You can place instances using OpenStack server groups with an affinity or anti-affinity policy. Affinity indicates that all instances in the group must placed on the same host, and anti-affinity indicates that no instances in the group can be placed on the same host.

Affinity and anti-affinity policies cannot determine the specific ESXi host on which instances are placed. These policies only control whether instances are placed on the same hosts as other instances in a server group. To place instances on specific hosts, see Use DRS to Control OpenStack Instance Placement.

Prerequisites

Verify that the intended filter configuration does not conflict with any existing administrative configuration, such as DRS rules that manage instance placement on hosts.

Procedure

  1. Log in to the VMware Integrated OpenStack dashboard as a cloud administrator.
  2. Select the admin project from the drop-down menu in the title bar.
  3. Select Project > Compute > Server Groups.
  4. Click Create Server Group and enter the desired configuration.
    Option Description
    Name

    Enter a name for the server group.
    Policy

    Select the desired policy.

    • Affinity: places instances on the same host.
    • Anti Affinity: place instances on separate hosts.
    • Soft Anti Affinity: place instances on separate hosts if possible.
    • Soft Affinity: place instances on the same host if possible.

What to do next

When you launch an instance, select the appropriate server group to implement affinity or anti-affinity.