedom to the user to change the flavor of an instance.

There's no logic in create a functionality just to not give it in the default configuration.

[Ray Chen (chenrano2002)]

nova reize <instance uuid> with NO flavor ID mean it's going to do migration.

so you need to anable both allow_resize_to_same_host and allow_migrate_to_same_host to True in nova.conf

[Andrew Laski (alaski)]

I have used the resize command successfully on different deployments where allow_resize_to_same_host is False. So I would be interested in what setup you're having trouble with.

The default has worked well for a number of deployments and there will need to be a strong reason for changing it.

[Liyingjun (liyingjun)]

When there is an all in one deployment, we must define allow_resize_to_same_host=True in nova.conf, if we want to resize an instance. So i think make the default value to True is useful for end user.

[OpenStack Infra (hudson-openstack)]

Change abandoned by Li Yingjun (<email address hidden>) on branch: master
Review: https://review.openstack.org/102078

[Sean Dague (sdague)]

This flag exists solely for all in one testing, and is not intended to be used on a real deployment.