Chapter 4. Creating an OpenShift Container Storage Cluster service for external mode

Procedure

1. Click Operators Installed Operators from the OpenShift Web Console to view the installed operators. Ensure that the Project selected is openshift-storage.

2. On the Installed Operators page, Click Openshift Container Storage.

   Figure 4.1. OpenShift Container Storage Operator page

   

3. On the Installed Operators Operator Details page, perform either of the following to create a Storage Cluster Service.

   1. On the Details tab Provided APIs OCS Storage Cluster, click Create Instance.

      Figure 4.2. Operator Details Page

      

   2. Alternatively, select the Storage cluster tab and click Create OCS Cluster Service.

      Figure 4.3. Storage Cluster tab

      

4. On the Create Storage Cluster page, ensure that the following options are selected:

   Figure 4.4. Connect to external cluster section on Create Storage Cluster form

   
   1. Select Mode as External. By default, Internal is selected as deployment mode.
   2. In the Connect to external cluster section, click on the Download Script link to download the python script for extracting Ceph cluster details.

   3. For extracting the Red Hat Ceph Storage (RHCS) cluster details, contact the RHCS admin to run the downloaded python script on a Red Hat Ceph Storage client node.

      • Run the following command on the RHCS client node to view the list of available arguments.

        # python3 ceph-external-cluster-details-exporter.py --help

        Important

        Use python instead of python3 if the Red Hat Ceph Storage 4.x cluster is deployed on Red Hat Enterprise Linux 7.x (RHEL 7.x) cluster.

        Note

        If you do not have access to the RHCS client node, you can also run the script from inside a MON container (containerized deployment) or from a MON node (rpm deployment).

      • To retrieve the external cluster details from the RHCS cluster, run the following command

        # python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name <rbd block pool name> [optional arguments]

        For example

        # python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name ceph-rbd --rgw-endpoint xxx.xxx.xxx.xxx:xxxx --run-as-user client.ocs

        In the above example,

        • --rbd-data-pool-name is a mandatory parameter used for providing Block Storage in OpenShift Container Storage.
        • --rgw-endpoint is optional. Provide this parameter if object storage is to be provisioned through Ceph Rados Gateway for OpenShift Container Storage.

        • -- run-as-user is an optional parameter used for providing a name for the Ceph user which is created by the script. If this parameter is not specified, a default user name client.healthchecker is created. The permissions for the new user is set as:

          • caps: [mon] allow r, allow command quorum_status

          • caps: [osd] allow rwx pool=RGW_POOL_PREFIX.rgw.meta, allow r pool=.rgw.root, allow rw pool=RGW_POOL_PREFIX.rgw.control, allow x pool=RGW_POOL_PREFIX.rgw.buckets.index

            Example of JSON output generated using the python script:

            [{"name": "rook-ceph-mon-endpoints", "kind": "ConfigMap", "data": {"data": "ceph-mon-node=xxx.xxx.xxx.xxx:xxxx", "maxMonId": "0", "mapping": "{}"}}, {"name": "rook-ceph-mon", "kind": "Secret", "data": {"admin-secret": "<admin-secret>", "cluster-name": "openshift-storage", "fsid": "<fs-id>", "mon-secret": "<mon-secret>"}}, {"name": "rook-ceph-operator-creds", "kind": "Secret", "data": {"userID": "client.healthchecker", "userKey": "<user-key>"}}, {"name": "rook-csi-rbd-node", "kind": "Secret", "data": {"userID": "csi-rbd-node", "userKey": "<user-key>"}}, {"name": "rook-csi-rbd-provisioner", "kind": "Secret", "data": {"userID": "csi-rbd-provisioner", "userKey": "<user-key>"}}, {"name": "rook-csi-cephfs-node", "kind": "Secret", "data": {"adminID": "csi-cephfs-node", "adminKey": "<admin-key>"}}, {"name": "rook-csi-cephfs-provisioner", "kind": "Secret", "data": {"adminID": "csi-cephfs-provisioner", "adminKey": "<admin-key>"}}, {"name": "ceph-rbd", "kind": "StorageClass", "data": {"pool": "ceph-rbd"}}, {"name": "cephfs", "kind": "StorageClass", "data": {"fsName": "cephfs", "pool": "cephfs_data"}}, {"name": "ceph-rgw", "kind": "StorageClass", "data": {"endpoint": "xxx.xxx.xxx.xxx:xxxx"}}]

      • Save the JSON output to a file with .json extension

        Note

        For OpenShift Container Storage to work seamlessly, ensure that the parameters (RGW endpoint, CephFS details, RBD pool, etc.) to be uploaded using the JSON file remains unchanged on the RHCS external cluster, post storage cluster creation.

   4. Click External cluster metadata Browse to select and upload the json file. The json file content will be populated and displayed in the text box.

      Figure 4.5. Json file content

      

5. Click Create.

   Note

   The Create button is enabled only after you upload the .json file.