Itzikr's Blog

Dell Container Storage Modules 1.8 added the support for NFS RWX volumes.

Dell PowerFlex supports all the Kubernetes PVC Access Modes:

• ReadWriteOnce – The volume can be mounted as read-write by a single node.
  
• ReadOnlyMany – The volume can be mounted as read-only by many nodes.
  
• ReadWriteMany – The volume can be mounted as read-write by many nodes.
  
• ReadWriteOncePod – The volume can be mounted as read-write by a single Pod.
  

Dell PowerFlex supports both Kubernetes Volume Modes:

• Filesystem – Kubernetes creates a filesystem on the device before mounting it for the first time.
  
• Block – Volume is presented into a Pod as a block device, without any filesystem on it.
  

In this demo we are going to integrate Dell PowerFlex 4.5 with Red Hat OpenShift 4.13 using the Dell Container Storage Modules. Then will configure ReadWriteMany PVC using both the Filesystem and Block Volume modes and ReadWriteOnce PVC using the volume mode Filesystem.

The ReadWriteMany volumes with the volume mode Filesystem will be provisioned as NFS export from a NAS Server in the PowerFlex. The ReadWriteMany volumes with volume mode Block will be provisioned as block device from the PowerFlex and mounted into the Pod as block device without any filesystem. The ReadWriteOnce volumes with the volume mode Filesystem will be provisioned as block device from the PowerFlex and a filesystem is created on the device before mounting in to the Pod as a filesystem mountpoint.

Create NAS server in the PowerFlex, this NAS Server will be used to integrate with the CSM.

Install the Dell CSM Operator from the Red Hat Operator hub, then create the PowerFlex configuration inside the OpenShift after that create PowerFlex CSM instance. This will install the SDC on to the OpenShift nodes and integrate the SDC with the PowerFlex.

Create the storage class for provisioning NFS exports.

Create RWX PVC with volume mode Filesystem.

Create Deployment to use RWX PVC, then scale the deployment to 3 replicas.

The Filesystem got created in the PowerFlex.

NFS Export got created in the PowerFlex.

We can see all the three replicas are able to write to the same RWX PVC.

Create the storage class for provisioning PowerFlex block devices with XFS filesystem.

Create RWO PVC with volume mode Filesystem.

Below, you can view a demo how it all looks