This blog post has been updated with additional details and was originally published on 03-14-2022.

Adding storage to an OpenShift cluster can greatly increase the types of workloads you can run, including workloads such as OpenShift Virtualization, or databases such as MongoDB and PostgreSQL. Persistent volumes can be supplied in many different ways within OpenShift including using LocalVolumes, or OpenShift Data Foundation, or provided by an underlying Cloud Provider such as the vSphere provider. Storage providers for external storage arrays such as Pure CSI Driver, Dell, Infinidat CSI Driver and Synology CSI Driver also exist. While I do not have the a Pure Storage Array or an Infinibox in my home lab, I do have a Synology array, that supports iSCSI and this will be the focus of the blog. The Synology CSI driver supports the creation of ReadWriteOnce (RWO) persistent file volumes along with ReadWriteMany (RWX) persistent block volumes as well as the creation of snapshots on both these volume types.

UPDATE: An updated blog post on this topic has been written and is available here: Creating a storage network in OpenShift

Introduction

OpenShift Container Platform and OpenShift Data Foundations can supply all your data storage needs, however sometimes you want to leverage an external storage array directly using storage protocols such as NFS or iSCSI. In many cases these storage networks will be served from dedicated network segments or VLANs and use dedicated network ports or network cards to handle the traffic.