The Delphix Engine is resource intensive from a compute, network, and storage perspective. If the Delphix Engine competes with other virtual machines on the same host for resources, latency increases for all operations. Ensure your KVM host is not over-subscribed to guarantee dedicated resources for the Delphix Engine. Include CPU headroom for the hypervisor itself, which can de-schedule a VM when managing I/O or compute resources.

The KVM ecosystem includes many versions and variations. Delphix generally supports running on KVM, but does not explicitly qualify each vendor's KVM hypervisor solution. Rather, as Delphix is based on Ubuntu 24.04, Delphix supports running on any KVM hypervisor whose vendor supports the Ubuntu 24.04 guest operating system. For example, Delphix is supported on Nutanix AHV and Red Hat OpenShift Virtualization because these are KVM-based platforms whose vendors support the Ubuntu 24.04 guest operating system.

Delphix does not support migrating, copying, or converting Delphix virtual machine images between different virtualization platforms or cloud environments (for example, VMware to Hyper‑V, VMware to KVM, or on‑premises hypervisors to public cloud platforms).

Deployments must use the Delphix image and deployment method provided for the target platform.

Prerequisites

The KVM provider must explicitly state that Ubuntu 24.04 is supported by their variation of KVM.

Most, if not all, KVM hypervisor providers should have public-facing documentation that includes support matrices for guest OS compatibility. If the KVM hypervisor provider does not state support for the Ubuntu version on which Delphix is based (currently 24.04), then Delphix cannot support the KVM provider.

As an example, Nutanix provides a publicly accessible guest OS compatibility matrix for AHV. This matrix includes support for Ubuntu 24.04, and therefore Delphix supports deployment on Nutanix AHV. Oracle Linux also provides a publicly accessible guest operating system support matrix, which also declares support for Ubuntu 24.04. Because of that, Delphix supports deployment on Oracle Linux KVM. Another example is Red Hat, which provides KVM virtualization support in a number of different contexts. While Red Hat does not explicitly list Ubuntu in its certified guest OS support matrix, Ubuntu implicitly falls under Red Hat’s third party support software policy, and Delphix will support deployments in that environment.

Starting with release 2025.5.0.0, newly installed Delphix engines support UEFI boot with secure boot disabled. When you configure an engine via CLI or XML file, include the following parameters:
--boot loader=/usr/share/OVMF/OVMF_CODE.fd, loader.readonly=yes, loader.type=pflash, loader.secure=no

Virtual CPUs

Requirements

Notes

8 vCPUs

  • CPU resource shortfalls can occur on an over-committed host as well as competition for host resources during high IO utilization.

  • CPU reservations are strongly recommended for the Delphix VM so that Delphix is guaranteed the full complement of CPUs even when resources are overcommitted.

  • Use a single core per socket unless there are specific requirements for other VMs on the same KVM host.

Never allocate all available physical CPUs to virtual machines.

  • Reserve a CPU for KVM Server hypervisor activities before assigning vCPUs to Delphix and other VMs.

  • Reserve a minimum of 8-10% of physical CPUs for hypervisor operation (for example, 12 vCPUs on a 128 vCore system).

Memory

Requirements

Notes

128 GB vRAM (recommended)
64GB vRAM (minimum)

  • The Delphix Engine uses its memory to cache database blocks. More memory provides better read performance.

  • Memory reservations are recommended for the Delphix VM. Over-committing memory resources on the KVM Server significantly impacts Delphix Engine performance.

  • Reservations prevent the Delphix Engine from swapping pages under memory pressure on the host. A swapped page can take orders of magnitude longer to restore from the KVM host swap device, severely impacting I/O performance.

Reserve memory for KVM Server hypervisor activities before assigning memory to Delphix and other VMs.

  • Failure to ensure sufficient memory for the host can result in memory exhaustion that blocks allocations for all VMs on the host.

Network

Requirements

Notes

Use a virtual ethernet adapter for network connectivity.

  • Jumbo frames are highly recommended to reduce CPU utilization, decrease latency, and increase network throughput (typically 10-20% throughput improvement).

  • A 10GbE NIC/network is recommended for performance dSource and VDB operations.

Dedicate one or more physical NICs to the Delphix Engine if the network load on the KVM Server is high.

Disk controllers

Both virtio-blk and virtio-scsi controllers are supported for attaching disks to the Delphix Engine on KVM. However, virtio-scsi is the recommended controller: it scales to a larger number of disks per controller, provides more robust hot-plug support for adding and removing disks, and offers broader support of SCSI commands compared to virtio-blk. IDE and SATA controllers are not supported on KVM platforms.

General storage

Delphix disk storage capabilities are based on the backend storage provided. Performance, redundancy, and stability characteristics are determined by the hypervisor or cloud-provisioned storage.

Option 1: Block Storage

Delphix recommends using a minimum of four disks to run your Delphix Engine. One disk is used for the Delphix File System (DxFS) to ensure that its file systems are always consistent on disk without additional serialization. The other three or more equally sized disks will be used for data storage. This also enables the Delphix Engine to achieve higher I/O rates by queueing more I/O operations to its storage.

Requirements

Notes

Provision Delphix storage from a storage solution that provides data protection.

For example, using RAID levels with data protection features, or equivalent technology.

The Delphix Engine does not protect against data loss originating at the hypervisor or SAN layers.

Adding disks to the block storage pool does not require storage device initialization on this hypervisor.

For more information, refer to Optimal storage configuration parameters for the Delphix engine.

Hardware pass-through (direct-attached) disks are not supported.

This includes HBA pass-through (for example, FC/iSCSI HBA passed directly into the guest via PCI/SR-IOV passthrough) or disks exposed directly from a bare-metal server to the VM. Supported configurations require the hypervisor host to mediate storage access and present disks to the guest as virtual block devices (for example, via virtio-scsi or virtio-blk), rather than passing the physical storage adapter or underlying protocol directly into the VM.

Option 2: Elastic Data

One disk is dedicated to the Delphix File System (DxFS), which guarantees on-disk consistency without requiring additional serialization. Additional block storage devices serve as cache, reducing latency for frequently read data and providing temporary storage for synchronous writes before they are flushed to object storage. These block cache devices are set up using the same method as Option 1: Block Storage. This architecture allows Elastic Data with on-prem object storage to be used for database storage.

  • For on-prem object storage, we currently support storage vendors that conform to the following:

    • S3 REST API compatibility

    • Strong read-after-write consistency

    • S3 key ID and secret access key authentication support

    • Perpetual key support

  • On-prem object storage may require a security certificate to create secure connections between the Delphix Engine and object storage. If a certificate is required, install it on the Delphix Engine before configuring storage. Refer to Certificate management for more information.

  • See Initial setup for Elastic Data Engine setup details.

Deploy Delphix qcow2 on KVM

Most KVM users should deploy the qcow2 image that Delphix publishes directly on the Delphix download site (credentials required). This is the supported and recommended format for KVM environments.

Prerequisites

  • KVM host with virtualization enabled

  • Minimum resources (see requirements above):

    • 8 vCPU

    • 128 GB RAM (recommended), 64 GB RAM (minimum)

    • System + data disks as described in the KVM deployment guide

  • Network access per customer environment

Procedure using qcow2

  1. Download the qcow2 image from the Delphix Download Site.

  2. Create a new VM in your KVM environment (for example, virt-manager or virsh).

    1. Assign 8 vCPUs and 128 GB RAM (recommended), 64 GB RAM (minimum).

    2. Attach the qcow2 image as the boot/system disk.

    3. Add additional virtual disks for Delphix data storage.

    4. Thick-provision the data disks to ensure predictable I/O performance. Underlying physical LUNs may still be thin provisioned depending on backend storage capabilities.

  3. Configure networking according to your environment. See General Network and Connectivity Requirements for port and interface requirements.

  4. Boot the VM and continue with your Initial system configuration.

Last updated
Oct 9, 2026