Comparing RHEV, vSphere, and Hyper-V – pt 1

Today’s post will be the first in a short series of comparisons between RHEV 3, vSphere 5, and Hyper-V. This first post will cover the cost comparison between the 3. And while most of the time I like to wait until the end to announce the overall results, I think you can figure it out on your own that my own bias is towards KVM or KVM-based virtualization. So, in the spirit of “cutting to the chase”:

RHEV FTW!! Woohoo!! End of article!! (Just kidding about the last part.)

Here are some assumptions and other information. The pricing is based on “list”, so there is no reflection of any discounts that you might be entitled to as a customer.  Additionally, I am aware that Red Hat, Microsoft, and VMware all have different pricing models, so a true “apples-to-apples” comparison is challenge. And if you didn’t know it, they all do that on purpose.

Last, the pricing comparison includes the Management Tools, Support, licensing, Hypervisors, and Operating Systems necessary to virtualize 50 RHEL servers and 50 Windows servers with the following specs:

  • Hypervisor servers each have 2 x 6 core CPU’s (RHEV & vSphere) and 64GB of RAM (Windows Server 2008 Enterprise Hyper-V requires 4 x 6 core CPU’s….)
  • Support is Premium 24×7
  • Live Migration & VM Failover
  • 50 x RHEL 6 guests
  • 50 x Windows Server 2008 Enterprise guests
  • The cost calculator used was built by “Alinean”

So, how about some charts and numbers? This first chart breaks out the different costs associated with the initial investment (1st year) as well as the additional costs over time (3 year TCO).

TCO Chart 1

Now, the more observant reader is going say “Wait a minute, you bumped up the server cost for Hyper-V!!” Yes, yes I did. It was either bump up the number of physical servers or lower the number of virtual servers; Hyper-V doesn’t support the same guest density as RHEV or vSphere. And since I already said we were comparing an equal number of virtual servers, it meant bumping up the physical hardware requirements.

The other visual discrepancy for Hyper-V is the notion that it costs more to run Windows on Windows.. If it costs $24k to run Windows on RHEV or vSphere, shouldn’t it cost $24k to run it on Hyper-V? Not really. You either have to purchase “Enterprise Edition” with a few included Windows guest entitlements or upgrade to “Datacenter Edition” in order to get unlimited Windows guest entitlements. Standard Edition is not really an option as it doesn’t include basic features such as Live Migration of guests.

In other words it’s cheaper to run Windows on RHEL…

As for the VMware pricing, it comes down to this: VMware charges for the licenses and support. Red Hat does not charge a license fee or annual maintenance fee – only the annual support subscription.

So lets take a more visual approach to where the money is going:

So, here is what we can glean from this second chart:

  • Hyper-V requires additional hardware & licensing (SCVM) for the same number of VM’s
  • VMware requires a substantial amount of $$ in licensing in addition to support
  • Red Hat’s lack of license cost and lower hardware requirements are a huge money saver

That’s part 1, pure and simple. Red Hat has a lower initial investment and a lower TCO over 3 years.


13 thoughts on “Comparing RHEV, vSphere, and Hyper-V – pt 1”

  1. I’m still confused about the Windows licensing costs. You’ve stated that you have to buy various editions to get the virtualisation rights (Datacentre etc) but isn’t still that true if you go with Hyper-V or RHEV?

    1. Hi Ed,

      Thanks for taking the time to reply. In both vSphere and Hyper-V, there are multiple levels of product. Each higher level provides more features and functionality than the previous as well as additional cost. For example, vSphere 5 is offered in Standard, Enterprise, and Enterprise Plus (and some others, just trying to keep the example brief). Enterprise has more features and associated cost as compared to Standard. Enterprise Plus, even more so. Microsoft has a similar tier for Hyper-V.

      When you purchase a support subscription to RHEV, you get all of the features. Period. There is no having to purchase a higher level product for additional cost just to get the rest of the features.

      I hope that clarifies things a bit better for you!

      Captain KVM

      1. i know i am late to the aprty here…but this is only true if your guest os is also some linux distro.

        i think the reason why the windows folks are claiming that hyper-V is free…is that even if you have VMware Enterprise plus, with HA and DRS, or RHEL…you STILL need to buy Windows server Datacenter to perform the HA/DRS functions from a windows POV.

        So for most of us who have to run windows servers in at least some parts of our infrastrucutre…we will still have to buy the windows datacenter license, no matter which hypervisor is actually running the show…ergo, in an odd way…making windows hyper-v “free”.

  2. “In other words it’s cheaper to run Windows on RHEL…”

    This is incorrect.
    Hyper-V Server is free. You may still choose to purchase an Enterprise or Datacenter license per host machine, but this is only for guest OS licensing reasons. This licensing model is the same no matter what hypervisor you use.

    1. Hi Joe,

      Thanks for dropping by. Yes, you could say that technically Hyper-V is free. But if you want to do anything useful with it (live migration, HA for VMs, management), the extra features will cost you. That was my point – that RHEV includes everything for the base price. Because of that, simply stating that “Hyper-V is free and “RHEV costs money, therefore Hyper-V is more cost effective” isn’t necessarily an accurate statement.

      One has to weigh cost, performance, features, and business requirements in order to make an educated decision on a virtualization platform. If you’ve found that Hyper-V satisfies your needs and your budget, that’s great. Honest.

      Captain KVM

  3. Thank you for your answer.
    Actually, this is not quite true either. Hyper-V Server, which is free, is a stripped core-version of Windows Server 2008 R2 Enterprise, with only the Hyper-V role enabled. ALL features, such as HA and live migration etc, are included. There is no license you can buy that will enable any extra features.

    What you must pay for is SCVMM, which is for management only. But this is of course optional. So your original statement that “you either have to purchase “Enterprise Edition” with a few included Windows guest entitlements or upgrade to Datacenter Edition…” is still incorrect. You never have to pay for a Windows license for the parent partition (the hypervisor), only for the guest machines.

    1. Hey Joe,

      Clearly I need to re-check my sources. I’ll post any updates directly to the relevant article(s) and provide you credit for showing me the error of my ways. 😉

      Captain KVM

  4. Thanks for the article, but am so confused about the windows licensing thing, so let me add that the Hyper-V server is free but you need to purchase license for windows for each VM you deploy, the windows Datacenter edition gives you unlimited VMs per server (which is 333 VM’s per host) and the Windows Enterprise the license include four virtual machines for free, if you need more than 4 VM’s you pay windows license as you go. i don’t know exactly how this has been calculated, also for 3 years TCO VMWARE can cost 16x Microsoft (there is a study you can find on the internet). i don’t know a lot about the RHEV but does it include management software like VMWare and Microsoft? VMware have vCenter, vOperation Manager ..etc and Microsoft have System Center Suite.

    1. Hi Naser,

      You are correct that the Hyper-V server is free. The costs come in when you add in the management pieces (that are NOT free), and the licensing as you mentioned. You can purchase individual licenses per VM, or purchase Datacenter version, which is not cheap.

      The RHEV management comes with the subscription. And this is actually one of my points – if you purchase the subscription for “RHEV for Servers”, you get everything. There are not additional upgrades or features to purchase. The cost comparison that I referenced is an attempt to compare things as equally as possible.

      I hope this answers your question,

      Captain KVM

      1. Worth noting that RHEV subscription costs are much higher than the relatively low costs of using SCVMM to manage Hyper-V. And you can choose to use other management suites or just Powershell if you desire.

        Things that come included for free with Hyper-V like resilient storage, clustering, and smart management are all expensive add-ons for RHEV.

        Plus of course RHEV tend to have a higher TCO anyway as KVM doesn’t scale as well as Hyper-V 2012, and you have an order of magnitude more security patches to evaluate and test with a Linux based distribution…

        1. Hi,

          First off, thanks for taking the time to post a response. Please note that while I disagree with you, I have zero animosity towards you. Please keep that in mind as you read my response.

          I’d love to see where Hyper-V + SCVMM is cheaper than RHEV. Unless the licensing went down with Hyper-V 2012, the total cost of it is more expensive than VMware. If you choose not to use SCVMM, then the cost goes way down. But I can do the same with Red Hat. I can purchase ‘premium’ support for RHEL 6 and get unlimited VM licenses for it, and use anything I want to manage it.

          As for things like resiliant storage and clustering, I will argue that they are unnecessary to begin with.

          For example, Resilent Storage (GFS2) is a clustered file system and there isn’t a use case for it in the context of RHEV. If you’re using NFS, then you already have the ability to read/write from many clients. If you’re using SAN, then RHEV simply uses clustered LVM under the covers, so again, GFS2 is not needed. If you’re virtualization environment is important enough to warrant resiliency, then you will likely have enterprise storage anyway.

          As for the Clustering Add On (Red Hat Cluster Suite), it’s meant to re-start an application on a failover node should the node it’s running on fails for any reason. RHEV already includes the ability to automatically restart VMs should the hypervisor they’re running on fail. In other words the Clustering Add On is not needed.

          For the TCO, I’d love to see a TCO study that reflects your statement. KVM has traditionally outscaled and outperformed (SPEC_virt, VMware, and VMware can handle more VMs per host than Hyper-V. Hyper-V takes more hypervisors to support the same number of VMs (

          Last, the security patches argument that you present is a common a misleading talking point from Microsoft and VMware. There are no more patches in Linux than there are in Windows or VMware. If your RHEL system is supported and registered, then it is easy to log into RHN (not an extra cost) and view not only what updates are available, but which specific systems are impacted. From there you can apply the same patch to all affected systems at once. I fail to see how this is better/worse than MS or VMware. As for VMware, their dirty little secret is that it’s still RHEL under the covers. The other discrepancy with your patch/update argument is that for your previous points you cited Red Hat specifically, but for the patches you generalized Linux. While there are 4 or 5 primary ways of managing updates in the Linux community, RHEL/RHEV uses a consistent, repeatable, and scalable means of patch management.

          Again, no animosity here, I just disagree with your assertions. By all means, feel free to counter; I like a healthy/respectful debate.

    1. Hi Rich,

      In my opinion, it’s all about pro’s and con’s weighed against business needs. Let’s take this blog as an example – while I’m perfectly capable of maintaining my own servers, operating systems, and blog applications, I don’t want to. I want to focus on writing posts and answering comments. So to balance it out, I pay someone else to host my application. With any virtualization platform, you are maintaining your own servers, operating systems, applications, and development. But, the benefit is that you maintain control of everything – dev cycles, performance, tuning, etc. I have no say in how my service provider does anything behind the scenes – but then again, in this particular case I’m ok with it.

      With something like AWS, you pick your platform and focus on the application and the data. You pay a metered price, and you don’t worry about anything below the application layer (servers, hypervisors, storage, etc.).

      Another way to look at it is the difference between “SaaS”, “Paas”, and “IaaS”:

        SaaS, or Software as a Service is where you can access your data from anywhere that you can get an internet connection. Examples would be Gmail, Yahoo Mail, or this blog. We have no say in the server/storage/application stack.
        PaaS, or Platform as a Service is where developers can write their own code, but the tools are provided. You just add your data. For example, from a dev standpoint, Facebook is a PaaS – they provide the framework and tools, you write your code and they host it. You still have no say in the server/storage/application stack.
        IaaS, or Infrastructure as a Service is where someone provides the hardware stack, but you deploy or choose the operating system, applications, coding, and data. AWS fits in here.

      So where does a virtualization platform fit in? Well, it could be used as the foundation for any of these “as a service” stacks. AWS uses a lot of Linux and Xen, Microsoft uses Hyper-V for Azure, I know of many other service providers that use KVM as an internal cloud (IaaS) platform.

      Hope this helps,

      Captain KVM

Agree? Disagree? Something to add to the conversation?