Reviewing VMware Cloud on Dell EMC
Nathan Biggs (@nathanbiggs), CEO
Today at Dell Technologies World, VMware and Dell EMC announced VMware Cloud on Dell EMC, a fully-managed cloud that is deployed on premises at the customer site. This is an exciting announcement, and one that helps close a gap for customers in developing their cloud strategy.
VMware Cloud on Dell EMC Overview
When considering a cloud strategy, many customers have weighed the trade-off between flexibility and control in several areas. Some of these considerations include the following:
Fixed depreciable assets
Deploy only as needed
|Operations||Multiple control views||Single pane of glass|
Traditionally, the cloud provided flexibility and elasticity, while on-premises infrastructure provided control and mixed-platform options. VMware Cloud on Dell EMC however, helps to provide the best of both scenarios. It allows for on-premises control, while also providing a fully-managed cloud experience.
Questions for Running Enterprise Applications
As is our practice at House of Brick, we evaluate all on-premises and cloud deployment options based on the impact on the enterprise applications that will run there. Here are some of my questions going into the review of VMware Cloud on Dell EMC:
- What hardware configurations are available?
- Can we disable processor cores to limit application vendor licensing impacts?
- Will the compute functions and storage control be combined on the same compute nodes?
- What happens to the VMs when maintenance needs to be performed on the compute nodes?
- What options are available for limiting application workloads to a subset of a Software Defined Data Center (SDDC) rack?
The answer to each of these questions has a considerable impact on vendor licensing, for example business-critical systems like SQL Server, and Oracle databases. Using Oracle as an example, the customer must license every processor core where the Oracle software is “installed and/or running.”
Exploring the Answers
VMware Cloud on Dell EMC is based on VxRail nodes with either one-socket (Host type G1) or two-socket (Host type G2) configurations. The G1 option will have 20 cores per host, and G2 will have 36 cores per host (Question 1).
This is a very high core-count for processor-based licensing (like Oracle Database). I assume that VMware Cloud on Dell EMC SDDC deployments will have the same option for core-disablement at order time that VMware provides for the VMware Cloud on AWS. I did not see that option on the sample order screens shown in the VMware presentation however, so this is an outstanding question for us (Question 2).
VxRail deployments typically (but not always) combine the storage control for vSAN on the same nodes where the applications will be running. For vendor software like Oracle, this combination dilutes the very costly investment in processor metric licenses. The VMware Cloud on Dell EMC presentation made a very important announcement regarding storage. The customer will be able to mount existing non-VxRail storage to the rack through vCenter. This will be vital for our clients who have existing high-performance storage for their enterprise applications, with separate non-licensed storage control CPUs from the application compute processors (Question 3).
With the VMware Cloud on AWS, VMware will periodically add a +1 node to the cluster and use it to migrate virtual machines during host maintenance. Based on the slide in the presentation entitled “Lifecycle and Availability Managed by VMware” I assume that this is the process that will also be followed for VMware Cloud on Dell EMC. This is a very effective mechanism for node maintenance, but it has a potentially costly licensing impact for workloads like Oracle Database. If a customer has four nodes in their VMware Cloud on Dell EMC SDDC, and has licensed those four nodes for Oracle, then adding a fifth node with virtual machines with Oracle running on all five (even if for a short period of time) would potentially put the customer out of license compliance. Sufficient licenses need to be allocated to cover the +1 node scenario (Question 4).
The presentation did not cover host affinity rules, which could be used to limit the nodes in a VMware Cloud on Dell EMC SDDC rack on which certain virtual machines could run. In describing DRS rules for the VMware Cloud on AWS, VMware stated:
“Affinity policies in VMware Cloud on AWS SDDC are not the same as vSphere DRS affinity rules created on-premises. These can be used in many of the same ways but have significant operational differences. A compute policy applies to all hosts in an SDDC and cannot typically be enforced in the same way that a DRS must policy is enforced.”
The “must” policy that is mentioned in this description is an important capability to ensure that virtual machines always stay on licensed hosts for those applications that are licensed by the underlying hardware. It will be an important question to answer as to whether the VMware Cloud on Dell EMC behaves the same way as its VMware Cloud on AWS counterpart, or whether it may have some of the flexibility of on-premises vSphere deployments (Question 5).
While there are questions that still need to be answered, the announcement of the VMware Cloud on Dell EMC is a fantastic option for House of Brick clients looking to develop their cloud strategies. It brings the best of cloud flexibility to the control and physical security of the on-premises environment. The potential impacts on vendor licensing can be addressed through the smart design and deployment of these solutions, while strictly adhering to an application’s licensing terms and conditions. We are thrilled with this announcement, and look forward to working with our clients on adding the VMware Cloud on Dell EMC to their cloud strategy.