Open Stack

On 11/16/2017 12:06 AM, Ramu, MohanX wrote:
> Hi All,
> 
> I have a use case that I  need to apply some filter (Custom traits) 
> while Placement API fetch the resource providers for launching instance.
> 
> So that I can have list of resource provided which meets my 
> condition/filter/validation. The validation is nothing but trust about 
> the Host(compute node) where I am going to launch the instances.
> 
> The below link says that it is possible, don’t have idea how to 
> implement/test this scenario.
> 
> https://specs.openstack.org/openstack/nova-specs/specs/ocata/implemented/resource-providers-scheduler-db-filters.html
> 
> we would rather make a HTTP call to the placement API on a specific REST 
> resource with a request that would return the list of resource 
> providers’ UUIDs that would match requested resources and traits 
> criterias based on the original RequestSpec object.

Unfortunately, you're going to need to wait for this to be possible with 
the placement API. We're making progress here, but it's not complete yet.

You won't be using a custom filter (or any filter at all in the 
nova-scheduler). Rather, you'll simply have the required trait in the 
image or flavor and nova-scheduler will ask placement API for all 
providers that have the required traits and requested resource amounts.

We're probably 3-4 weeks away from having this code merged.

Best,
-jay