Adopting the {compute_service}

To adopt the {compute_service_first_ref}, you patch an existing OpenStackControlPlane custom resource (CR) where the {compute_service} is disabled. The patch starts the service with the configuration parameters that are provided by the {rhos_prev_long} ({OpenStackShort}) environment. The following procedure describes a single-cell setup.

Prerequisites

You have completed the previous adoption steps.
You have defined the following shell variables. Replace the following example values with the values that are correct for your environment:

alias openstack="oc exec -t openstackclient -- openstack"

Procedure

Patch the OpenStackControlPlane CR to deploy the {compute_service}:

oc patch openstackcontrolplane openstack -n openstack --type=merge --patch '
spec:
  nova:
    enabled: true
    apiOverride:
      route: {}
    template:
      secret: osp-secret
      apiServiceTemplate:
        override:
          service:
            internal:
              metadata:
                annotations:
                  metallb.universe.tf/address-pool: internalapi
                  metallb.universe.tf/allow-shared-ip: internalapi
                  metallb.universe.tf/loadBalancerIPs: 172.17.0.89
              spec:
                type: LoadBalancer
        customServiceConfig: |
          [workarounds]
          disable_compute_service_check_for_ffu=true
      metadataServiceTemplate:
        enabled: true # deploy single nova metadata on the top level
        override:
          service:
            metadata:
              annotations:
                metallb.universe.tf/address-pool: internalapi
                metallb.universe.tf/allow-shared-ip: internalapi
                metallb.universe.tf/loadBalancerIPs: 172.17.0.89
            spec:
              type: LoadBalancer
        customServiceConfig: |
          [workarounds]
          disable_compute_service_check_for_ffu=true
      schedulerServiceTemplate:
        customServiceConfig: |
          [workarounds]
          disable_compute_service_check_for_ffu=true
      cellTemplates:
        cell0:
          conductorServiceTemplate:
            customServiceConfig: |
              [workarounds]
              disable_compute_service_check_for_ffu=true
        cell1:
          metadataServiceTemplate:
            enabled: false # enable here to run it in a cell instead
            override:
                service:
                  metadata:
                    annotations:
                      metallb.universe.tf/address-pool: internalapi
                      metallb.universe.tf/allow-shared-ip: internalapi
                      metallb.universe.tf/loadBalancerIPs: 172.17.0.89
                  spec:
                    type: LoadBalancer
            customServiceConfig: |
              [workarounds]
              disable_compute_service_check_for_ffu=true
          conductorServiceTemplate:
            customServiceConfig: |
              [workarounds]
              disable_compute_service_check_for_ffu=true
'

The local Conductor services are started for each cell, while the superconductor runs in cell0. Note that disable_compute_service_check_for_ffu is mandatory for all imported Compute services until the external data plane is imported, and until Compute services are fast-forward upgraded. For more information, see Adopting Compute services to the {rhos_acro} data plane and Performing a fast-forward upgrade on Compute services.

Verification

Check that {compute_service} endpoints are defined and pointing to the control plane FQDNs, and that the Nova API responds:
```
openstack endpoint list | grep nova
openstack server list
```
- Compare the outputs with the topology-specific configuration in Retrieving topology-specific service configuration.
Query the superconductor to check that cell1 exists, and compare it to pre-adoption values:
```
. ~/.source_cloud_exported_variables
echo $PULL_OPENSTACK_CONFIGURATION_NOVAMANAGE_CELL_MAPPINGS
oc rsh nova-cell0-conductor-0 nova-manage cell_v2 list_cells | grep -F '| cell1 |'
```
The following changes are expected:
- The cell1 nova database and username become nova_cell1.
- The default cell is renamed to cell1.
- RabbitMQ transport URL no longer uses guest.

At this point, the {compute_service} control plane services do not control the existing {compute_service} workloads. The control plane manages the data plane only after the data adoption process is completed. For more information, see Adopting Compute services to the {rhos_acro} data plane.

To import external Compute services to the {rhos_acro} data plane, you must upgrade them first. For more information, see Adopting Compute services to the {rhos_acro} data plane, and Performing a fast-forward upgrade on Compute services.