Hyper-V vs. ESXi in the Small Business space
Disclaimer: I work for a Microsoft Partner. So i’m probably biased.
Virtualization has always been a topic with a lot of hype, but as of today we have a single customer that is using it (out of 150).
Why? Because virtualization is still expensive. For larger companies, it was possible to save money by using virtualization, for smaller companies that wasn’t really the case. You’ll still need to license the guest OS. You’ll still need to maintain it.
Most customers decided to just buy a Windows Small Business Server, and run all apps from that machine. Though that usually required a technician that knew what he was doing to get all the apps running together on a single machine, it saved money in licensing cost and hardware - and the most important application ran on a separate machine anyway (our ERP software on the IBM i).
With the release of Hyper-V and it’s inclusion in SBS 2008 Premium (on the second machine), Virtualization will probably get picked up even in small businesses. But is it the right way?
I’ve started gearing up my knowledge on virtualization as it will become a topic for our customers. For that, the most important other factor is VMware. VMware offers virtualization products for longer than Microsoft, and i’ve been using their Workstation product for a long time.
Microsofts Desktop product Virtual PC is lackluster at best. The performance is awful and it doesn’t offer many features. There was also Virtual Server 2005, which we’ve used internally since mid-2005 (when you still had to purchase GSX Server and we got VS2005 through the MSPP for free).
Now VMware has an offering that is free, Microsoft has an offering that is included into most Windows Server licenses and Citrix offers a very limited edition of their product for free (Max 4GB RAM, Max 4 VM).
And the big question would be - what product should a small business use today, and why?
I’ve found a few good blog posts on ESXi:
What’s the difference between free ESXi and licensed ESXi?
And on Xen:
Citrix XenServer for the ESX Engineer
And on Hyper-V:
Hyper-V for the ESX Engineer
More on Hyper-V for the ESX Engineer
On ESXi
ESXi Installable Edition Free (short: ESXi) only runs on certain certified systems. Of course you can still build a whitebox machine that runs ESXi, but that would be a rather stupid decision. Running supported hardware is important even in a small business.
ESXi doesn’t support many systems, especially our bestseller system, the IBM x3650 is not supported with ESXi installable edition. I expect the list of machines supported by ESXi to grow steadily, though.
On the other hand, ESXi supports a wide variety of guest operating systems that are supported by VMware. This is one of the main advantages VMware has over Hyper-V. However, most Small Businesses struggle with the complexity of using one operating system. They are unlikely to use multiple ones. On the other hand, VMware offers preconfigured appliances, which sounds like a good use. Important to know: Microsoft does not directly support running Windows on VMware unless you pay big for a Premium support contract.
ESXi can be managed by the VMware “VI Client”. This allows you to do all the everyday tasks of configuring and setting up virtual machines.
ESXi doesn’t have any restrictions that would prohibit production usage, but the management features are a bit limited - you can’t monitor it using SNMP, you can’t script it using the RCLI. If you want those features, you’ll have to pay.
VirtualCenter, which is VMware’s variant of System Center Virtual Machine Manager, is quite expensive. Of course, SCVMM is also quite expensive. So i doubt that either will be used in a Small Business. The disadvantage i see here over Hyper-V is the fact that it can’t be scripted or automated. While not a showstopper, it’s important to consider this.
On XEN
The free XEN version supports a maximum of 4 VMs and 4GB of RAM. With that, i think everything is said and done. These restrictions do not allow production usage. It’s more like a demo version for the full products.
On Hyper-V
Hyper-V only works on 64bit installations of Windows Server 2008 Standard, Enterprise or Datacenter. In SBS 2008 Premium, one license for Windows Server 2008 Standard is included. This allows small businesses to get started with Hyper-V. WS2008 Standard x64 supports up to 32GB RAM. If you use “just” Hyper-V on a WS2008 Standard installation, you can also install a single guest VM with WS2008 Standard without having to purchase an additional license. Be aware that it does not work this way if you run any other software like SQL Server on the Hyper-V host.
Hyper-V can run on a lot of hardware, as described in the Windows Server Catalog. It is also a lot more flexible when it comes to storage configurations, as Windows supports more disk controllers than ESXi.
Hyper-V can be automated using WMI, there is no direct PowerShell support (though you can use PowerShells WMI support).
You can deploy Hyper-V on Windows Server Core, as a dedicated VM host. Managing Hyper-V in this scenario requires a machine running Windows Server 2008 or Windows Vista with the Hyper-V management tools installed. This is the recommended deployment mode.
You can also install Hyper-V on a full Windows installation. Though not recommended, this allows you to logon to the machine using RDP and manage the VMs directly on the server using the same Hyper-V management tools.
Here is one of the biggest advantages Hyper-V has over ESXi. For example, if you setup the WS2008 Standard Server as a SQL Server, you can install Hyper-V after the fact with a simple reboot. Though this is not what Microsoft recommends, the reality is that most Small Businesses have to achieve a lot with less equipment. Running such a configuration can help fix business problems without having to reinstall a machine.
System Center Virtual Machine Manager allows you to manage Hyper-V centrally. It’s quite expensive, so i doubt many small businesses will start using it. Maybe the next version of System Center Essentials will include a subset of SCVMM functionality.
Conclusion
Hyper-V supports more hardware, and is more flexible when it comes to it’s deployment. For me, this makes Hyper-V the better choice for a Small Business than ESXi. XEN Express is absolutely unusuable in a production deployment.
Now, Enterprise admins will probably slap me for the “flexible” deployment of Hyper-V, and they are right. But for most small businesses, being able to cut corners in IT is more important than running “recommended” configurations.
I’m using Hyper-V standalone on a machine in a hosting center to run my private infrastructure (where i plan on moving this blog to), and it’s also a full Windows installation. Hyper-V runs flawlessly in such a scenario.
I also didn’t talk about Vmotion, HA, DRS and all the other fancy features that VMware has and Hyper-V doesn’t have yet - simply because they do not matter to a small business.

Aaron Delp:
Thank you for the links! Very good post!
-Aaron
11. August, 2008, 17:20ESXi - A perspective from the Microsoft World » Lukas Beeler’s IT Blog » Blog Archive:
[...] Links « Hyper-V vs. ESXi in the Small Business space [...]
14. August, 2008, 15:30Oczkov:
Some important updates to this blog article:
1.) with ESXi 3.5 Update 2 IBM x3650 is supported for sure :) The list of supported servers is growing as expected by the author of this blog
2.) Microsoft does support Windows and other server products on VMware ESX Server 3.5 U2 since VMware joined the Microsoft Server Virtualization Validation Program (SVVP) program and as the first vendor on the market finished the validation with success:
http://vmware.com/company/news/releases/svvp.html ESXi 3.5 is not mentioned, however. I assume this is only a matter of time since ESXi technology will be the mainstream in VI4 (next generation of VI).
3. I am sure you can use a limited SNMP functions of ESXi, as per documentation: ESX Server 3i ships with an SNMP management agent different from the agent that runs in the ESX Server 3 service console. Currently, the ESX Server 3i SNMP agent supports only SNMP traps, not GETS and is off by default.
4. You can script ESXi using RCLI (both on Windows, Linux and on RCLI standalone appliance, which is based on stripped-down Debian clone (why Debian??!)) More, ESXi can be scripted with PowerShell (VMware publishes the VMware Infrastructure Toolkit for Windows) http://www.vmware.com/download/vi/drivers_tools.html).
5. As System Center Virtual Machine Manager tries to offer what VirtualCenter does, the VirtualCenter can be purchased as VC Foundation Edition, which is about 30% of the price (1495 USD list price + support) and offers FULL functionality, but is limited to manage up to 3 physical ESX hosts (no matter how big they are!). This seems like a more than an alternative to SMB shops and System Center VMM or Esentials from Microsoft.
Anyway - great blog! Thanks.
Cheers,
17. September, 2008, 16:25Oczkov
Lukas Beeler:
Hi,
1.) It’s not on the list as of yet.
2.) Yep, that changed recently. This is a very good change, because it levels the playing field for competitors.
3.) These limitations are for the free ESXi, not for the for-paid ESXi. The free ESXi does not support SNMP.
4.) Again, not the free ESXi. There is a minor feature difference between the payESXi and freeESXi.
5.) SC Essentials does a lot more than VMwares offering, which are limited to VM management. But this appears to be changing…
17. September, 2008, 16:45Oczkov:
1. Correct, the x3350 is supported, x3650 not yet, thought it was x36xx.
22. September, 2008, 16:583. Correct.
4. Correct.
5. Right, but we talk about virtualization and should rather compare SCVMM with VC. System Center Essentials lookes like a crossing of the two well-known MS products: MOM + SCCM (SMS) - with some of the features stripped down. Seems like VMware is not really compeeting on this field. MOM and SSCM is something you would need regardless of the virtualization infrastructure you employ. SCCM has its good but pricy alternative - Altiris.
Madan:
One important comparison between ESXi and HyperV is the footprint. ESXi is about 32MB in size whereas HyperV is around 100MB in size.Ofcourse the Hypervisor in HyperV is only 100kb in size, but the total HyperV install takes about 100MB.
23. October, 2008, 16:23Lukas Beeler:
Madan,
I don’t think this has any impact on running production workloads. Hyper-V server needs more than 100GB, and so does the installable ESXi.
I don’t really care which product is smaller, leaner, etc. but i care about why products helps my customers businesses better. The virtualization market space has changed since i wrote this blog post - Hyper-V Server is out now.
23. October, 2008, 18:30Hyper-V vs. ESXi management » Lukas Beeler’s IT Blog » Blog Archive:
[...] compared Hyper-V and ESXi in the past. Since then, the virtualization market has changed. I was also able to get more [...]
23. October, 2008, 18:47