The latest version of Citrix Systems' server virtualization platform now supports more powerful hosts, and some editions have new features, including live memory snapshots. Another new feature, dynamic memory, will help Citrix XenServer 5.6 fit into your customers' cloud environments because of its ability to distribute resources. The question is, will these capabilities help increase user adoption?
Expert Sander van Vugt talks to Colin Steele, our site editor, in this Q&A about what's new in Citrix XenServer 5.6.
SearchSystemsChannel.com: One of the new features in XenServer 5.6 is that it can now support up to 256 gigs of RAM per host and up to 64 logical processors. How much will these, and some of the other new capabilities, help solutions providers attract new customers?
Sander van Vugt: Well, to be honest, I think this is just a cosmetic change, because who wants to run machines that use that much memory and logical processors on one VM host? Typically what I see from different customers is that people tend to run the larger and heavier machines still directly on the iron and not in a virtualized environment.
So it looks good, and it certainly makes sure that XenServer compares better with other virtualization solutions, such as VMware or the Microsoft solution, but to be honest, I haven't seen one single customer that runs virtual machines that go beyond, like, 16 gigabytes of RAM. So will this help attract more customers? I'm not sure. I don't think so.
SSC: Are there any new management tools in XenServer 5.6, and how much of an improvement are they?
Van Vugt: Well, to be honest, I haven't found any new management tools, just XenCenter as it was before.
SSC: Is the new version of XenServer available for free? And what are some of the major differences in editions?
Van Vugt: There are four different versions of XenServer. There is XenServer Free, which is named Free because, well, it's free. And then there is Advanced, Enterprise and Platinum. Advanced (has) high availability and dynamic memory, which means that virtual machines can adjust their memory assignments dynamically.
If people need more than just these features, the Enterprise version is the next step. Two important items that you'll find in there are live memory snapshots, which make it a lot easier to manage virtual machines in a large environment, (and automated workload balancing). Live memory snapshots, in my opinion, is the most important new item in XenServer 5.6. The idea with live memory snapshots is that you can just pick any state of a virtual machine and make a snapshot of that and then revert to the previous state if you run into trouble. Automated workload balancing … means that virtual machines are moved from the host computer if the host computer gets overloaded.
And then there's the Platinum version. The Platinum version is for large sites only. What makes it different is that it includes site recovery features.
SSC: How does this new version of XenServer fit into the cloud computing plans that a lot of resellers and their customers have?
Van Vugt: Well, I think that the cloud computing solution that Citrix is offering can benefit pretty well from the new XenServer. … Especially interesting for cloud environments is the (ability) to do automatic workload balancing (and) the new dynamic memory management feature.
I think these items are important to support a cloud environment. … They fit into a global strategy of cloud computing, but they don't make a cloud solution by themselves.
SSC: And finally, will the new features and capabilities in 5.6 stand up when compared to Hyper-V R2 and vSphere?
Van Vugt: Hyper-V, I don't know that well enough, but as compared to vSphere, which is the most important player on the market -- well, at least in my part of the planet -- XenServer really lacked overcommiting memory. This feature allows multiple machines to have more memory assigned than is physically present in the host computer. Now XenServer 5.6 has that implemented as dynamic memory control, and that makes sure than at least XenServer 5.6 is comparable to the VMware offering.
So does it make XenServer better than VMware? I'm not sure about it, but it at least makes sure that XenServer can compete at more or less the same level as VMware. But of course there are always small features that are missing from one or the other solution, which in particular environments may be pretty important.
About the expert
Sander van Vugt is an independent trainer and consultant living in the Netherlands. Van Vugt is an expert in Linux high availability, virtualization and performance and has completed several projects that implement all three. He is also the writer of various Linux-related books, such as Beginning the Linux Command Line, Beginning Ubuntu Server Administration and Pro Ubuntu Server Administration.
This was first published in August 2010