Creating and Managing Host Aggregates

Host aggregates enable administrators to assign key-value pairs to groups of machines.

Each node can have multiple aggregates and each aggregate can have multiple key-value pairs. You can assign the same key-value pair to multiple aggregates.

The scheduler uses this information to make scheduling decisions. For information, see Managing Block Storage Scheduling.

To create a host aggregate:

  1. Log in to the Dashboard.
  2. On the Admin drop-down list, select Host Aggregates.
  3. Click Create Host Aggregate.
  4. In the Create Host Aggregate dialog box, enter or select the following values on the Host Aggregate Information tab:
    • Name—The host aggregate name.
    • Availability Zone—The cloud provider defines the default availability zone, such as us-west, apac-south, or nova. You can target the host aggregate, as follows:
      • When the host aggregate is exposed as an availability zone, select the availability zone when you launch an instance.
      • When the host aggregate is not exposed as an availability zone, select a flavor and its extra specs to target the host aggregate.
  5. Assign hosts to the aggregate using the Manage Hosts within Aggregate tab in the same dialog box.
  6. To assign a host to the aggregate, click + for the host. The host moves from the All available hosts list to the Selected hosts list.
  7. Click Create Host Aggregate.

To edit host aggregates:

  1. Log in to the Dashboard.
  2. On the Admin drop-down list, select Host Aggregates.
  3. Select the host aggregate that you want to edit.
  4. Click Edit Host Aggregate in the Actions column.
  5. In the Edit Host Aggregate dialog box, change the name and availability zone for the aggregate.
  6. Click Save.

To add or remove a host aggregate:

  1. Log in to the Dashboard.
  2. On the Admin drop-down list, select Host Aggregates.
  3. Select the host aggregate that you want to edit.
  4. Select Manage Hosts from the Edit Host Aggregate drop-down list in the Actions column.
  5. In the Add/Remove Hosts to Aggregate dialog box, click + to assign a host to an aggregate. Click - to remove a host that is assigned to an aggregate.
  6. Click Save.

To delete a host aggregate:

  1. Log in to the Dashboard.
  2. On the Admin drop-down list, select Host Aggregates.
  3. Select the host aggregate that you want to delete.
  4. Click Delete Host Aggregates.
  5. Click Delete Host Aggregates on the Confirm Delete Host Aggregates dialog box.

    This action cannot be undone.