You can place instances using affinity or anti-affinity by creating a server group in OpenStack and applying desired filter as a group policy. All instances that are members of the server group will be subject to the affinity or anti-affinity policy. You can perform this configuration using the ServerGroup API from the Python nova-client.


  • Verify with the cloud administrator that your anti-affinity filter configuration does not conflict with any administrative configuration, such as DRS rules that manage instance placement on hosts.

  • Verify that you are running VMware Integrated OpenStack version 2.0.x or later.

  • Verify that VMware Integrated OpenStack is running.

  • Verify that you are using a Python nova-client version or later, as required for the ServerGroup API. Go to


  1. Create a new server group with an anti-affinity policy.
    POST /v2/TENANT_ID/os-server-groups
        "server_group": {
            "name": "SERVER_GROUP_NAME",
            "policies": ["POLICY_TYPE"]




    ID value for the OpenStack tenant.


    Specify the name for the server group.


    Specify either affinity or anti-affinity.

  2. Launch a new instance, including the os:scheduler_hints argument with the server group ID in the GET /servers command.
    ... "os:scheduler_hints": {"group": "SERVER_GROUP_UUID"}
  3. (Optional) Ask your cloud administrator to confirm that the new rule and the server group instances are created and are running correctly in the VMware Integrated OpenStack deployment in vCenter.

    The rule details appear in the Manage > Settings > VM/Host Rules page for the Compute cluster.