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vSAN-like Storage for OpenShift Virtualization Engine

Replace vSAN-style local disks on OpenShift Virtualization Engine without ODF using Portworx, PowerFlex, LINSTOR, IBM Fusion, or certified CSI arrays.

vSAN-like Storage for OpenShift Virtualization Engine

Personal site note: views expressed here are my own and do not necessarily represent Red Hat or any other organization.

Most VMware exit programs that land on OpenShift Virtualization do not stall on KVM. They stall on storage. vSAN customers are used to a simple story: disks in the hosts, software replication, vMotion on a shared datastore. The first Red Hat answer they hear is often OpenShift Data Foundation (ODF). That is a good answer. It is not the only one, and it is not included with OpenShift Virtualization Engine (OVE).

This post is a solution-architect shortlist for platform and virtualization teams who want vSAN-like local-disk storage on OVE, or who already have a SAN and should not invent an HCI layer on top of it. It is not an install runbook, and it is not a support matrix. Partner listings move. Confirm the current OpenShift Virtualization storage compatibility article (KCS 7128992) and the Red Hat Ecosystem Catalog for your OpenShift version before you freeze a design.

OVE is not a storage subscription

OVE is the VM-only OpenShift SKU. Virtualization is included. ODF Essentials is not. ODF Essentials ships with OpenShift Platform Plus. You can buy ODF separately, and many teams should. You can also run partner software-defined storage as infrastructure containers that back VM disks. That pattern is explicit in the self-managed OpenShift subscription guide: storage drivers and SDS that exist to serve VMs are infrastructure, not guest applications. Confirm any borderline workload with Red Hat if it is not clearly a CSI driver or a storage control plane.

If the conversation is “we picked OVE so we would not buy ODF,” the next question is which certified CSI still gives you live migration. That is the whole problem.

What “vSAN-like” actually means here

vSAN aggregates local disks, replicates across hosts, and stays available during vMotion. OpenShift Virtualization maps that to Kubernetes CSI, not to a datastore object.

Live migration needs ReadWriteMany (RWX) so the source and destination nodes can attach the same VM disk. Prefer Block volume mode. Filesystem mode adds a guest image file on top of a filesystem on top of a volume, and it is slower for VM disks. Snapshots and clones are what make golden images, MTV imports, and crash-consistent backups cheap. Volume expansion is table stakes. Replication and DR are vendor features, not a CSI standard.

CapabilityWhy it matters for OVEvSAN analog
RWX + BlockLive migration, node drain, cluster upgradesvMotion on a shared datastore
CSI snapshots / clonesFast provision, MTV, crash-consistent backupvSAN snapshots / linked clones
Volume expansionGrow VM disks onlineDatastore / VMDK expand
Replication / DRHost failure and site recovery (vendor-specific)Failures to tolerate, stretched cluster, Site Recovery Manager

LVM Storage (LVMS / TopoLVM) and the Local Storage Operator do not clear any row in that table, by design. They bind a volume to one node (RWO) and do not replicate across hosts. Fine for a lab disk, including the Pure FlashArray + NVMe/TCP + LVMS SNO pattern. Not a vSAN replacement on a multi-node OVE cluster. If the PVC is RWO, live migration is blocked and the VM powers off on drain.

Three architectures, not thirty products

Red Hat’s storage considerations for OpenShift Virtualization cuts the problem into three models. Pick the model first. Then pick a vendor.

ModelWhere the disks liveWhen to use it
Internal SDS (HCI or partial)Local NVMe/SSD on OVE nodesTrue vSAN analog; no array; platform team owns storage
External CSI (SAN / NAS)PowerFlex, FlashSystem, ONTAP, Alletra, FlashArray, VSPYou already have an array; storage team keeps the data plane
Shared-disk file systemOne large LUN + IBM Fusion Access or Arctera InfoscaleOlder SAN without a mature RWX CSI; typically up to roughly 40 nodes

HCI SDS is the vSAN operating model: disks in the hypervisor hosts, software pool, CSI on top. External CSI is the FC/iSCSI/NVMe-oF datastore model you already run next to vSAN. Shared-disk file systems exist for arrays whose CSI is not VM-grade yet.

Do not drop ODF or Portworx on top of a SAN that already has a working RWX CSI. That is an extra license, extra latency, and write amplification from a second replication layer. Use it only when the array CSI cannot do RWX, snapshots, clones, or small-LUN-per-VM-disk provisioning.

HCI / local-disk SDS: the vSAN shortlist

These products consume disks in the OVE nodes (or a storage-node subset) and present RWX block through CSI. No external array required.

ProductPartnerTopologyOVE virt fitNotes
Portworx EnterpriseEverpure (Pure lineage)HCI on local SCSI/NVMe; also FlashArray or other arraysCertified, including local diskMost common vSAN stand-in. Same product can later front a FlashArray if you leave HCI.
Dell PowerFlexDellHCI rack/appliance or two-layer SDSCertified via Dell CSMNVMe/TCP or PowerFlex protocol. Natural if the account already runs Dell SDS.
LINSTOR + DRBDLINBITReplicated local block on OVE nodesCertified for OpenShift VirtualizationLightest analog to vSAN FTT. Live migration, snapshots, clones, RWX verified.
IBM Storage FusionIBMFusion HCI appliance or SDS softwareIBM + Red Hat joint pathFusion Data Foundation is Ceph-family (ODF-like). Fusion Access for SAN is the shared-FS path.
Hitachi VSP One SDSHitachi VantaraSoftware-defined blockCertified (SPC)SDS sibling of VSP One Block. Closer to an array SDS than “disks in the hypervisor.”
ODF (purchased)Red HatCeph HCI or external CephFirst-party, designed with VirtualizationNot in the OVE bundle. Use ocs-storagecluster-ceph-rbd with volumeMode: Block, not CephFS.

Portworx on local disks is the default I put on the whiteboard when the requirement is “vSAN, but OpenShift.” The compatibility article lists local disk, FlashArray, and third-party arrays under Portworx Enterprise, with OpenShift Virtualization and VDI. You are not locked into HCI forever.

PowerFlex is the Dell HCI/SDS answer. PowerMax and PowerStore are the Dell array answers. Unity XT is a different conversation: the lab path in Dell Unity over iSCSI can attach block, but Unity is often missing from the OpenShift Virtualization column of Dell’s CSM matrix even when PowerFlex is listed. Do not assume every Dell CSI driver is virt-capable.

LINSTOR is the interesting lightweight option. LINBIT ran Red Hat’s CSI e2e suite and the kubevirt-storage-checkup (live migration, RWX, snapshots, clones, hot-plug, expansion). Support is LINBIT, not Red Hat storage support. That is acceptable for many OVE designs if the account wants DRBD-style local NVMe without a Ceph control plane.

IBM Storage Fusion is the IBM HCI path. Internal disks go through Fusion Data Foundation. Existing IBM SAN can stay on IBM block CSI (FlashSystem, SVC, Storage Virtualize) or move to Fusion Access for SAN. Prefer raw block for VM disks.

simplyblock and Lightbits market NVMe/TCP SDS as an ODF/vSAN alternative and show up in catalog or vendor virt pages. They were not on KCS 7128992 when I last checked. Treat them as evaluation candidates, not the default shortlist, until the vendor shows a current OpenShift Virtualization badge for your OpenShift version.

Certified arrays: keep the SAN, skip the HCI story

If the disks already live in an array, you are replacing a VMFS/NFS datastore, not vSAN. Use the vendor CSI. Confirm RWX (block or NFS), snapshots, and clones.

VendorProductTypical protocolOpenShift Virtualization
Everpure / PortworxFlashArray via Portworx CSI or PX EnterpriseiSCSI, FC, NVMe/TCP, NVMe/RDMAYes, including VDI
DellPowerMax, PowerStore, PowerFlexFC, iSCSI, NVMe/TCP, NFS (varies)Yes via Container Storage Modules
NetAppAFF / FAS via Trident (certified operator)iSCSI, NVMe/TCP, NFS, SMB; FC tech previewYes, including VDI. Use SAN raw block or NAS for RWX live migration.
IBMFlashSystem, SVC, Storage Virtualize, DS8000FC, iSCSIYes via IBM block storage CSI
HPEAlletra / Primera / Nimble; XP8; GreenLake FileFC, iSCSI, NFS, NVMe (XP8)Yes via HPE CSI operators
Hitachi VantaraVSP One Block; VSP One SDSFC, iSCSI, NVMe-oFYes via Hitachi Storage Plug-in for Containers
InfinidatInfiniBoxFC, iSCSI, NFSYes
ArcteraInfoscale for KubernetesFC/SCSI on Hitachi, Pure, or VMware VMDKYes — shared-disk file system model

NetApp Trident’s SAN drivers do RWX in raw block mode. Filesystem mode on those drivers is RWO. Live migration cares about that distinction more than the brand on the array.

If you are migrating from VMware and the disks already sit on a SAN, storage copy offload can matter more than which HCI you pick. See storage copy offload for VMware migrations.

Looks local. Does not replace vSAN.

OptionWhy it is not the analog
LVM Storage (LVMS / TopoLVM)Local RWO only. No cross-node replication. Live migration blocked.
Local Storage Operator / hostPathStatic local PVs. Same node affinity. Fine for a lab, not HA VMs.
StorMagic SvSANTwo-node HCI aimed at vSphere/Hyper-V. CSI docs target Tanzu on VMware, not OVE.
StarWind VSAN, Longhorn, OpenEBSMay replicate local disks. Not on the Red Hat Virtualization compatibility article. You own live-migration proof.
Nutanix AHV as the hypervisorDifferent hypervisor. Nutanix CSI can attach storage to OpenShift in some designs. That is not OVE + Nutanix vSAN.

How I would choose on an OVE cluster

If the requirement is local disks like vSAN, shortlist Portworx on local disks, Dell PowerFlex, LINBIT LINSTOR, or IBM Fusion HCI. Portworx is the most common OpenShift Virtualization HCI path. PowerFlex fits Dell SDS accounts. LINSTOR is the lightest certified replica of local NVMe. Fusion is the IBM appliance/software path.

If a SAN already exists, use the vendor CSI. Do not add ODF “because that is what the slide said.” ODF is still the right buy when you want first-party Ceph, one stack for block/file/object, and Red Hat storage support on the same ticket as the cluster. A PoC ODF install is in OpenShift Data Foundation (OpenShift PoC); array CSI examples start from Storage.

Starting with OpenShift 4.17, CSI certification includes the kubevirt-storage-checkup suite. A driver can pass generic CSI tests and still be a poor VM backend. Ask the vendor for RWX Block, snapshots, clones, live migration, and the catalog badge for your OpenShift version—not just an older release.

Listings in this post are a snapshot, not a support statement. Re-check KCS 7128992 and the Ecosystem Catalog before procurement.

The solutions architect takeaway

  1. Local disks like vSAN — shortlist Portworx, PowerFlex, LINSTOR, or IBM Fusion HCI. Portworx is the usual OpenShift Virtualization HCI path.
  2. A SAN already exists — use the vendor CSI. Do not add ODF because a slide said to.
  3. Ask for the virt badge — RWX Block, snapshots, clones, live migration, and the catalog result for this OpenShift version.

Further reading

Want help mapping vSAN-like storage onto an OVE landing zone? Reach out to your Red Hat account team—or prove RWX Block live migration on a non-prod OVE cluster before you standardize on a StorageClass.

This post is licensed under CC BY 4.0 by the author.