Available filters in Openstack Nova-scheduler

List of Available Filters:

1.  AggregateCoreFilter: 

Filters host by number of instances with a per-aggregate max_instances_per_host value. If the per-aggregate value is not found, the value falls back to the global setting. If the host is in more than one aggregate and thus more than one value is found, the minimum value will be used.

2. AggregateRamFilter:

Filters host by RAM allocation of instances with a per-aggregate ram_allocation_ratio value. If the per-aggregate value is not found, the value falls back to the global setting. If the host is in more than one aggregate and thus more than one value is found, the minimum value will be used.

3. AggregateTypeAffinityFilter:
 Filters host by per-aggregate instance_type value.

4. AllHostsFilter:
This is a no-op filter. It does not eliminate any of the available hosts.

5. AggregateImagePropertiesIsolation:

Matches properties defined in an image's metadata against those of aggregates to determine host matches:

• If a host belongs to an aggregate and the aggregate defines one or more metadata that matches an image's properties, that host is a candidate to boot the image's instance.
• If a host does not belong to any aggregate, it can boot instances from all images

6. AvailabilityZoneFilter:

 Filters hosts by availability zone. You must enable this filter for the scheduler to respect availability zones in requests.

7. DifferentHostFilter:

Schedules the instance on a different host from a set of instances. To take advantage of this filter, the requester must pass a scheduler hint, using different_host as the key and a list of instance UUIDs as the value. This filter is the opposite of the SameHostFilter.

There are other numerous filters as well.

Weights: