Hyper-V vs. ESXi vs. XenServer

Solution 1:

I recently took all three for a spin to run my home network, and the short answer is that it depends on your particular needs. Unless your needs are very specialized (database/Exchange/etc), modern hardware with virtualization support you will run the guests with negligible performance differences. Given that I'd suggest looking at features & price.

VMware: As you're probably aware VMware is the long-standing king of virtualization. It has the biggest list of compatible guest OSs, and has one significant unique feature - memory overcommit (you can allocate more virtual memory than there is physical memory). If your goal is to consolidate a bunch of small, underutilized servers VMware will likely give you more VMs/host than anything else. The caveat is that if you overcommit and the VMs need more resources performance tanks. ESX/ESXi also has the smallest list of compatible hardware. If you are looking at a white-box system, check here first. If you have compatible hardware it's fairly easy to install and use. The free version (ESXi) comes with hardly any features, which is fine if you're looking for a few standalone hosts, and the non-free versions are priced out of this world. On a personal note, I VMware leaves a nasty taste in my mouth - in my mind they are one of the many companies resist change & innovation when the very foundation of their business is challenged by the competition. Recently they asked a partner company to remove their product's support for the free version.

Microsoft: Hyper-V is a very intriguing option, even more with the R2 version. I tested Hyper-V Server, which is the free standalone product. I'm a Microsoft fan, and I really wanted to like Hyper-V, primarily because it can run on practically any hardware that has Windows drivers. If you are running in a domain environment and primarily use Windows, Hyper-V should be at the top of your list. When you have the option to buy/use SCVMM it appears to be an even better value. Unlike VMware, the free version comes with a good feature set and is even better in R2, where clustering & live migration are available! Hyper-V runs Windows guests very well, has a small, but growing, list of supported Linux guests, and even unenlightened Linux guests seem to run reasonably well. The story is different if you aren't in a domain environment as managing the standalone Hyper-V Server is a major pain. Despite all of the goods Microsoft delivered in a v1 product, the management was driving me crazy.

Citrix: The end result of my testing was to go with XenServer 5.5. It has IMHO the best set of features and capabilities of the three free offerings. Like VMware it is installed and managed like an appliance rather than an operating system (like Hyper-V). It also has a much larger list of compatible hardware (and I suspect the ability to add drivers if needed). It offers way more features than VMware's free offering, and if you were to upgrade the free version to the paid version would cost much, much less. Windows guests are well supported, but Linux guests are, well, not what you'd expect from a Linux-based virtualization platform. Its list of supported Linux guests is quite small compared to VMware and non-supported Linux guests don't seem to run well at all. Ubuntu is noticeably lacking from the list. Overall for home use I felt that it had the best bang for the buck.

Solution 2:

I thought Xen was a free virtualization platform for Linux...is there a Xen and a separate XenServer platform?

Yes and confusion is common.

• Xen - The HyperVisor that sits behind the scenes.
• XenSource - The open source virtualisation project/solution now owned by Citrix.
• XenServer - The closed source virtualisation product produced by Citrix.

Solution 3:

Quite general what your asking however these are three very big products in the virtualization world, and all offer trail periods i'd advise on taking out testing them on some spare hardware. I can give you my experiences of what I know in the three but would be nice to hear from others too

VMware vSphere 4 First off it's the market leader, and has great dominence over the lot. I costs more but depends what your looking for. ESX (ESXi or ESX HD install) as a single managed host is free. You pay for clustering and management features, HA, DRS+DPM, FT This gives a good comparison vSphere Compare

Other advantages i've found is the CLI and API options. it's endless the amount of automation and support for a large user community. Lots of plug-in's to chose from too.

Citrix XenServer This I'd second as Citrix are great for desktop delivery, and I guess XenServer will be a power product for there suite of stuff. yet to test it. just need to find time but so far it looks neat. It's based on the free Xen.org so it will have a growing user community behind it. This is also on my evaluation list, however ours own IT use it for production VM's, will have to get there views.

MS Hyper-V As MS know they have to enter this industry it eventually mature and match the feature of it's competitors. I'\ve yet to test this hypervizor out.

As regards testing. Make sure you have large servers, 2xQuad CPU's 8GB+ RAM, iSCSI or FC SAN makes a huge difference to test on decent hardware.

Hope that helps ;)

Solution 4:

Cost: XEN and Hyper-V are likely going to be cheaper products in the short run.

Storage compatibility: You really want a decent SAN to drive your storage.

Tools: VMware is king here. VirtualCenter, Lab Manager, LifeCycle Manager, Backup Assistants. Citrix/Xen is only just starting to build tools of this functionality (although the VMware tools CAN be horribly buggy at times).

Solution 5:

Everyone's comments so far are on par with my own experiences. ESXi is a great (free) intro into the VMWare platform. I'd also recommend XenServer 5.5 and XenCenter, both free from Citrix. I currently use Citrix XenServer 5.5 at home and it runs extremely well and XenCenter makes administration so easy. I've been very impressed with the product as a direct competitor to VMWare's product line.

In terms of cost, VMWare is the most expensive but the most mature and stable platform. I'd say Citrix is next in pricing, and MS last as they're practically giving away (~$30?) Hyper-V.

And as usual features come with a price tag. More $$$, more features so I'd say for you maybe the better tactic is to investigate what you think you need first. Then list out features you want. Then work from there, and investigate solutions. Anything extra should be noted.

Opinions and observations would be appreciated for a test rollout for our organization.

So it sounds like your organization is trying to test out the waters. If testing the waters is all you can do, start with price. ESXi 4.0 and/or Citrix XenServer 5.5. If you're strictly running a Microsoft platform, I would recommend Hyper-V as an alternative.