Metro Replication with OpenShift Virtualization

Starting in CSM 1.14, the Replication module supports the metro volume replication for Persistent Volumes (PVs) created via virtualized workloads (VMs).

OpenShift Virtualization:

  • OpenShift Virtualization allows virtual machines (VMs) to run alongside container workloads within Kubernetes clusters, addressing the coexistence of legacy VM workloads and modern containers.

OpenShift Virtualization support with Metro Replication

  • Install the OpenShift Virtualization operator from the RedHat UI on OpenShift Cluster.

  • The Replication modes supported are: Metro

  • CSI Driver supported: PowerMax, PowerStore

  • Make sure a default storage class configured for metro replication. To set the replication storage class as the default, update the annotation as follows:

    kubectl patch storageclass replication-storageclass -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'

  • Deploy a VM on the OCP cluster to provision a Persistent Volume (PV) using a data volume. The PV provisioned by the VM on the cluster will be created on the source as well as target arrays, as there is an active-active replication session between the two clusters.

  • Refer this document for creating virtual machine from the command line.

Access Metro Volume on cluster

  • Login to the VM using the virtctl binary:

    ./virtctl console <vm-name> -n <namespace>

  • Write data to Persistent Volume (PV):

      localhost:/# printf "Data written to PV" | dd  of=/dev/vda bs=1 count=150 conv=notrunc
  28+0 records in
  28+0 records out

  • Read data from Persistent Volume (PV):

      localhost:/# dd if=/dev/vda bs=1 count=150 conv=notrunc
  Data written to PV
  150+0 records in
  150+0 records out