CSM Operator

The Dell CSM Operator is a Kubernetes Operator, which can be used to install and manage the CSI Drivers and CSM Modules provided by Dell for various storage platforms. This operator is available as a community operator for upstream Kubernetes and can be deployed using OperatorHub.io. The operator can be installed using OLM (Operator Lifecycle Manager) or manually.

Supported Platforms

Dell CSM Operator has been tested and qualified on Upstream Kubernetes and OpenShift. Supported versions are listed below.

Supported CSI Drivers

Supported CSM Modules

Installation

Dell CSM Operator can be installed manually or via Operator Hub.

Manual Installation

Operator Installation on a cluster without OLM

1. Clone the Dell CSM Operator repository.
2. cd csm-operator
3. (Optional) If using a local Docker image, edit the deploy/operator.yaml file and set the image name for the CSM Operator Deployment.
4. Run bash scripts/install.sh to install the operator.

NOTE: Dell CSM Operator will be installed in the dell-csm-operator namespace.

5. Run the command kubectl get pods -n dell-csm-operator to validate the installation. If installed successfully, you should be able to see the operator pod in the dell-csm-operator namespace.

Operator Installation on a cluster with OLM

1. Clone the Dell CSM Operator repository.
2. cd csm-operator
3. Run bash scripts/install_olm.sh to install the operator.

NOTE: Dell CSM Operator will get installed in the test-csm-operator-olm namespace.

4. Once installation completes, run the command kubectl get pods -n test-csm-operator-olm to validate the installation. If installed successfully, you should be able to see the operator pods and CSV in the test-csm-operator-olm namespace. The CSV phase will be in Succeeded state.

NOTE: The recommended version of OLM for upstream Kubernetes is v0.18.2.

Installation via Operator Hub

dell-csm-operator can be installed via Operator Hub on upstream Kubernetes clusters & Red Hat OpenShift Clusters.

The installation process involves the creation of a Subscription object either via the OperatorHub UI or using kubectl/oc. While creating the Subscription you can set the Approval strategy for the InstallPlan for the operator to:

• Automatic - If you want the operator to be automatically installed or upgraded (once an upgrade is available).
• Manual - If you want a cluster administrator to manually review and approve the InstallPlan for installation/upgrades.

Uninstall

Operator uninstallation on a cluster without OLM

To uninstall a CSM operator, run bash scripts/uninstall.sh. This will uninstall the operator in dell-csm-operator namespace.

Operator uninstallation on a cluster with OLM

To uninstall a CSM operator installed with OLM run bash scripts/uninstall_olm.sh. This will uninstall the operator in test-csm-operator-olm namespace.

Custom Resource Definitions

As part of the Dell CSM Operator installation, a CRD representing configuration for the CSI Driver and CSM Modules is also installed.
containerstoragemodule CRD is installed in API Group storage.dell.com.

Drivers and modules can be installed by creating a customResource.

Custom Resource Specification

Each CSI Driver and CSM Module installation is represented by a Custom Resource.

The specification for the Custom Resource is the same for all the drivers.Below is a list of all the mandatory and optional fields in the Custom Resource specification

Mandatory fields

configVersion - Configuration version - refer here for appropriate config version.

replicas - Number of replicas for controller plugin - must be set to 1 for all drivers.

dnsPolicy - Determines the dnsPolicy for the node daemonset. Accepted values are Default, ClusterFirst, ClusterFirstWithHostNet, None.

common - This field is mandatory and is used to specify common properties for both controller and the node plugin.

• image - driver container image
• imagePullPolicy - Image Pull Policy of the driver image
• envs - List of environment variables and their values

Optional fields

controller - List of environment variables and values which are applicable only for controller.

node - List of environment variables and values which are applicable only for node.

sideCars - Specification for CSI sidecar containers.

authSecret - Name of the secret holding credentials for use by the driver. If not specified, the default secret *-creds must exist in the same namespace as driver.

tlsCertSecret - Name of the TLS cert secret for use by the driver. If not specified, a secret *-certs must exist in the namespace as driver.

tolerations - List of tolerations which should be applied to the driver StatefulSet/Deployment and DaemonSet. It should be set separately in the controller and node sections if you want separate set of tolerations for them.

nodeSelector - Used to specify node selectors for the driver StatefulSet/Deployment and DaemonSet.

Note: The image field should point to the correct image tag for version of the driver you are installing.

Pre-requisites for installation of the CSI Drivers

On Upstream Kubernetes clusters, make sure to install

• VolumeSnapshot CRDs - Install v1 VolumeSnapshot CRDs
• External Volume Snapshot Controller

Volume Snapshot CRD’s

The Kubernetes Volume Snapshot CRDs can be obtained and installed from the external-snapshotter project on Github. Manifests are available here

Volume Snapshot Controller

The CSI external-snapshotter sidecar is split into two controllers:

• A common snapshot controller
• A CSI external-snapshotter sidecar

The common snapshot controller must be installed only once in the cluster irrespective of the number of CSI drivers installed in the cluster. On OpenShift clusters, the common snapshot-controller is pre-installed. In the clusters where it is not present, it can be installed using kubectl and the manifests are available here

NOTE:

• The manifests available on GitHub install the snapshotter image:
  • quay.io/k8scsi/csi-snapshotter:v5.0.1
• The CSI external-snapshotter sidecar is still installed along with the driver and does not involve any extra configuration.

Installation example

You can install CRDs and the default snapshot controller by running the following commands:

git clone https://github.com/kubernetes-csi/external-snapshotter/
cd ./external-snapshotter
git checkout release-<your-version>
kubectl create -f client/config/crd
kubectl create -f deploy/kubernetes/snapshot-controller

NOTE:

• It is recommended to use 5.0.x version of snapshotter/snapshot-controller.

Installing CSI Driver via Operator

Refer PowerScale Driver to install the driver via Operator

Note: If you are using an OLM based installation, example manifests are available in OperatorHub UI. You can edit these manifests and install the driver using the OperatorHub UI.

Verifying the driver installation

Once the driver Custom Resource (CR) is created, you can verify the installation as mentioned below

• Check if ContainerStorageModule CR is created successfully using the command below:

  $ kubectl get csm/<name-of-custom-resource> -n <driver-namespace> -o yaml
  

• Check the status of the CR to verify if the driver installation is in the Succeeded state. If the status is not Succeeded, see the Troubleshooting guide for more information.

Update CSI Drivers

The CSI Drivers and CSM Modules installed by the Dell CSM Operator can be updated like any Kubernetes resource. This can be achieved in various ways which include:

• Modifying the installation directly via kubectl edit For e.g. - If the name of the installed PowerScale driver is powerscale, then run

  # Replace driver-namespace with the namespace where the PowerScale driver is installed
  $ kubectl edit csm/powerscale -n <driver-namespace>
  

  and modify the installation
• Modify the API object in-place via kubectl patch

Supported modifications

• Changing environment variable values for driver
• Updating the image of the driver

Uninstall CSI Driver

The CSI Drivers and CSM Modules can be uninstalled by deleting the Custom Resource.

For e.g.

$ kubectl delete csm/powerscale -n <driver-namespace>

By default, the forceRemoveDriver option is set to true which will uninstall the CSI Driver and CSM Modules when the Custom Resource is deleted. Setting this option to false is not recommended.

SideCars

Although the sidecars field in the driver specification is optional, it is strongly recommended to not modify any details related to sidecars provided (if present) in the sample manifests. The only exception to this is modifications requested by the documentation, for example, filling in blank IPs or other such system-specific data. Any modifications not specifically requested by the documentation should be only done after consulting with Dell support.

Modules

The CSM Operator can optionally enable modules that are supported by the specific Dell CSI driver. By default, the modules are disabled but they can be enabled by setting the enabled flag to true and setting any other configuration options for the given module.