⁠6.2. Assigning Hosts to Deployment Roles

To provision RHEL OpenStack Platform using a deployment, you must assign hosts you have added to the user interface to roles in that deployment. Assigning a host to a role automatically populates configuration options for that host, such as the operating system entry, Subscription Manager details, and puppet modules to install on the host.
The following list outlines the number of hosts that must be assigned to each deployment role in accordance with the key options available when you create a deployment.

Without High Availability (Neutron)

  • One controller node.
  • One or more compute nodes.
  • One Neutron networking node.

Without High Availability (Nova)

  • One controller node.
  • One or more compute nodes.

With High Availability (Nova and Neutron)

  • Three controller nodes.
  • One or more compute nodes.

⁠6.2.1. Assigning a Host to a Deployment Role

Assign a host you have added to the user interface to one of the roles in a deployment.
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Procedure 6.4. Assigning Hosts to Deployment Roles

  1. Click OpenStack Installer → Deployments.
  2. Click the name of the deployment to which to assign hosts to open the details page for that deployment.
    ⁠
    The deployment details page

    Figure 6.6. The deployment details page

  3. In the Deployment Roles section, click + for a deployment role to display the Free Hosts section for that deployment role:
    Controller
    Provides key services such as the MySQL database for storing data about your environment, Horizon, Keystone, and Glance.
    Compute
    A host that acts as a hypervisor, providing the processing capabilities required for running virtual machines in the environment. You can add more Compute nodes to your environment at any time by assigning additional hosts to this deployment role and repeating the provisioning process; the installer ignores all hosts that have already been provisioned and provisions only the new host.
    Neutron Networking
    Provides Neutron networking services. This deployment role is only available when you select Neutron networking as the networking back end for your deployment and have selected not to use high availability.
    Ceph Storage Node (OSD)
    A generic Red Hat Enterprise Linux 7.2 host that can be manually configured after deployment to act as a Ceph storage server node. This deployment role is optional.
    Generic RHEL 7
    A generic Red Hat Enterprise Linux 7.2 host that can be manually configured after deployment to provide services not defined by any of the pre-existing deployment roles. This deployment role is optional.
  4. Select the check box for a host in the Free Hosts section.
  5. Click Assign Hosts to assign the host to the selected deployment role.

⁠6.2.2. Unassigning a Host from a Deployment

Unassign a host you have added to the user interface from one of the roles in a deployment.
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Procedure 6.5. Unassigning Hosts from Deployment Roles

  1. Click OpenStack Installer → Deployments.
  2. Click the name of the deployment from which to unassign hosts to open the details page for that deployment.
    ⁠
    The Deployment Details Page

    Figure 6.7. The Deployment Details Page

  3. In the Deployment Roles section, click the assigned hosts ( ) button for a deployment role to display the Assigned Hosts section for that deployment role.
  4. Select the check box for a host in the Assigned Hosts section.
  5. Click Unassign Hosts to unassign the host from the selected deployment role.