citrix xenserver

Last week we happened to be at VMware’s headquarters when Microsoft launched Hyper-V, Redmond’s much anticipated built-in hypervisor for Windows Server 2008. So we got our camera rolling to capture VMware’s reaction on Microsoft’s free hypervisor offering. Straight after that exclusive interview, we flew from Silicon Valley to New York to collect more video feedback from Parallels. Both vendors calmly welcomed Microsoft to the bare-metal hypervisor market and underlined Hyper-V is only a first version product release from Microsoft, missing critical features, which virtualization spoiled clients can no longer miss in their datacenters.

The video is also up on YouTube, Steamocracy and Blip.tv.

As an introduction to novice readers, we shortly explain the difference between Hyper-V (a bare-metal hypervisor), and the older Virtualization products Microsoft has been marketing, such as Virtual PC and Virtual Server (sometimes confusingly referred to as hosted hypervisors). Hyper-V is a bare-metal hypervisor (commonly referred to as Type 1 or Native Virtualization), which is software that runs directly on the hardware, as an operating system control program. A guest operating system such as Windows, Solaris or Linux thus runs at the second level above the hardware. This means Hyper-V is only a thin abstraction layer which boots on the native hardware and thus provides hardware abstraction services to the operatingsystem environment (performing some of the functions of an OS kernel). This differs from hosted hypervisors (commonly referred to as Type 2 or Host-Based Virtualization), which is software that runs within an operating system environment (Host). A guest operating system (Virtual Machine) thus runs at the third level above the host and the underlying hardware. Bare-metal hypervisors are supposedly faster and more enterprise scalable. The disadvantages are most of these hypervisors are hardware dependent and usually require hardware support to get the most out of the virtualized feature set (i.e. Intel VT or AMD-V processors).

At VMware we got a first reaction on Hyper-V from John Gilmartin, Group Manager, Product Marketing: “Hyper-V is a first generation product. It is a hypervisor that runs virtual machines and that is what Vmware has been doing since back in 2000-2001. What it doesn’t offer is a whole set of virtual infrastructure capabilities, that would run on top of a hypervisor. Things like: Live migration with VMotion or resource scheduling for load balancing Virtual Machines. These are really fundamental capabilities that our customers tell us are required for doing production consolidation or for providing high-availability for virtual machines or for running a disaster recovery solution on top of Virtualization. So from our perspective Hyper-V is a first generation product. Our customers are asking for a whole rich virtualization set of virtual infrastructure software that goes well beyond just a hypervisor.”

Kurt Daniel, Senior Vice President, Marketing and Online at Parallels went on to add “…we actually are a big partner of Microsoft and them of us in the hosting and Software-as-a-Service-markets for Virtualization and Automation. In the general market we see Hyper-V as being late to the market and having a platform deficit… It is also a little bit of ‘now you see it and now you don’t get it’-Virtualization in terms of missing live migration that was initially promised. That is a ticket-to-entry-feature that Parallels offers …Finally we think IT pro’s and developers are not fooled by the low price [free with the Windows Server 2008 OS ]…and we think it does fall short in this early release”

Tony Asaro, Chief Strategy Officer at Virtual Iron summarizes it this way “Even more importantly, Hyper-V doesn’t have the mobility, high availability, recoverability and load balancing capabilities that actually make server virtualization valuable to customers. Yes, it will provide server consolidation, but that is the easier part of server virtualization and for most customers, not where the real value is.”

Sun’s Senior Director of xVM, Vijay Sarathy markets his concerns as follows “We’re glad to see Microsoft finally entering the hypervisor market. Customers are hungry for virtualization solutions that support a wide range of operating systems and virtualization platforms. Simply put, Sun is committed to building a heterogeneous (Windows, Linux and Solaris) and interoperable (ESX and Hyper-V) virtualization platform. To that end, Sun has joined Microsoft’s Server Virtualization Validation Program, supporting Windows as a guest operating system on Sun’s xVM Server hypervisor…With Sun xVM VirtualBox, xVM VDI, xVM Server and xVM Ops Center Sun provides a holistic approach to Windows-focused customers looking for virtualization and management solutions. We’ve already seen great traction with Sun xVM VirtualBox, the industry’s first free and open source hypervisor to offer support for all major operating systems, including Windows, which has already been downloaded more than 5 million times.”

Microsoft’s missing Virtrualization feature list

Reading through the reactions from the competitiors make the missing feature list look something like this:

1. No Live Virtual Machine relocation/migration capabilities: The ability to seamlessly live-move guest virtual machines from one physical server to another is offered by most Virtualization vendors, with products such as VMware VMotion , Parallels Virtuozzo, Citrix XenMotion, … These zero downtime migration capabilities are the most pointed at by the competition, but this cutting-edge feature seems less high on the priority list of SMB virtualization prospects with consolidation on their minds.
2. Platform deficit (limited to Windows and Suse Linux Enterprise). In the glory days of the Bill Gates-era ‘Microsoft Windows’ was almost a synonym for ‘X86 desktop and server operating system’. So supporting a non-windows OS like Suse Linux is a fairly new ball game in Redmond and we are curious how this trend will develop into wider support of guest operating systems and distributions in Linux, BSD and Solaris…
3. No hypervisor virtual machine transformation tools from competitor’s VM-formats into Microsoft’s VHD-format. Those who manage heterogeneous environments are impatiently waiting for the virtualization industry to embrace the DMTF Open Virtual Format (OVF) to ensure portability, integrity and automated installation/configuration of virtual machines. This should allow Microsoft System Center VMM to manage XenServer by using DMTF CIM based interfaces. All this openness with a hypervisor-independent portable virtual machine format promises transformation of a complete application workload with resource requirements, configuration and customization parameters, license and signatures to facilitate appliance integrity and security checking…
4. Unproven and uncertain security levels are an easy and all-time favorite for competitors to throw at Microsoft. However their use of a full version of Microsoft Windows for the parent partition (fully trusted by Hyper-V) seems ‘courageous ’ as it extends the hypervisor attack surface.
5. Limited virtual structure management capabilities. Although this and the next points cannot be expected from a pure hypervisor, many competitors point at an incomplete offering. It should be noted that the Microsoft System Center Virtual Machine Manager 2008 (SCVMM) is currently downloadable in open beta testing and integration can be expected with Operation Manager (SCOM), Configuration Manager (SCCM) and Data Protection Manager (DPM).
6. No resource scheduling for load balancing Virtual Machines (VM)
7. No virtual desktop management

Although Jason Perlow over at ZDnet is quite enthusiastic about Hyper-V, he does point to an additional Hyper-V Manager shortcoming when it comes to the administration and guest installation. “Unfortunately, Hyper-V Manager can only run natively in Windows Server 2008 (32-bit or 64-bit) or on Vista SP1, so you will either need to administrate it from a few token Vista machines using the RSAT tools, via RDP connection, or directly from the Windows Server 2008 server console itself. RDP from a Terminal Server client itself is fine, as screen performance and response time is very good and runs even on Open Source Oses. However, RDP is infuriating to work from while a guest OS is being installed for the first time. For some odd reason, Hyper-V actually prevents you from using a mouse in a guest console window until the Integration Tools are actually installed, so you’ll have to be skilled in using the key when installing a guest from remote if you keep XP or Linux at your desk. Hopefully, your datacenter uses IP KVM infrastructure if you don’t want to stand up a Vista system or another copy of Server 2008 on your desk to administrate your remote boxes for those times you do a guest install from scratch.” Jason goes on to applaud Microsoft for “…releasing the Hypercall Adapter into GPL, so both community and commercial Linux distributions will be able to take advantage of Hyper-V” .

We are confident that Mike Neil and his team at Microsoft are working hard to get those ‘missing’ features in future Virtualization product releases and it is believed Microsoft and Citrix/XenServer are collaborating on merging the code additions from the Hypercall Adapter into the upstream Linux Xen Kernel, so that in the future, a separate Hypercall Adapter will not be necessary for Linux.

Independent analyst and blogger Brian Madden boldly predicts that Citrix XenServer might drop Xen as the underlying virtualization engine and switch to Hyper-V in order to put the ‘relationship’ between Microsoft and Citrix back in balance. He reminds us that the Hyper-V and Xen architecture are much alike. We hesitate if IT-relationships make you lose your ‘soul’ so easily, but will treat Brian to a round of free drinks if his unlikely prediction becomes true in the near future. We do know the Xen-community would be relieved to be able to add the Xen brand name to its products again.

It is interesting to read no competitors are hinting directly at potential stability issues, they do all repeat the CIO-mantra of not adopting a Redmond first version for mission critical systems. Even though Microsoft itself relies on Hyper-V for its own datacenters to handle a part of its live traffic.

There seems no more money to be made in ‘basic’ hypervisors (mobile devices might be the short term exception to this rule). So vendors have to excel in a niche or extend to a complete virtualization portfolio where their product offering supports a large number operating systems, with minimal hypervisor overhead to boost guest performance, open API’s and holistic management tools around the hypervisor to easily manage both the virtual and physical infrastructure components as servers, desktops, network, storage while taking care of securityy, high-availibility and disaster recovery. They might even have to throw in a connection broker (VDI). Those broad virtualization vendors that manage to ‘host’ a profitable third-part eco-system around their own products seem to have the best long term perspective for large market adoption.

Our guess is that Microsoft preferred to release an ‘incomplete’ hypervisor 1.0 ahead of schedule to aim for the SMB-market in the short term and get partners on their train. Microsoft sacrified the announced ‘Live migration’-capabilities from the Hyper-V feature set to shorten the time to market. But in a few quarters we expect Microsoft to approach their corporate clients with a Hyper-V 2.0 release that could put them on par with the competition’s richer feature sets. By that time Microsoft might also be able to boast about its fully integrated offering within their management tool family and a wider support of non-Microsoft operating systems and a list add-on products by external partners.

Time will tell. In the mean time we will continue to cover on the hypervisor battles from the trenches of our beloved Virtualization industry.

Talk back in comments below and let us know what experience Hyper-V gives you or which top 5 industry players you expect to rule in a year and for which niche markets; such as the hypervisor market, the host-based virtualization industry, virtual desktop infrastructure or even for the holistic virtual and physical infrastructure management suites.