2.6. Using the overcloud-minimal image to avoid using a Red Hat subscription entitlement

By default, director writes the QCOW2 overcloud-full image to the root disk during the provisioning process. The overcloud-full image uses a valid Red Hat subscription. However, you can also use the overcloud-minimal image, for example, to provision a bare OS where you do not want to run any other OpenStack services and consume your subscription entitlements.

A common use case for this occurs when you want to provision nodes with only Ceph daemons. For this and similar use cases, you can use the overcloud-minimal image option to avoid reaching the limit of your paid Red Hat subscriptions. For information about how to obtain the overcloud-minimal image, see Obtaining images for overcloud nodes.

注記

A Red Hat OpenStack Platform (RHOSP) subscription contains Open vSwitch (OVS), but core services, such as OVS, are not available when you use the overcloud-minimal image. OVS is not required to deploy Ceph Storage nodes. Use linux_bond instead of ovs_bond to define bonds. For more information about linux_bond, see Linux bonding options.

Procedure

  1. To configure director to use the overcloud-minimal image, create an environment file that contains the following image definition:

    parameter_defaults:
      <roleName>Image: overcloud-minimal
  2. Replace <roleName> with the name of the role and append Image to the name of the role. The following example shows an overcloud-minimal image for Ceph storage nodes:

    parameter_defaults:
      CephStorageImage: overcloud-minimal
  3. In the roles_data.yaml role definition file, set the rhsm_enforce parameter to False.

    rhsm_enforce: False
  4. Pass the environment file to the openstack overcloud deploy command.
注記

The overcloud-minimal image supports only standard Linux bridges and not OVS because OVS is an OpenStack service that requires a Red Hat OpenStack Platform subscription entitlement.