Enable ReadWriteOnce PVC Support in Additional Namespaces

The default general rbd-provisioner storage class is enabled for the default, kube-system, and kube-public namespaces. To enable an additional namespace, for example for an application-specific namespace, a modification to the configuration (helm overrides) of the RBD provisioner service is required.

About this task

The following example illustrates the configuration of three additional application-specific namespaces to access the RBD provisioner’s general storage class.

Note

Due to limitations with templating and merging of overrides, the entire storage class must be redefined in the override when updating specific values.

Procedure

1. List installed helm chart overrides for the platform-integ-apps.

   ~(keystone_admin)$ system helm-override-list platform-integ-apps
   +--------------------+----------------------+
   | chart name         | overrides namespaces |
   +--------------------+----------------------+
   | ceph-pools-audit   | ['kube-system']      |
   | cephfs-provisioner | ['kube-system']      |
   | rbd-provisioner    | ['kube-system']      |
   +--------------------+----------------------+
   

2. Review existing overrides for the rbd-provisioner chart. You will refer to this information in the following step.

   ~(keystone_admin)$ system helm-override-show platform-integ-apps rbd-provisioner kube-system
   +--------------------+------------------------------------------------------+
   | Property           | Value                                                |
   +--------------------+------------------------------------------------------+
   | attributes         | enabled: true                                        |
   |                    |                                                      |
   | combined_overrides | classdefaults:                                       |
   |                    |   adminId: admin                                     |
   |                    |   adminSecretName: ceph-admin                        |
   |                    |   monitors:                                          |
   |                    |   - 192.168.204.2:6789                               |
   |                    |   storageClass: general                              |
   |                    | classes:                                             |
   |                    | - additionalNamespaces:                              |
   |                    |   - default                                          |
   |                    |   - kube-public                                      |
   |                    |   chunk_size: 64                                     |
   |                    |   clusterID: 6d273112-f2a6-4aec-8727-76b690274c60    |
   |                    |   controllerExpandSecret: ceph-pool-kube-rbd         |
   |                    |   crush_rule_name: storage_tier_ruleset              |
   |                    |   name: general                                      |
   |                    |   nodeStageSecret: ceph-pool-kube-rbd                |
   |                    |   pool_name: kube-rbd                                |
   |                    |   provisionerSecret: ceph-pool-kube-rbd              |
   |                    |   replication: 1                                     |
   |                    |   userId: ceph-pool-kube-rbd                         |
   |                    |   userSecretName: ceph-pool-kube-rbd                 |
   |                    | csiConfig:                                           |
   |                    | - clusterID: 6d273112-f2a6-4aec-8727-76b690274c60    |
   |                    |   monitors:                                          |
   |                    |   - 192.168.204.2:6789                               |
   |                    | provisioner:                                         |
   |                    |   replicaCount: 1                                    |
   |                    |                                                      |
   | name               | rbd-provisioner                                      |
   | namespace          | kube-system                                          |
   | system_overrides   | classdefaults:                                       |
   |                    |   adminId: admin                                     |
   |                    |   adminSecretName: ceph-admin                        |
   |                    |   monitors: ['192.168.204.2:6789']                   |
   |                    |   storageClass: general                              |
   |                    | classes:                                             |
   |                    | - additionalNamespaces: [default, kube-public]       |
   |                    |   chunk_size: 64                                     |
   |                    |   clusterID: !!binary |                              |
   |                    |     NmQyNzMxMTItZjJhNi00YWVjLTg3MjctNzZiNjkwMjc0YzYw |
   |                    |   controllerExpandSecret: ceph-pool-kube-rbd         |
   |                    |   crush_rule_name: storage_tier_ruleset              |
   |                    |   name: general                                      |
   |                    |   nodeStageSecret: ceph-pool-kube-rbd                |
   |                    |   pool_name: kube-rbd                                |
   |                    |   provisionerSecret: ceph-pool-kube-rbd              |
   |                    |   replication: 1                                     |
   |                    |   userId: ceph-pool-kube-rbd                         |
   |                    |   userSecretName: ceph-pool-kube-rbd                 |
   |                    | csiConfig:                                           |
   |                    | - clusterID: !!binary |                              |
   |                    |     NmQyNzMxMTItZjJhNi00YWVjLTg3MjctNzZiNjkwMjc0YzYw |
   |                    |   monitors: ['192.168.204.2:6789']                   |
   |                    | provisioner: {replicaCount: 1}                       |
   |                    |                                                      |
   | user_overrides     | None                                                 |
   +--------------------+------------------------------------------------------+
   

3. Create an overrides yaml file defining the new namespaces. In this example we will create the file /home/sysadmin/update-namespaces.yaml with the following content:

           ~(keystone_admin)]$ cat <<EOF > ~/update-namespaces.yaml
   classes:
           - additionalNamespaces: [default, kube-public, new-app, new-app2, new-app3]
             chunk_size: 64
             crush_rule_name: storage_tier_ruleset
             name: general
             pool_name: kube-rbd
             replication: 2
             userId: ceph-pool-kube-rbd
             userSecretName: ceph-pool-kube-rbd
           EOF
   

4. Apply the overrides file to the chart.

   ~(keystone_admin)$ system helm-override-update  --values /home/sysadmin/update-namespaces.yaml platform-integ-apps rbd-provisioner kube-system
   +----------------+-----------------------------------------+
   | Property       | Value                                   |
   +----------------+-----------------------------------------+
   | name           | rbd-provisioner                         |
   | namespace      | kube-system                             |
   | user_overrides | classes:                                |
   |                | - additionalNamespaces:                 |
   |                |   - default                             |
   |                |   - kube-public                         |
   |                |   - new-app                             |
   |                |   - new-app2                            |
   |                |   - new-app3                            |
   |                |   chunk_size: 64                        |
   |                |   crush_rule_name: storage_tier_ruleset |
   |                |   name: general                         |
   |                |   pool_name: kube-rbd                   |
   |                |   replication: 2                        |
   |                |   userId: ceph-pool-kube-rbd            |
   |                |   userSecretName: ceph-pool-kube-rbd    |
   +----------------+-----------------------------------------+
   

5. Confirm that the new overrides have been applied to the chart.

   The following output has been edited for brevity.

   ~(keystone_admin)$ system helm-override-show platform-integ-apps rbd-provisioner kube-system
   +---------------------+--------------------------------------+
   | Property           | Value                                  |
   +--------------------+------------------------------------- --+
   | combined_overrides | ...                                    |
   |                    |                                        |
   | name               |                                        |
   | namespace          |                                        |
   | system_overrides   | ...                                    |
   |                    |                                        |
   |                    |                                        |
   | user_overrides     | classes:                               |
   |                    | - additionalNamespaces:                |
   |                    |   - default                            |
   |                    |   - kube-public                        |
   |                    |   - new-app                            |
   |                    |   - new-app2                           |
   |                    |   - new-app3                           |
   |                    |   chunk_size: 64                       |
   |                    |   crush_rule_name: storage_tier_ruleset|
   |                    |   name: general                        |
   |                    |   pool_name: kube-rbd                  |
   |                    |   replication: 2                       |
   |                    |   userId: ceph-pool-kube-rbd           |
   |                    |   userSecretName: ceph-pool-kube-rbd   |
   +--------------------+----------------------------------------+
   

6. Apply the overrides.

   1. Run the application-apply command.

      ~(keystone_admin)$ system application-apply platform-integ-apps
      +---------------+--------------------------------------+
      | Property      | Value                                |
      +---------------+--------------------------------------+
      | active        | True                                 |
      | app_version   | 1.0-62                               |
      | created_at    | 2022-12-14T04:14:08.878186+00:00     |
      | manifest_file | fluxcd-manifests                     |
      | manifest_name | platform-integ-apps-fluxcd-manifests |
      | name          | platform-integ-apps                  |
      | progress      | None                                 |
      | status        | applying                             |
      | updated_at    | 2022-12-14T04:16:33.197301+00:00     |
      +---------------+--------------------------------------+
      

   2. Monitor progress using the application-list command.

      ~(keystone_admin)$ system application-list
      +--------------------------+---------+-------------------------------------------+------------------+----------+-----------+
      | application              | version | manifest name                             | manifest file    | status   | progress  |
      +--------------------------+---------+-------------------------------------------+------------------+----------+-----------+
      | platform-integ-apps      | 1.0-62  | platform-integ-apps-fluxcd-manifests      | fluxcd-manifests | applied  | completed |
      +--------------------------+---------+-------------------------------------------+------------------+----------+-----------+
      

   You can now create and mount PVCs from the default RBD provisioner’s general storage class, from within these application-specific namespaces.

7. Apply the secret to the new rbd-provisioner namespace.

   Check if the secret has been created in the new namespace by running the following command:

   ~(keystone_admin)$ kubectl get secret ceph-pool-kube-rbd -n <namespace>
   

   If the secret has not been created in the new namespace, create it by running the following command:

   ~(keystone_admin)$ kubectl get secret ceph-pool-kube-rbd -n default -o yaml | grep -v '^\s*namespace:\s' | kubectl apply -n <namespace> -f -