Enabling user permissions to clone data volumes across namespaces

The isolating nature of namespaces means that users cannot by default clone resources between namespaces.

To enable a user to clone a virtual machine to another namespace, a user with the cluster-admin role must create a new cluster role. Bind this cluster role to a user to enable them to clone virtual machines to the destination namespace.

Prerequisites

• Only a user with the cluster-admin role can create cluster roles.

About data volumes

DataVolume objects are custom resources that are provided by the Containerized Data Importer (CDI) project. Data volumes orchestrate import, clone, and upload operations that are associated with an underlying persistent volume claim (PVC). You can create a data volume as either a standalone resource or by using the dataVolumeTemplate field in the virtual machine (VM) specification.

After a PVC is populated, the data volume that you used to create the PVC is no longer needed. OKD Virtualization enables automatic garbage collection of completed data volumes by default. Standalone data volumes, and data volumes created by using the dataVolumeTemplate resource, are automatically garbage collected after completion.

Creating RBAC resources for cloning data volumes

Create a new cluster role that enables permissions for all actions for the datavolumes resource.

Procedure

1. Create a ClusterRole manifest:

   apiVersion: rbac.authorization.k8s.io/v1
   kind: ClusterRole
   metadata:
     name: <datavolume-cloner> (1)
   rules:
   - apiGroups: ["cdi.kubevirt.io"]
     resources: ["datavolumes/source"]
     verbs: ["*"]

   1	Unique name for the cluster role.

2. Create the cluster role in the cluster:

   $ oc create -f <datavolume-cloner.yaml> (1)

   1	The file name of the ClusterRole manifest created in the previous step.

3. Create a RoleBinding manifest that applies to both the source and destination namespaces and references the cluster role created in the previous step.

   apiVersion: rbac.authorization.k8s.io/v1
   kind: RoleBinding
   metadata:
     name: <allow-clone-to-user> (1)
     namespace: <Source namespace> (2)
   subjects:
   - kind: ServiceAccount
     name: default
     namespace: <Destination namespace> (3)
   roleRef:
     kind: ClusterRole
     name: datavolume-cloner (4)
     apiGroup: rbac.authorization.k8s.io

   1	Unique name for the role binding.
   2	The namespace for the source data volume.
   3	The namespace to which the data volume is cloned.
   4	The name of the cluster role created in the previous step.

4. Create the role binding in the cluster:

   $ oc create -f <datavolume-cloner.yaml> (1)

   1	The file name of the RoleBinding manifest created in the previous step.