virtualization.info

At the end of August, Citrix announced a new major effort around Xen and cloud computing to counter the release of VMware vCloud Express.

The details of this project were scarce at that time and beyond the name, Xen Cloud Platform (XCP), and the intent to integrate new and existing technologies, Citrix didn’t disclose much more.

Now the things are getting cleaver, with the Xen.org entity detailing the list of proposed components for XCP 1.0 and makes available the platform for download:

• Latest Xen 3.4.1
• Linux 2.6.27 Kernel
• Windows PV Drivers, Microsoft Certified (Binary Only)
• XAPI Enterprise-class Management Tool Stack (web based management interface)
• VM Lifecycle: Live snapshots, checkpoint, migration
• Resource Pools: Safe live relocation, auto configuration, DR
• Host Configuration: Flexible storage management, networking, power management
• Event Tracking: Progress, notification
• Secure Communication using SSL
• Upgrade and Patching Capabilities
• Real-time Performance Monitoring and Alerting
• Basic SR-IOV Support
• CDROM and Network Host Installer
• Full Featured “xe” CLI and web services API

Xen.org also published a tentative roadmap for version 1.0:

• vSwitch Integration - first step to enabling multi-tenant network infrastructure, to enable firewall and routing rules to follow VMs as they migrate, and to enable flexible traffic monitoring of virtual ports
• Netchannel 2 Integration - improve scalability of xen networking on larger systems and to accelerate inter-VM traffic
• SR-IOV Networking - Although Xen support SR-IVO NICs today, configuration requires manual steps. By extending the control strack we can make SR-IOV simply a transparent optimization that is enabled automatically where possible
• Booting guests from SR-IOV HBAs
• Libvirt bindings
• Native support for OVF in the tool stack
• Drive DMTF standards for virtualization and cloud
• Smart error recovery to minimize impact of hardware errors
• Work closely with other projects and vendors to enable web-based mutli-tenant mgmt and provisioning; e.g. Eucalyptus, Enomaly, OpenNebula, etc.
• Increased management scalability for dealing with 1,000s of Xen hosts - federation of resource pools
• Aggregation of cheap local storage - integrated drdb/parallax
• OCFS2 integration

Labels: Citrix, Xen

The article virtualization.info published just last week about Citrix joining the The Linux Foundation generated a lot of interest and comments.
Simon Crosby, CTO of Virtualization and Management division at Citrix, personally answered a few readers about the reasons behind the value of a free XenServer and the strategy behind it.

In doing so Crosby disclosed very interesting information. First he claimed that XenServer costs to VMware $300MM per year in lost revenue, probably a Citrix internal projection considering its current market share.

Much more important than that, today Crosby candidly unveiled that Citrix is about to fully open source XenServer.
You read right: the company CTO is not talking about Xen, which is already developed and maintained by the open source community. He’s talking about its commercial implementation, XenServer, where Citrix invested so far, that is offered as a free product since February and that the Burton Group considered as enterprise-ready as VMware ESX.

Here’s his full answer that contains the breaking news:

XenServer is 100% free, and also shortly fully open sourced. There is no revenue from it at all. That is strategically aligned with our goal to increase market share, get directly to customers and also provide Citrix customers with virtualization built into our core products as a core capabiliy, so every XenApp customer has free support for XS built into their XenApp entitlement, ditto for XenDesktop. Our positive revenue comes form Essentials for XenServer and Hyper-V, which adds all of the automation functions for management of virtualized environments and self-service virtual lab and stage management. This is a substantial business, growing rapidly, but also offers customers value through inclusion in the value-added stacks (Enterprise/Platinum editions) of XenDesktop and XenApp. It is therefore not possible to make a direct head to head comparison with VMware, which doesn't have a competitor to XenApp, and whose competitor to XenDesktop doesn't scale at present.

Crosby further confirmed his words after the comment above.

This move may or may not increase the Citrix market share, and may or may not oblige VMware to drop the price of ESX earlier than expected.
virtualization.info will publish additional details as soon as they are available.

Meanwhile it’s worth considering what Oracle and Novell will do after this will be formalized.
Both companies have their own implementations of Xen, and both are working to release more sophisticated platforms that offer the same features that XenServer offer today.
If Citrix gives away the code, does it make any sense for Oracle and Novell to continue their own development of the hypervisor?

It will also be interesting to see if this move will generate more virtualization players, as it makes so much cheaper and easier to enter the virtualization market by focusing just on the management layer.

Update: Citrix reached out virtualization.info to add an official statement to this move:

XenServer is offered to the community as the basis for the Xen Cloud Platform (XCP).  There will be substantial additional contributions coming from other community partners, but we aim to make all of our technology in XenServer (other than XenCenter, which is a stateless Microsoft .NET client GUI and therefore not appropriate for the XCP community and its intention to make a great cloud platform for large scale clouds to consume and automate using their automation and management systems) available to the community in OSS. 

Other features will come in too, like the Open vSwitch, and we will drive from there to develop additional storage repositories and so on.  But the key emphasis is the use of XCP as a platform for the entire community, with a starting point, for which we have offered the code base of XenServer. 

Key partners such as VA Linux, Oracle, Novell, Fujitsu and Intel and AMD are all committed to the ongoing delivery of additional value to the platform, which will therefore have multiple routes to market, a strong ISV community and hopefully deliver revenue to a broad sector of the market.

Labels: Citrix, Xen

In 2007, when Citrix, one of Microsoft's strongest allies, acquired XenSource, a startup whose success depends on an open source product (the Xen hypervisor), nobody really believed the move would benefit the community in any way.

The major concerns were that, over time, Citrix would abandon the development of Xen to focus on a proprietary hypervisor, that Citrix could try to influence the Xen development to provide an indirect advantage to Microsoft and/or that Citrix could use its influence on the Xen project to damage all the competitors that were relying on it (at that time Virtual Iron, Novell, Red Hat, Sun and Oracle).

After the XenSource acquisition, some major vendors (Red Hat and IBM for example) and individual contributors lost interest in the Xen project and started to focus on KVM (IBM effort, Red Hat effort). Possibly because of this relationship between Citrix and Microsoft, possibly because Citrix has never been an open source champion.
Of course VMware did all its best to facilitate the exodus from the Xen project.

virtualization.info is unable to exactly track or measure the Citrix contributions to the Xen project since the XenSource acquisition, which made progresses in the last two years and has an impressive roadmap.
People more informed on this aspect are welcome to comment to the post with details.

For sure Citrix approached the open source world from different angles: it invested in the networking vendor Vyatta, which competes against Cisco an open source software router; it’s behind the development of the first open source virtual switch for virtual infrastructures, the Open Virtual Switch, and now it’s supporting the creation of an open source cloud computing platform, the Xen Cloud Platform (XCP).

Whatever the company has done so far, it was not enough to convince Linus Torvalds and the other Linux maintainers to include Xen in the kernel, side by side with KVM.
It seems like just a technical issue, but maybe it’s more than that.

The Citrix new move to the open source world is joining the Linux Foundation.

The official reason behind this move is to ensure that the Linux operating system works the best inside its XCP cloud and in the upcoming client hypervisor XenClient:

“The Linux Foundation provides a neutral forum for collaborative work on requirements for Linux and complementary projects such as the Xen Project, Xen Client hypervisor Initiative (XCI) and Xen Cloud Platform (XCP) initiative,” said Ian Pratt, founder and chair of Xen.org and vice president of Advanced Products at Citrix Systems. “Citrix has joined the Linux Foundation both in its role as leader of the Xen Project and because it ships commercial products based on Xen.”

In addition to developing the Xen hypervisor, the Xen community is working on the development of complete client hypervisor and cloud virtualization platform products, which incorporate Linux as an embedded, secure, optimized run time for the Virtual Machine Monitor. The Xen community also develops open source technology to permit Linux to run with optimal performance on other hypervisors, such as Microsoft Hyper-V and VMware ESX Server.

Anyway, it’s probably safe to speculate that more than anything else, Citrix wants to see Xen shipped out-of-the-box with every Linux distribution in the market. And becoming a Linux Foundation member may be the first step to achieve the task.

Labels: Alliances, Citrix, Xen

In June VMLogix announced the upcoming availability of a special version of its virtual lab automation product that could support Amazon EC2.

The product, dubbed LabManager Cloud Edition (CE), was released two weeks ago at VMworld 2009.

While the privacy and security concerns expressed in our previous coverage remain, it is true that VMLogix may be one of the first vendors to set the trend for the coming months: those customers that decide to embrace cloud computing may easily recognize the need for management consoles that extend the 3rd party IaaS architectures to achieve specific tasks such as virtual lab automation.

There are evident benefits:

The position of VMLogix as an acquisition target becomes more and more interesting.
Citrix, which already has an OEM agreement with them to distribute LabManager as part of Essential, for sure must be extremely pleased to see how VMLogix is proficient in manipulating Xen-based cloud computing facilities.

Labels: Amazon, Releases, Virtual Lab Automation, VMLogix, Xen

Earlier this week Amazon announced its Virtual Private Cloud (VPC) offering, a segmented version of its Xen-based Elastic Computing Cloud (EC2) that is accessible only through a VPN connection.

There were at least a couple of reasons to launch VPC right now: sure, it is the 3rd anniversary of EC2, but most of all it’s the week before VMworld, the VMware conference that this year is going to have a major focus on cloud computing.

Both Xen.org and VMware will in fact launch two new initiatives called Xen Cloud Platform (XCP) and VMware vCloud Express.

XCP will be a set of tools, of course distributed as open source, to extend the capability of the hypervisor as a cloud computing platform. And it will be supported by all the members of the Xen.org advisory board members, including Citrix, HP, Intel, Novell and Oracle.

So the Xen Cloud Platform will merge together new and existing pieces of software in a single package even if it’s not clear at the moment what will be part of the platform exactly.

For sure XCP will include support for the DMFT existing and upcoming standards: the OVF  to load virtual machines from any 3rd party hypervisor (Citrix, VMware, Microsoft, etc.) and to migrate them across federated clouds, and the upcoming VMAN interface.
The VMAN support alone won’t be enough to grant a seamless migration from a private virtual data center to a public or private XCP cloud, so it’s very likely that the platform will support some virtual machines live migration capabilities.

XCP will also integrate the just surfaced Open vSwitch, an open source virtual switch which offers features similar to the ones provided by the Cisco Nexus 1000V in VMware vSphere 4.0.

XCP will also feature some advanced storage capabilities that support multi-tenant cloud services, and this mean mean that Citrix will contribute the project by releasing a part of its StorageLink technology as open source.

The presence of standardized interfaces and open components means that any commercial offering could be able to interoperate, extend or manage the Xen Cloud Platform in a not-too-distant future.
And this includes existing clouds like Amazon EC2 or RackSpace Cloud Servers (formerly Mosso) as well as the products offered by any vendor, including VMware.

Of course it’s entirely expected that Citrix will launch a version of its Essential for XCP but we already know for sure that the Xen Cloud Platform will support open source management solutions like Eucalyptus (adopted at NASA) and OpenNebula.

The existence of VMware vCloud Express, was revealed by Forbes just two days ago.
Forbes describes it as a “an easy way to get up and running with vCloud service”, but the moment there are no other news about it.
VMware is expected to formally announce the product early next week.

Labels: Citrix, Cloud Computing, VMware, Xen

When VMware introduced its new cloud computing mantra one year ago, there were at least four reactions: hope, skepticism, irritation and confusion.

Some truly hoped that the data center could become as easy and ubiquitous as the power grid in just a couple of years, as VMware predicted.
Others expressed skepticism (include this site among them) about the chances that such revolution could happen in such short time frame and that it would be of any relevance for the SMBs.
Google got irritated because the new VMware CEO Paul Maritz started his new career by saying that the search giant approach to cloud computing is fundamentally wrong.
And others were just confused by the introduction of public and private clouds.

The public cloud VMware was talking about is an Infrastructure as a Service (IaaS) architecture, where virtual machines are provisioned on demand and the customers are billed on a pay-per-use model (it’s much more than that, but these are the two fundamental aspects that everybody keeps in mind).

But what is a private cloud exactly?
Is it a new way, cooler way to call the already cool enough data-center-in-a-box concept where hardware virtualization still is the fundamental piece? 
Or is it a cloud-in-a-cloud solution, where housing meets virtualization?
Or something even different?

Amazon, which offered a IaaS architecture based on Xen for two years, just offered its answer: it’s called Virtual Private Cloud (VPC) and it basically is a private segment within its popular Elastic Computing Cloud (EC2) facility, which customers reach through a VPN connection.

RightScale, an Amazon partner on this new evolution of EC2, gives some additional details on how this VPC can be configured by the customers.

VCP is available just as limited beta right now but it already is another huge milestone for Xen.
The more Amazon expands EC2 and attracts new customers the more companies will recognize in EC2 the “default” choice for public and private IaaS solutions, and the more credibility will be transferred to those virtualization vendors that are using Xen: Citrix and Oracle.

VMware knows that and this is why it is investing in Terremark and why it is acquiring SprintSource: VMware has to build something that can rival with Amazon EC2 if it wants to keep up the perception that vSphere is cloud-ready.

Labels: Amazon, Xen

In May, during its main conference Synergy, Citrix announced the existence of an open source virtual switch that may compete with the Nexus 1000V that Cisco made available for VMware vSphere.

In early June, the Citrix CTO Simon Crosby shared a very few details about it, but so far most of the virtualization community doesn’t know much about it. But the official website about the project quietly appeared online now: the product is called Open vSwitch and is released under the Apache 2 open source license.

The first release (which is almost complete and available online as well) is designed to support distributed networking (like the Cisco Nexus 1000V) and includes the following features:

• Visibility into inter-VM communication via NetFlow, SPAN, and RSPAN
• Standard 802.1Q VLAN model with trunking
• Per VM policing
• NIC bonding with source-MAC load balancing
• Kernel-based forwarding
• Support for OpenFlow
• Compatibility layer for the Linux bridging code
  (The Open vSwitch can be even used inside a plain Linux distribution in place of operating system bridge)

On top of that the following features are part of the roadmap:

• User-space forwarding engine
• sFlow
• Compatibility layer for VDE
• Ethernet over GRE (for ERSPAN and virtual private network creation)
• Full L3 support + NAT
• Priority-based QoS
• More management interfaces (IOS-like CLI, SNMP, NetFlow)
• 802.1x/RADIUS
• Support for hardware acceleration (VMDQ, switching chips on SR-IOV NICs)

The version available online is near the 1.0 (0.90.4), but it’s only available as source code.
The online documentation already explains how to use it with a XenServer 5.5 host.

Labels: Citrix, KVM, Xen

In June Xen reached version 3.4 introducing out-of-the-box support for Hyper-V and a series of enhancements that will make the platform a good client hypervisor.

At the beginning of this month Xen further progressed to version 3.4.1, which is just a maintenance release, but the truly interesting things are in the Xen 4.0 roadmap (with our emphasis):

• RDMA Live Migration Support
• Dom0 kernel in Linux 2.6.30 or later
• Dom0 support for Marvell 6480 disk driver
• Pass through USB-Controllers/Devices for PV Guests
• Fault Tolerance - Project Remus and/or Kemari
• Monitor, Limit, Control network traffic coming at DomUs
• Internationalization / Unicode Support
• Configure Virtual Bridge like Real Switch (e.g. Control VLAN, port status)
• VLan tagging per NIC in the VM Config File
• Virtual Ethernet Switch
• Physical Xen boot/install support via native UEFI (pUEFI) and virtual UEFI (vUEFI) support
• Limit I/O for individual disks of VM (similar to credit scheduler weight)
• Dynamic Memory Management for Overcommiting RAM
• PCI CGA Passthrough for VT-d (vendor cards like Nvidia, AIT, etc)
• Full AMD IOMMU Support
• Online resizing of DomU Disks
• Cross compliling Xen and Modular Builds

On top of this very interesting list, Ian Pratt, the Xen CTO (and Xen.org Chairman and XenSource Founder and Citrix Vice President of Advanced Products), informally indicated a few areas where contributors are welcome. And in this list there’s a lot of precious details there (our emphasis again):

• Xen will soon be including the openflow vswitch developed under the openvswitch.org project. In order to integrate support for SR-IOV network hardware, we need a special kind of bond driver in the guest that initially routes traffic via the vswitch, but then can receive instructions from the vswitch to route individual flows to the direct hardware path (falling back to the normal software path via the vswitch if the SR-IOV VF gets unplugged).
• Build on some of the existing work done in Cambridge to use Tungsten Graphics Gallium as a device-independent and API-independent 3D remoting protocol.
• Get the blkback/netback drivers working in a HVM guest, effectively allowing domain0 to optionally be a HVM guest.
• Fully implement domain0 restartability, effectively enabling a dom0 reboot or upgrade without rebooting the rest of the system. (There’s been plenty of work done on this already, but it needs finishing off)
• investigate how a hypervisor could best use large amount of NAND FLASH memory. (not just via a disk API, but as native FLASH)
• Deterministic replay for xen. (see the University of Michigan papers).
• work on the ARM xen port to get it to the same level as the x86 port
• implement UBC Remus for HVM guests and integrate it into the main Xen tree.
• virtualize a GPU in a device-dependent fashion (everyone has been doing it in a device-independent fashion, but there may be big performance and fidelity wins to be had doing it in a device-specific fashion). Since the Intel GPU drivers are open source it should be possible to do this on Intel GPUs.
• Extend Cambridge/UBC Parallax to implement content-addressable hashing to save disk space
• Switch the PV SCSI over to using the netchannel2 ring protocol for improved performance.

Only three major virtualization vendors are currently relying on Xen: Citrix, Oracle and Novell.
Each one will try to innovate with enterprise-grade capabilities to be added on top of this “basic” feature-set.
Customers can can now have a better idea of where the three companies are going. The only problem is that none of them is probably ready to share some release dates for some or all the features above.

Labels: Releases, Xen

For a long time a number of contributors sponsored by Red Hat worked on a virtualization interface that could standardize the way hypervisors are managed, getting rid of the differences between vendors’ implementations.

The API is called libvirt and it’s around since early 2006.

Red Hat has a strong commitment on it, at the point that its imminent KVM-based virtualization offering is based on its, as announced in June 2008.
This is why the API is released under the GNU Lesser General Public License (LGPL) which allows the inclusion in any commercial product.

Through libvirt, a management platform running on Linux, Solaris, Mac OS or even Windows can already control both Xen, KVM, Sun VirtualBox, Parallels OpenVZ, QEMU, LXC and User Mode Linux (UML). But the best has yet to come.

The just released version 0.7.0 includes a number of remarkable new features, including support for the IBM POWER hypervisor and what seems a first attempt to support VMware ESX.

Of course this doesn’t mean that VMware will allow a product using libvirt to manage its flagship hypervisor without buying vCenter Server.
But for sure it means that in a near future Red Hat may be able to offer what Microsoft already offer with System Center Virtual Machine Manager (SCVMM): the capability to control multiple hypervisors through a single management console. And this may be extremely appealing for some of those customers that already purchased vCenter.

Labels: KVM, Red Hat, VMware, Xen

Xen.org recently published a revamped edition of its official training slide deck titled Introduction to the Open Source Xen Hypervisor, available under the Creative Commons Attribution-Share Alike 2.0 Generic License.

Unfortunately the 154 slides don’t have footnotes and there’s no audio, but it’s still a welcome effort to simplify the evangelization of the hypervisor that powers half the virtualization platforms available on the market (Citrix XenServer and Oracle VM Server/Virtual Iron).

Labels: Training, Xen

Oracle continues to stay mum about its integration plan for Oracle VM, Sun xVM Server and Virtual Iron hypervisors, but don’t hold anything when it’s time to talk about the new competitors.

Just two months ago the company dismissed the VMware virtual appliance initiative and its Marketplace, saying that it doesn’t contain anything but toy appliances.
One month later Oracle decided to clarify how the word co-opetition is not in its vocabulary, modifying the support policy to exclude every virtualization vendor that offer a hypervisor for x86/x64 architectures.

Today it’s time to hit Red Hat (and by some degrees Novell).
On its corporate blog last week Oracle highlighted its commitment to Xen and the open source:

…Oracle's Linux commitment began in 1998 with the first commercial database on Linux. Not only does Oracle run the whole business on Linux, but also run the base development on Linux for all our products. Today Oracle has over 9,000 developers working on Linux and provides Global Linux Support in over 100 countries…

The key point of this apparently candid post is about the quality of support that only Oracle can offer.
To support the statement Oracle points to another article about the reasons behind the launch of Oracle Unbreakable Linux:

Oracle Unbreakable Linux launched two years ago as a support program for existing Red Hat Enterprise Linux (RHEL) implementations or for new Oracle Enterprise Linux implementations. Oracle Unbreakable Linux program is about enterprise-class support that customers can't get (or is not available) from Red Hat.

…

Oracle brings the highest support quality, more value, and proven business practices to Linux support, including the following items Red Hat can't:

• 7500+ professionals providing 24x7, global support in over 145 countries
• Lifetime support policy (7+ years of general product support with the ability to extend to unlimited number of years)
• Premier backporting (Request backport of specific features eliminating pressure to upgrade with every update release)

…Due to dissatisfaction with Red Hat's quality of support as well as a desire to get more value, many users have switched from Red Hat Support to Oracle Unbreakable Linux Support…

The message is specifically directed to Red Hat because Red Hat is the company that promoted Xen for years and then decided a complete U turn by replacing the open source hypervisor with KVM.

Red Hat will (re)start competing with the other virtualization players in September when its new offering will become finally available.
And before any customer even think about jumping on the KVM bandwagon, Oracle wants to make sure that everybody knows how much better they are at support.

Labels: KVM, Oracle, Red Hat, Xen

Yes, Oracle is slowly increasing the frequency of its incursions in the virtualization world.
Now that the company controls three hypervisors (its own Oracle VM, Sun xVM Server and Virtual Iron) it’s expected that a master plan comes out sooner or later.

For now Oracle just shows a little piece of it, by announcing its paravirtualized (PV) drivers for Windows guest OSes.

Oracle offers them for Windows Server 2003 and 2008 as well as for Windows XP and Vista. For each one there’s a 32bit and a 64bit version. Of course they are only available for the Oracle VM hypervisor.

The paravirtualized drivers improves the performance of virtual machines when there’s no chance to leverage the capabilities of hardware-assisted virtualization technologies like AMD-V RVI (available in the Quad-Core Opteron CPUs since September 2007) and Intel EPT (available in the new Xeon 5500 CPUs).

While enhancing the performance of Windows guest OSes, the PV drivers that Oracle is shipping also imply some limitations: once installed them, the virtual machines state can’t be saved and restore anymore and live migration is no more available.

It’s interesting to note how different is the current Oracle approach compared to the one of its new subsidiary Virtual Iron.
Exactly three years ago Virtual Iron announced its intention to stop the development of PV drivers:

…Paravirtualization requires substantial engineering efforts in modifying and maintaining an operating system. However, these heroic efforts are inevitably losing the battle against Moore's Law and hardware advances being made in the x86 space. By the time the first product with paravirtualization appears on the market, more than 80% of the shipping x86 server processors from Intel and AMD will have hardware-based virtualization acceleration integrated into the chips (Intel-VT and AMD-V or "Rev-F"). This hardware-based acceleration is designed to optimize pure virtualization performance, primarily the virtualization of CPU, and it renders OS paravirtualization efforts as completely unnecessary and behind the technology curve…

Update: As some comments below highlighted, the last point in this article, about the divergence of opinions between Oracle and Virtual Iron on paravirtualization is wrong.

In 2006 Virtual Iron was rejecting the idea of running fully paravirtualized guest OSes (which requires kernel patching). 
Oracle is not taking a different approach. It’s just releasing paravirtualized drivers to speed the I/O operations, something that all the other virtualization vendors do as well through guest OS packages that customers are recommended to install (like the VMware Tools).

Labels: Oracle, Xen

The Xen.org community and Citrix are arranging an interesting event for late June in Berlin called Xen Direction Europe 2009.

Compared to the well-known Xen Summits, this seems easier to understand for somebody that is not a Xen hacker (read: it contains more marketing material) but no less interesting as the agenda includes some presentations that are probably worth the visit like:

• Virtualization - it's not just for servers anymore Intel
• Highly available virtual infrastructures based on Xen Lufthansa Systems
• HXEN: Hosted Xen Hypervisor Project Citrix

Of course the last one is especially interesting as it will cover the progress of the new hosted VMM architecture that will power a Citrix product called XenWorkstation, at least accordingly to the virtualization.info sources.

One session promises to be very funny (underline is ours):
Virtualization of mission-critical deployments Oracle with Xen: Oracle users choose Oracle VM
Like the Oracle users have a real chance.

Labels: Citrix, Events, Xen

It doesn’t matter if we are talking about SaaS, PaaS or IaaS architectures. Customers have many reasons to not trust the cloud computing solutions that the market offers today and one of them is the lack of security.

Amazon has the oldest, most popular and very likely the largest cloud infrastructure existing today, and thus it must under continuous fire when enterprise customers evaluate its Xen-based Elastic Computing Cloud (EC2).

The company recently announced a series of initiatives to make EC2, S3 and the other Amazon Web Services (AWS) facilities more secure, and to clarify the level of security currently in place:

• Certifications and Accreditations
  AWS is actively seeking the appropriate security certifications and accreditations in order to provide our customers with additional confidence in our infrastructure. In addition, we will continue to publish guidance on how AWS enables customers to build applications that are compliant with standards, such as HIPAA.
• Physical Security
  Amazon has many years of experience in designing, constructing, and operating large-scale data centers. AWS infrastructure is housed in Amazon-controlled data centers throughout the world. Only those within Amazon who have a legitimate business need to have such information know the actual location of these data centers, and the data centers themselves are secured with a variety of physical barriers to prevent unauthorized access.
• Secure Services
  Each of the services within the AWS cloud is architected to be secure and contains a number of capabilities that restrict unauthorized access or usage without sacrificing the flexibility that customers demand. For more information about the security capabilities of each service in the AWS cloud, consult the Amazon Web Services: Overview of Security Processes whitepaper.
• Data Privacy
  AWS enables users to encrypt their personal or business data within the AWS cloud and publishes backup and redundancy procedures for services so that customers can gain greater understanding of how their data flows throughout AWS. For more information on the data privacy and backup procedures for each service in the AWS cloud, consult the Amazon Web Services: Overview of Security Processes whitepaper.

We’ll see if the effort will produce a security compliant cloud computing infrastructure that enterprise customers can trust. Possibly before the end of the next decade.

Labels: Amazon, Xen

One of the oldest (and hottest) topic in the history of modern virtualization is if the Xen open source hypervisor can be integrated into the Linux kernel or not.

XenSource tried to achieve the goal for years (while VMware did its best to avoid it), but in December 2006 Linus Torvalds announced the decision to include another virtualization platform in place of Xen: KVM.

KVM was developed and maintained by the startup Qumranet, acquired by Red Hat in September 2008, and at that time was just 6 months old, much less mature than Xen.
Despite that and because of its architecture (at least this is the official reason), KVM has been included in the kernel since version 2.6.20 and Xen is not.

After this and after the acquisition of XenSource by Citrix, the idea of Xen inside Linux seemed definitively archived. But the community is still debating about the topic.

Torvalds’ comment on the idea is lapidary:

…If Xen was a single driver thing, we wouldn't have this discussion. But as is, Xen craps all over OTHER PEOPLES CODE. When those people then aren't interested in Xen, why is anybody surprised that people aren't excited?

Thanks to c0t0d0s0 for the news.

Labels: KVM, Xen

The open source Xen hypervisor reaches version 3.4 after almost one year of development.

This is an important milestone for the project because of the key features introduced:

• Xen Client Initiative (XCI) Enhancements
  Xen 3.4 contains the initial XCI code release providing a base client hypervisor for the community to extend and improve.
  Simon Crosby, CTO of Virtualization and Management division at Citrix, adds a pretty interesting detail to this point:
  For the first time the Xen project is moving away from providing simply the hypervisor, and leaving it to vendors/users/developers to build their own system.  This release contains the whole enchilada, including Dom0, the management tool stack and Xen.  In other words, everything you need to be up and running with a Xen client system.
• Reliability – Availability - Serviceability (RAS)
  Xen 3.4 delivers a collection of features designed to avoid and detect system failures, provide maximum uptime by isolating system faults, and provide system failure notices to administrators to properly service the hardware/software. The combination of these services provide for a robust Xen hypervisor with fault-tolerant and back-up capabilities built-in.
• Power Management
  Xen 3.4 improves the power saving features with a host of new algorithms to better manage the processor including schedulers and timers optimized for peak power savings.
• Support for the Hyper-V enlightenment interface

The XCI components are critical for all those vendors that are working to offer a client hypervisor (including Citrix, Phoenix Technologies, Virtual Computer and Neocleus) but of course the most interesting new feature is the out-of-the-box support for the closed-source brother of Xen, Hyper-V.

From now on it will be specially interesting to see how the Xen roadmap evolves, considering that only three major players are using the hypervisor: Citrix, Novell and Oracle (which now includes both Sun and Virtual Iron).

Labels: Microsoft, Xen

It doesn’t matter if you are a loyal customer of VMware, Citrix or Microsoft. Anytime one of these three vendors (or any other in the market) mentions its effort in the cloud computing space using virtualization the comparison term is Amazon.

Amazon has been the first to develop a general purpose cloud computing infrastructure and offer it to the general public. The company launched the (beta) service in August 2006, adopting the open source hypervisor Xen as virtualization engine of choice.
So far their Elastic Computing Cloud (EC2) is the biggest and most mature Infrastructure-as-a-Service (IaaS) architecture existing on the market.

During the last three years Citrix acquired XenSource, the leading company for the Xen project, and released the commercial implementation of Xen, XenServer, free of charge.
Amazon doesn’t reveal anything about its Xen implementation, but it’s same to assume that the company engineers had to develop a lot of tools and features on top of Xen.
Now the company can have for free enterprise management, virtual machines live migration, resource sharing, integrated storage management and, at the same time, can count on the enterprise support that Citrix now offers.
This must be a tempting proposition to lower the EC2 maintenance costs.

If, in the future, Amazon wants to use EC2 to develop massive virtual desktop infrastructures (VDI) and offer hosted desktops in the consumer market, Citrix is ready, as they are about to release a client hypervisor based on Xen, XenClient, for free as well.

So how long before Amazon moves from Xen to XenServer on EC2?

Maybe not so much: last week at the Synergy conference (which co-hosted the virtualization.info’s Virtualization Congress 2009) Citrix announced a new partnership with Amazon to offer and support part of its products on the EC2 virtual machines.

As Richard Jones, VP of Data Center Strategies at Burton Group, said on his corporate blog:

The announcement on May 6th at Synergy of Citrix-Amazon collaboration on internal/external cloud interoperability has “we’re moving to Citrix XenServer as our EC2 hypervisor infrastructure” written all over it.

Labels: Amazon, Citrix, Xen

Earlier this week SDTimes published a brief coverage of the Linux Foundation’s Collaboration Summit, which was held in San Francisco last week.

A very brief note in the article highlights a remarkable information:

For the virtualization crowd, Zemlin [Jim Zemlin, Executive Director at the Linux Foundation] said that, moving forward, the Linux Foundation is encouraging vendors and developers to standardize on KVM, not Xen.

If true this may be the confirmation that the Citrix acquisition of XenServer has compromised the relation with the open source community, despite Citrix is giving back.

It’s interesting to note that the Red Hat acquisition of Qumranet, which developed and maintains KVM, didn’t have the same impact.

Labels: KVM, Xen

In early March virtualization.info broke the news that Citrix was about to release a hosted version (aka type-2 virtual machine monitor) of of XenServer, called XenWorkstation, that could compete with VMware Workstation, Parallels Workstation, Microsoft Virtual PC, VirtualBox and so on.

There are good reasons for Citrix to do so, and the impressive number of visits we received on that article confirms a great interest about such product.

XenWorkstation was not launched the week of March 9 as we speculated.
While some people (including ones that claim to be Citrix employees) reported that this product doesn’t exist, our sources tells us that Citrix decided to postpone its launch.

True or not (virtualization.info long time readers know that our sources are very reliable), Citrix just released to the Xen community the open source code of a type-2 VMM version of Xen, currently called KXen.

The virtualization platform supports Windows XP, Vista and Windows 7 (all 32bit) as host OSes.
64bit of these Windows versions will be supported soon, as well as Mac OS X.

Please note that the KXen code is a snapshot of the Xen code base used in XenServer today.
Future versions of this product will be based on Xen 3.4 and following.

The code is available here: Windows version / Linux version.

Labels: Citrix, Xen

In 2006 the ConVirt team started an ambitious project: develop an open source, multi-host management console for Xen.
Initially called XenMan, the tool was then renamed ConVirt and its roadmap was enriched with several highly desirable features.

Three years later the ConVirt team morphs in a company called Convirture, and ConVirt, still an open source product, finally reached version 1.0 with a notable number of features:

• Support for Xen and KVM
• Support for multi-host virtual infrastructures
• Support for virtual machines snapshot, live migration, backup and decommission
• Support for VMs templates and virtual appliances
• Support for storage usage

The product is available free of charge here.

Labels: Convirture, KVM, Xen

Normally virtualization.info doesn’t cover customers case histories but in this case we’ll make an exception.

SAP as a software is one of the most important mission-critical applications in the world.
SAP as a company is one of the savviest companies in the industry about virtualization: during 2007, the company fully embraced hardware virtualization, supporting VMware, Xen (both Novell and Red Hat implementations) and Microsoft Hyper-V platforms.
They even have a 3-days conference called Virtualization Week.
But most of all SAP is one of the key partner of VMware as the company demonstrated at the recent VMworld Europe 2009, when Paul Maritz granted SAP no less than 30 minutes of his opening keynote.

The fact that SAP is virtualizing around 500 servers with XenServer is remarkable.
It really validates the Citrix hypervisor.

To be fair the press announcement specifically say that XenServer will be used to virtualize the worldwide training centers first and the project management division later, which will P2V migrate hundred of dev/test/support machines.
So SAP is not yet ready to use XenServer for the production environment (or maybe they are but cannot).

Anyway, VMware representatives sometimes say that XenServer is not an enterprise-grade hypervisor. Now they’ll have to explain why one of their best and most trusted partner is going to adopts it so widely.
Is it the price to blame? Or is it that they are overlooking the competition?

Labels: Citrix, SAP, Xen

While a new startup works to unofficially open source the VMware VMFS, Citrix has officially open sourced its implementation of the Microsoft VHD format.

Citrix and Microsoft adopt the same virtual hard drive format since September 2007, when they closed a deal to adopt VHD in all the upcoming products.

In over two years Citrix has developed an optimized implementation of the product and it’s now giving it back to the open source world by submitting its code to the Xen community for inclusion in the hypervisor code base under the BSD license.

If approved, Citrix partners and competitors that adopt Xen (like Virtual Iron, Oracle, Sun, etc.) will be able to use it side by side with QEMU Copy-On-Write (QCOW).

Labels: Citrix, Microsoft, Xen

By now it should be clear that Citrix will do everything possible to keep its leadership in the application virtualization space and increase its relevance in the hardware virtualization space.

The first step was giving away XenServer (with Live Migration, Resource Pools and much more) for free.

The second step will be releasing a free virtualization platform for the desktops: XenWorkstation.

Please note that this has nothing to do with the client hypervisor that Citrix is developing with Intel.
This is a type-2 version (or hosted VMM) of Xen that will run on consumer hardware, exactly like VMware Player/Workstation/Fusion, Parallels Workstation/Desktop, Sun VirtualBox or Microsoft Virtual PC.
And Citrix may release it as soon as next week according to virtualization.info sources.

Xen will run as a kernel module and will be available for Windows and Mac OS X hosts.

A part of the VMware early success depend on Workstation: the product is so good that spread across the world and crawled into the biggest corporations without passing through long enterprise sale.
System and software engineers introduces the culture of VMware inside their companies using Workstation on daily basis for simple tasks: testing a new product or OS, developing code, separating the private and the business workspace, etc.

Citrix badly need to build a reputation in the virtualization community. And a free XenWorkstation may be another good way to do so.

Labels: Citrix, Xen

While virtualization professionals are still trying to figure out how the renewed alliance between Microsoft and EMC will work on virtualization, another major event happens: Red Hat joins the Microsoft Server Virtualization Validation Program (SVVP).

Pretty much like Cisco (why Cisco is here?), Citrix, Novell, Oracle, Sun, Unisys (why Unisys is here?), Virtual Iron and VMware did in the last few months (the SVVP was launched in June 2008) now also Red Hat had to accept the Microsoft conditions to offer concrete Windows support to its virtualized customers.
As side benefit, the Microsoft customers finally will be able to run Red Hat guest OSes on their Hyper-V hosts.

The agreement implies that:

• Red Hat will validate Windows Server 2003 SP2, Windows 2000 Server SP42, and Windows Server 2008 guests on Red Hat Enterprise virtualization technologies
• Microsoft will validate Red Hat Enterprise Linux 5.2 and 5.3 guests on Windows Server 2008 Hyper-V (all editions) and Microsoft Hyper-V Server 2008

Note that, as usual, Red Hat is not specifying which virtualization technology will be validated. As their new offering based on KVM is not ready yet, we may safely assume that this agreement is about the implementation of Xen currently part of Enterprise Linux (RHEL).

Labels: Microsoft, Red Hat, Xen

While waiting to replace Xen with KVM somewhere in H1 2009, Red Hat continues to improve its current virtualization platform.

In the new Enterprise Linux (RHEL) 5.3, released this week, the company greatly extended the supported Xen limits:

• from 8 to 32 vCPUs
• from 64GB to 80GB vRAM
• from 32 to 126 pCPUs
• from 64GB to 1TB pRAM

Additionally the Xen included in RHEL 5.3 supports the Intel nested paging tables technology EPT featured inside the new Intel Core i7 (codename Nehalem) processors.

Labels: Red Hat, Xen

In October 2008 Amazon finally declared its Xen-based Elastic Compute Cloud (EC2) ready for production, introducing a Service Level Agreement, the availability for 32 and 64bit Windows Server 2003 virtual machines, and the support for IIS and SQL Server inside each guest OS.

At that time the company also hinted at a new management console that customers could use to manage their virtual infrastructure in the cloud, but the product remained unveiled until last week.

Simply dubbed Web-based AWS Management Console, the product is a feature-rich control panel that allows to create, launch, find and manage virtual machines (called Amazon Machine Images or AMIs), create and manage volumes and snapshots (called Elastic Block Store or EBS), and even manage the security permissions and the firewall settings.

The product is still in beta but its AJAX interface seems pretty valid and Amazon seems to have created an interface even better than the popular Elasticfox extension for Firefox:

Amazon published a nice webcast about the new console here.

Labels: Amazon, Xen

In November 2007 Oracle decided to enter the virtualization market and announced its own platform: Oracle VM.
The product is based on the open source hypervisor Xen, it’s offered free of charge, and features an enterprise management console called Oracle VM Manager.

So far the product was mainly pushed to those customers that were virtualizing Oracle Database on other platforms (read VMware) so that many potential customers didn’t even notice its presence or didn’t take the offering too seriously.
But the reality is that the company bills Oracle VM as a general purpose hypervisor that supports for many different workloads.

Now Oracle is taking further steps to demonstrate how serious it is in the virtualization market: last week it joined the Xen Advisory Board.

The move has a double effect: on one side it highlights a real commitment to improve the product, on the other it clarifies that there’s no intention to move to KVM.
Somebody in fact speculated that Oracle may want to switch to KVM because its Unbreakable Linux derives from Red Hat Enterprise Linux (RHEL) and Red Hat is dropping Xen in favor of KVM.

The Oracle appointee is Wim Coekaerts, exactly the man behind Unbreakable Linux.
With him Oracle will send Dan Magenheimer, the leader of the Xen port on Intel Itanium architecture.

Labels: Oracle, Xen

At the recent Xen Summit 2008 in Tokyo a specially interesting project finally reached version 1.0: Kemari.
The project was presented for the first time in April 2007 but only now it reaches a version stable enough to be marked as GA.

Developed by Yoshiaki Tamura, Kemari is a patch for Xen 3.3 that brings host fail-over.
It works with both Linux and Windows guests OSes.

A briefly description tells enough to understand how it works:

Kemari in VMM taps event channel, pauses the guest (not suspend), prepares for transfer, and Kemari in userland transfers the guest. On failover, Kemari on the secondary restores the guest, and the backend drivers in dom0 set up the backend rings from the state of the shared rings in the guest

Here a video where a Windows XP virtual machines survives the shut down of one node in a hardware cluster of two:

The exiting news is that Kemari is now part of the Xen roadmap, and this means that the open source hypervisor may offer out-of-the-box fault tolerance as soon as it hits version 3.4.
Citrix will be probably very happy. We wonder if Marathon Technologies will be happy as well.

Labels: Tools, Xen

Starting November 2007, we had signs that multiple entities (virtualization vendors, phone vendors, embedded CPU vendors) are working to bring hardware virtualization to mobile devices like cell phones and PDAs.

The fact that Samsung is porting Xen on the ARM processor should be more than enough. If not here another confirmation.

The CTO of Xen and Vice President of Advanced Products at Citrix and Chairman of Xen.org, Ian Pratt, gave an interview to CNET yesterday and said:

Q: As vice president for advanced products, what are you looking at?
A: Client virtualization is an area I'm spending time on. It's an area where Xen leads--despite some bluster from VMware. It's an area where we can make a difference, and it will be driven by application delivery.

There will be virtualized smartphones on the market in the not-too-distant future. ARM has built virtualization into its processors; they didn't put that in for fun.

Virtualization in the embedded market will follow a similar playbook to virtualization in the x86 market. Client virtualization is going to happen quite quickly. It won't go through the phase where users have to choose their virtualization solution, because virtualization won't exist as a category. It will be part of the device when you buy it…

Labels: Citrix, Xen

While Sun puts the final touches to its first hypervisor xVM Server 1.0 and to xVM Ops Center 2.0 (which could be released in November), some more details about the products emerge from a corporate blogs.

In a list of FAQs published there an interesting (yet confusing) indication about the free vs paid strategy about the xVM family:

Q: Within the Sun xVM Portfolio, what's going to be open-source, and what will cost money?
A: Sun xVM VirtualBox and Sun xVM Server will be open-sourced. Some features, though, such as guest migration, are part of Sun xVM Ops Center. Also, service contracts can be purchased for any part of the Sun xVM Portfolio.

The list also includes some additional details about the supported virtual machines formats:

Q: Will Sun xVM Server support native Xen formats?
A: We don't, as there weren't a lot of requests for it.

Q: Can you move guests back and forth between Sun xVM Server and similar VMware solutions?
A: It's only one-way. Sun xVM Server can read vmdk files, but it doesn't save to the vmdk format, so you couldn't modify the guest and then move it back. As far as I know, VMware doesn't support our format either.

Labels: Sun, VMware, Xen

Today is a special day for Amazon: the company just declared its cloud computing infrastructure based on Xen, Elastic Compute Cloud (EC2), as ready for production and introduced a Service Level Agreement (SLA).

Each account will be allowed to configure up to 20 virtual machines with option to have more.
To manage the whole virtual infrastructure Amazon is also introducing a new web management console.

More than that EC2 finally offers 32bit and 64bit Windows Server 2003 virtual machines, reachable through RDP, despite this new option is considered as part of a new beta program.

On top of Windows, Amazon also supports Authentication Services (for more than five accounts or for LDAP connection), IIS6 (including ASP.NET) and 64bit Microsoft SQL Server (Standard Edition only) but the company doesn’t clarify which version is offered.

The lack of Windows XP or Vista as supported virtual machines means that Amazon is not ready to offer on-demand VDI yet. But this first beta program certainly is the first step in that direction.

Even without a desktop OS, the potential of Windows-based cloud computing is enormous.
Now Amazon has the unique opportunity to demonstrate that Xen can be as reliable as VMware ESX in hosting Windows VMs in the largest infrastructure on the planet.

VMware, Microsoft, Citrix, Virtual Iron, Red Hat, Novell, Oracle, Sun and the whole Xen community will look at EC2 much carefully now.

Rackspace, which is building something similar to EC2, will have to work a lot to generate the same kind of interest.

Labels: Amazon, Xen

Last month at VMword 2008 VMware announced its new vision all about cloud computing.
It seems clear that VMware wants a piece of the cloud computing business that Amazon built all alone with its Elastic Compute Cloud (EC2).

We’ll see if VMware aims at building something like EC2, very unlikely indeed, or if the major goal is just to replace the Xen virtual machines in EC2 with the ESX ones.

In any case VMware is not the only one that wants to attend this party: RackSpace, the huge US hosting provider that launched its IPO in August and that it’s papering the web with advertising, just acquired Slicehost, a small hosting provider that uses exclusively Xen virtual machines as on-demand virtual private servers for its 15,000 customers.

Also RackSpace offers virtual machine based VPS using VMware Infrastructure but so far the company never mentioned the product as part of a cloud computing strategy. With Slicehost it’s different:

Cloud Servers -- This new hosting solution, which will deliver on-demand server capacity to businesses of all sizes, will leverage key technology developed by Slicehost, which uses Xen virtualization software. Slicehost will remain as the company's developer brand, creating innovative new features driven through shared intellectual property in conjunction with development initiatives from Rackspace. As part of the announcement, Slicehost also announced new, larger slices for high performance computing, lower prices as well as IP sharing for high availability computing.

Just like Amazon, Slicehost only offers Linux as guest OS for its slices. So now that RackSpace entered the space, Amazon has one more reason to introduce the much awaited Windows guest OSes.

Who’ll be the first to offer hosted VDI?

Labels: Amazon, Rackspace, VMware, Xen

It may be just a coincidence but the just released Fedora 10 doesn’t include Xen. And this happens just a month after Red Hat unveiled its new virtualization strategy, adopting KVM and acquiring the startup that maintains it: Qumranet.

The reason behind this unexpected drop is explained in the official project newsletter:

No Dom0 Support in Fedora 10

…”There is pretty much zero chance that Fedora 10 will include a Xen Dom0 host. While upstream Xen developers are making good progress on porting Dom0 to paravirt_ops, there is simply too little time for this to be ready for Fedora 10. So if you need to use Fedora 10 as a host, then KVM is your only viable option at this time. If you can wait for Fedora 11 (or use RHEL-5 / CentOS-5) then Xen may be an option for you." …

The distribution lifecycle implies a new major release every six months on average.
This means that Fedora users will have a long time to explore the opportunities that KVM offers. And in the meanwhile Red Hat will be able to further attract them with some new interesting products based on Qumranet technology.

Thanks to Mike DiPetrillo for the news.

Labels: KVM, Qumranet, Red Hat, Xen

Amazon launched a virtual infrastructure available on demand and powered by the Xen hypervisor, the Elastic Computing Cloud (EC2), in August 2006.

As far as we know the number of customers that are currently using it is not public, but, despite early security issues and multiple outages, reliable sources reported to virtualization.info that such number is remarkable.
Nonetheless Amazon may have many more customers if it would start offering Windows virtual machines.

So far in fact the company only offers Linux instances. It’s unclear if this depends on technical issues (like the version of Xen that it’s currently in use), on policy issues (like the feeling that EC2 is not robust enough to support million of customers hosting Windows) or licensing issues (Microsoft has to give its blessing for such a massive infrastructure).

It seems that the things are finally changing: with a brief note online Amazon announced that EC2 will have Windows instances this fall.

At the moment the page just offers a notification alert subscription but, interestingly enough, it surveys the readers about possible uses of Windows virtual machines:

• Web Server
• Video Transcoding
• MS SQL Server Database
• Desktop Software
• Microsoft Software
• Backoffice Software
• Development
• High Performance Computing

Of course one of the most interesting options above, and there’s no guarantee that Amazon will allow that kind of use, is for desktop software. And that means that EC2 could become the biggest hosted VDI infrastructure on the planet (Brian Madden posted some interesting questions about this scenario).

Now, considering that Citrix influences the Xen community and that VDI is its main battleground against VMware, it would be interesting to know what kind of involvement it has in the whole project.

It would also be interesting to know if the startup Desktone has some involvement as well: the company is the first currently offering a technology for hosted VDI scenarios (see the virtualization.info coverage here) and, what a coincidence, is partially funded by Citrix.

Labels: Amazon, Citrix, Xen

Xen 3.3 has been just released and Xen.org already publishes the roadmap for the next version of the open source hypervisor.

The document reveals a major focus on desktop deployment, with multiple major enhancements to make Xen a great client hypervisor:

• Client device virtualization (e.g. battery status etc)
• GPU virtualization with Gallium
• USB 2.0 support, PV USB support
• Trusted HID
• Simple VGA/text-mode management console

Probably, the most important entry in the list above is the display card (GPU) virtualization, one of the most complex task to achieve in hardware virtualization.

As reported by Wikipedia:

Gallium3D is a software library for 3D graphics acceleration being developed by Tungsten Graphics, an engineering company with expertise in Linux and open-source graphics technologies. Gallium 3D operates between the graphics API and the operating system with the primary goal of making driver development easier, bundling otherwise duplicated code of several different drivers at a single point.

…

Gallium3D provides a unified API exposing standard hardware functions such as shader units found on modern hardware. Thus, 3D APIs such as OpenGL 1.x/2.x, OpenGL 3.x, OpenVG, GPGPU infrastructure or even Direct3D (as found in the Wine compatibility layer) will need only a single back-end, called state tracker, targeting Gallium3D API…

To allow a full GPU virtualization, display cards vendors (Intel, AMD/ATI and nVidia mainly) will have to support the technology.
The current status reported is not exactly encouraging:

The first implemented and already partially working drivers are Cell and Intel GPU drivers. Work is done on ATI Radeon cards providing a skeleton driver, and the Nouveau team is moving development to Gallium3D, including a solution for older fixed function nVidia cards which lack programmable shaders.

Several companies are currently working to make Xen a client hypervisor: the BIOS leader Phoenix Technologies (with its HyperCore), the just-launched startup Neocleus, and several major OEMs like Dell, HP and Lenovo.

If Xen 3.4 will really develop the features above these companies may get major benefits from it and push for an early implementation in their commercial products.

The upcoming new version anyway is not just about desktops. It includes an impressive range of additional features, including:

• full support for Intel VT-c (VMDq and SR-IOV)
• full support for OVF
• Virtual machine synchronization for fault tolerance
• SATA command virtualization

Labels: Xen

The capability to overcommit memory is something that VMware offers on its hypervisor ESX since a long time. It’s achieved by several techniques (ballooning, contend-based page sharing, demand paging) and the company uses it as a great selling point.

At the moment only one of the approaches used by VMware is also implemented by several competitors: the memory ballooning.
This feature comes as part of Xen (only for Linux guest OS at the moment) so any commercial hypervisor powered by Xen can offer it, including Citrix XenServer, Virtual Iron, Oracle VM and the operating systems from Novell and Red Hat.

Oracle is a contributor of the open source hypervisor and just before the release of Xen 3.3 decided to clarify that there’s no need to implement all the techniques that VMware: some improvements to the current Xen ballooning can grant a just fine memory overcommitment.

At the XenSummit 2008 Dan Magenheimer, Consulting Developer at Oracle (and once Principal Scientist of Virtualization Research at HP), presented a lecture and a whitepaper clarifying the point:

…While content-based page-sharing, VMM-based demand paging, and hotplug memory are all glamorous mechanisms that can be used to improve memory efficiency, the simple existing balloon driver provided by Xen, when combined with gray-box data collected by a few scripts, is sufficient to implement reasonable memory overcommit. More measurement and testing is ongoing in Oracle’s OnDemand group, but we believe that this very simple solution delivers the vast majority of the value of memory overcommit with a much smaller cost…

Labels: Xen

As expected, Xen.org announced the availability of Xen 3.3.

This new version of the open source hypervisor includes important features, including:

• Power management (P & C states) in the hypervisor
• Shadow3: optimizations to make this the best shadow pagetable algorithm yet, making Hardware Virtual Machines performance better than ever
• CPUID feature levelling: allows safe domain migration across systems with different CPU models
• PVSCSI drivers for SCSI access direct into PV guests
• Full x86 real-mode emulation for HVM guests on Intel VT: supports a much wider range of legacy guest OSes

As Xen powers a number of commercial hypervisors (Citrix XenServer, Virtual Iron, Oracle VM and by some degrees Sun xVM Server) as well as notable enterprise operating systems (Novell SUSE Enterprise Linux, Red Hat Enterprise Linux), it’s assured that all these products will start to integrate the new features over the next few months.

Download it here.

Labels: Xen

By now it’s well-known that Phoenix Technologies, the historical BIOS manufacturer, is entering the virtualization market with its own hypervisor.

Despite that, so far the company didn’t provide many details about the virtualization platform internals.

Now the LinuxWorld keynote given by Simon Crosby, CTO of Management and Virtualization department at Citrix, unveils that the engine behind HyperCore is Xen:

The slide also reveals that other major vendors are using Xen for their upcoming desktop hypervisors.

One is Lenovo, which announced a generic hypervisor for its notebook in March. Other remarkable ones are Intel, HP and Dell.
As virtualization.info didn’t attend the presentation we can’t say if these companies are building their own Xen-based hypervisors like Phoenix or if Crosby included them in the slide for other reasons.

This post will be updated with more details as soon as possible.

Labels: Xen

Xen.org just published the tentative Xen 3.3 datasheet which contains the full list of new features included in the new version of the open source hypervisor:

Performance and Scalability

• CPUID Levelling
• Shadow 3 Page Table Optimizations
• EPT/NPT 2MB Page Support
• Virtual Framebuffer Support for HVM Guests
• PVSCSI -- SCSI Support for PV Guests
• Full 16-bit Emulation on Intel VT

Security

• PVGRUB Secure Replacement for PYGRUB
• IO Emulation “stub domains” for HVM IO

Green Computing

• Enhanced C & P State Power Management
• Graphics Support
• VT-d Device Pass-Through Support

Miscellaneous

• Upgrade QEMU Version
• Multi-Queue Support for Modern NICs
• Removal of Domain Lock for PV Guests
• Message Signalled Interrupts

The datasheet is also interesting because it provides an updated list of the major Xen contributors: Intel, AMD, HP, Dell, IBM, Novell, Red Hat, Sun, Fujitsu, Samsung, and Oracle.

While most of the companies listed above are well-known names, finding a telco giant like Samsung is pretty uncommon.
In November 2007 Samsung was working to bring Xen on PDAs. In June 2008 virtualization.info reported that the company was porting Xen on the ARM architecture.

Virtualization may reach mobile devices soon.

Labels: Xen

Just two days ago Brian Madden published a very provocative analysis of the Citrix positioning in the virtualization industry, claiming that the current market share for XenServer is near zero and predicting that the company will eventually drop the open source engine in use, Xen, in favor of the just released Microsoft Hyper-V. And this would imply a shift of the community from Xen to KVM.

(virtualization.info covered the Madden analysis and many others in a very long article titled Microsoft Hyper-V: the day after)

Obviously, this prediction created a wide reaction and so far virtualization.info collected some feedbacks from readers believing that the scenario is perfectly possible.

Simon Crosby, CTO of Virtualization & Management Division at Citrix, spent a long post to answer to Brian Madden on all the points.

On the Citrix market share:

We have somewhere approaching 4,000 enterprise customers, and about 3000 trained channel partners. VMware claims 100,000 customers.  Citrix has about 220,000 customers and about a hundred million users.  The XenServer market share is small, and growing as rapidly as any such product can given the current VMware brand status, and the fact that we started well behind them.  We had a few key blockers for enterprise adoption, four fifths of which are addressed in our forthcoming XenServer 4.2 release.

On the drop of Xen:

It is important to state yet again that we are not in a competition for server sockets with Microsoft.   If that were the case, why would we have helped Microsoft to make Hyper-V a better hypervisor, by developing the shims and drivers that will allow Linux to run with optimal performance on Hyper-V?   The founding thesis of XenSource, and the continued strategy at Citrix, is to promote fast, free, compatible and ubiquitous hypervisor based virtualization.  If the hypervisor is free, why worry about who delivers it?

On the community shift to KVM:

It's just a VT/AMDV driver added to Linux to allow it to host additional VMs.  Great if your usage model is "first install Linux, then use your Linux skills to install VMs".  Unfortunately it doesn't address any of the other key requirements for virtual infrastructure (virtualization-aware shared storage, snapshotting, cloning, thin provisioning, HA, and much more) it is just another way to do basic CPU and memory virtualization ... at a time when Xen already offers Linux a typical overhead of under 1% (SPECJBB), and a rich set of value-added features.

Labels: Citrix, Microsoft, Xen

Just two weeks ago virtualization.info published an article detailing some of the conditions needed to bring virtualization to the embedded/mobile devices.

Being possible (and profitable) or not, one of the first platform that seems ready to go was KVM.
Now also Xen embraces the portable architectures.

At the end of the annual XenSummit, Samsung officially announced a port of the open source hypervisor to the ARM hardware.

The involvement of Samsung is a major sign of interest from the mobile industry, and the choice to start the porting from ARM a remarkable thing considering the huge diffusion of this processor.

The phone giant is working on Xen for Arm since over a year and the progress made so far can be tracked on this dedicated wiki.

There's also a very interesting presentation titled Secure Xen on ARM: Status and Driver Domain Separation that is worth a read.

Ready to see a virtual machine on the iPhone?

Labels: Xen

Keeping his last week promise, Stephen Spector, Senior Program Manager of Xen.org, published a release candidate of the updated Xen trademark policy.

It can be read here while waiting for the revision that the Citrix legal department will operate to avoid an invasion of Xen-something products.

The feedback and comments are welcome here. virtualization.info will forward them to Citrix.

Labels: Citrix, Xen

More than one year ago the Xen trademark became the major topic of discussion when talking about the relationship between XenSource, owning the rights at that time, and other companies adopting the open source hypervisor (Virtual Iron and Red Hat in particular).

Now Citrix, which obtained the Xen trademark after the XenSource acquisition, is about to update the use right policy as reported by Stephen Spector, Senior Program Manager of Xen.org, on the corporate blog.

While re-shaping the trademark policy around the community feedbacks, Citrix legal department is concerned about the uncontrolled use of Xen-something terms and may prohibit too open terms:

...Citrix believes, and hopes that the community understands, that use of other Xen-combined names might confuse potential users  of Citrix-sourced products as to the source of a particular product or service. Since all Xen-based commercial products on the market today (of which Citrix is aware) from other vendors are all non-Xen branded, Citrix believes that this is the appropriate time to clarify this issue.

For example, an ISV may create a service for registering servers running Xen and decide to call the service “XenRegister”.  A reasonable IT consumer could be confused and assume that the XenRegister service is sourced by XenSource and Citrix.  Instead, the ISV could call their service, for example, “VM Registration for the Xen® hypervisor” or “MegaRegister™ for Xen®,” or any other name which is in keeping with the Xen Trademark Policy and does not reasonably confuse an IT consumer as to its source...

Spector said there is a last version of the policy coming out for community inspection. We'll see how this issue really limited the use of the Xen trademark at that time.

Labels: Citrix, Xen

Recently ZDNet published a skirmish of words between Ian Pratt, Xen founder and chief architect, and Benny Schnaider, CEO of Qumranet (supporting the development of KVM), about the destiny of Xen and the right to be called hypervisor of KVM.

While the debate itself is not too much interesting, one of the reactions that it provoked is much more.

Anthony Liguori, Software Engineer at Linux Technology Center, contributor for both Xen and KVM ( and of Debunking Blue Pill Myth fame), used his personal blog to provide some interesting perspectives of why KVM was preferred over Xen for the integration in the Linux kernel:

...

Xen is a hypervisor that is based on the Nemesis microkernel. Linux distributions ship Xen today and by default install a Linux guest (known as domain-0) and do their best to hide the fact that Xen is not a part of Linux. They've done a good job, most users won't even notice that they are running an entirely different Operating System. The whole situation is somewhat absurd though. It's like if the distributions shipped a NetBSD kernel automatically and switched to using it when you wanted to run a LAMP stack. We don't ship a plethora of purpose-built kernels in a distribution. We ship one kernel and make sure that it works well for all users. That's what makes a Linux distribution Linux. When you take away the Linux kernel, it's not Linux any more.

...

When people talk about Xen not being merged into Linux, I don't think they realize that Xen will *never* be merged into Linux. Xen will always be a separate, purpose-built kernel. There are patches to Linux that enable it to run well as a guest under Xen. These patches are likely to be merged in the future, but Xen will never been a part of the Linux kernel...

Labels: Xen

The Xen open source hypervisor, powering Citrix XenServer, Virtual Iron and the upcoming Sun xVM Server, reached version 3.2.1.

The new minor release is just for bug fixing. Download it here.

Labels: Xen

A new open source project with ambitious aims is growing online: OpenNEbula (formerly GridHypervisor).

The tool consists in a management layer that interconnects multiple Xen hypervisors to offer a general purpose grid.

The cloud created by OpenNEbula has some interesting capabilities like:

• dynamic resizing (adding a new physical host immediately extends the cloud size)
• workload balancing (the product selects the best location for each virtual machine)
• cloud partitioning (the cloud can be segmented and provide isolation for different services)
• fault tolerance (each component of the cloud is independent and its failure doesn't impact others)
• on-demand provisioning (the number of virtual machine used for hosting a certain service are automatically selected)
• open and pluggable architecture (the product can be integrated with 3rd party tools to have more features, like virtual lab automation solutions, and can even support different hypervisors)

Such infrastructure seems similar to the one currently offered by Amazon with its Elastic Compute Cloud (EC2) platform, except for the on-demand provisioning capabilities (that the new project Scalr could provide soon).

OpenNEbula features a rich roadmap which includes support for VMware ESX and KVM.

The product is currently available only as Technology Preview and can be downloaded here.

Labels: Xen

XenSource committment in the Xen project has been questioned since the day a partnership with Microsoft was signed. The acquistion from Citrix in August 2006 raised even more concerns about the Xen destiny and the Citrix effort in the open source community that developed its new hypervisor.

Now ZDNet argues that Citrix move to rename Presentation Server in XenApp Server is a clear confirmation that those concerns were well founded.

Update: Citrix (through Simon Crosby, CTO of the Virtualization and Management Division and former XenSource CTO) fires back immediately:

• The Xen project is in great shape, superbly funded by Citrix and the community, and is operated independently from Citrix, by the Xen project Advisory Board. Citrix has more than doubled XenSource's open source team size already, and is continuing to develop new initiatives for Xen. At the most recent Xen developer summit in December, we had over 200 attendees, and there was fantastic participation from across the industry. Our own open source team operates independently from the product groups and has a blank check for headcount and resource.
• Citrix XenServer is a core foundational product to Citrix. Specifically, XenApp (formerly Presentation Server) and XenDesktop (formerly Desktop Server, addressing the VDI use case) will both include XenServer in all future releases. Why? Because XenServer is being optimized to run the XenApp and XenDesktop workloads, and provides a fantastic set of manageability, availability, scalability, and flexibility options to the XenApp/XenDesktop administrator, with incredible performance (very significantly better than VMware's). Citrix customers don't like using VMware for virtualizing Presentation Server, because of the very serious performance penalty, but they need to virtualize it for various reasons: test & dev flexibility, consistency of image management, DR, ease of provisioning etc. XenServer offers them all they need, at much better price/performance than VMware. XenServer 4.1 specifically contains optimizations for Presentation Server as a workload.
• XenServer itself continues to go from strength to strength. The new release 4.1 boasts over 50 new features and performance optimizations, and a profound and strategic tight coupling between the virtual infrastructure platform and smart virtualization aware storage, such as the NetApp devices. Expect a range of exciting announcements as we move down this path.

Labels: Citrix, Xen

From the Xen-devel mailing list Keir Fraser, Project Leader at XenSource, announces release of new Xen 3.2 version.

This new build introduces some important features:

• Preliminary PCI pass-through support (using appropriate Intel or AMD I/O-virtualisation hardware)
• Preliminary support for a wider range of bootloaders in fully virtualised (HVM) guests, using full emulation of x86 'real mode'
• ACPI S3 suspend-to-RAM support for the host system
• Xen Security Modules (XSM)
• Configurable timer modes for HVM guests, depending on how the guest OS manages time-keeping

As usual source code is available here while binaries will be soon released here.

Labels: Xen

The NetBSD Project released NetBSD 4.0 introducing full support for Xen 3.0 in domU and dom0. Previous version (3.1) of the operating system only supported the open source hypervisor in domU.

Not every architecture is included anyway: AMD64 support is planned no earlier than NetBSD 5.0.

Download it here.

Labels: Xen

On its corporate blog Barry Flanagan, Xen Technology Evangelist at Citrix, provides some interesting informations emerged during the last Xen Summit. One of them is the roadmap defined for the open source hypervisor, Xen, which is the key component of virtualization plaforms from Virtual Iron, Novell, Red Hat, Sun and obviously Citrix:

Server

• Performance and scalability optimizations
• Enable Smart IO devices
• SCSI pass-through

Security

• Domain0 disaggregation; XSM Xen Security Modules
• Secure boot, TPM, certification, multi-level secure systems

Client

• Power management
• Suspend and hibernate; Clock management
• 3D video direct h/w access; high-performance guest virtualization
• USB device pass-through

Another key information lays in the project statement, re-iterated now that XenSource has been acquired by Citrix:

• Build the industry standard open source hypervisor core engine that is incorporated into multiple vendors' products
• Be first to exploit new hardware acceleration features
• Help OS vendors paravirtualize their OSes
• Security must now be paramount
• Support multiple CPU types; big and small systems from server to client to mobile
• Foster innovation to be a great platform for research and experimentation
• Drive interoperability between Xen-based products and other virtualization products

During the entire 2007 several indication from multiple vendors (including VMware) partially revealed the intention to port hypervisors on mobile architectures, so 2008 may be the year for first attempts in this direction.

Labels: Xen

For the first time OpenVZ released these days a new class of patches for Linux kernel.

The new patches available for Red Hat Enterprise Linux 5 (both x86 and x64 versions), has been developed in a way it's compatible with Xen patches, which RHEL already offers out of the box. In this way users can decide which virtualization approach they prefer, or even run both of them in parallel.

In any other case OpenVZ and Xen patches would have been incompatible with each other obliging users to choose one.

The new patches are available here.

Labels: Xen

The US startup Thinsy Corporation joins today the growing crowd of virtualization vendors which are offering commercial products based on Xen hypervisor. Thinsy is the 7th commercial implementaion, immediately after the just announced Oracle VM.

Their EnSpeed VMM has yet to reach version 1.0, but already introduces a different approach in how virtual machines availability is granted: instead of relying on a NAS/SAN facility, this implementation uses a peer-to-peer disk synchronization technology called LiveSync, which allows virtual machines failover onto a secondary host if primary one fails.

Along with it Thinsy aslo provides a web based management solution called EnSpeed VM Orchestrator which provides basic operational capabilities.

Both products can be download here (it's unknown which kind of restrictions are in place or which will be the final price).

Labels: Xen

By surprise Oracle today announces its own hypervisor based on Xen: Oracle VM.

The new product includes a web management console and will be released for free (with optional support agreements) on November 14.

The move comes completely unexpected for a couple of reasons:

• So far the company was totally reluctant to embrace virtualization, refusing to change its licensing model and support policy
• Until today Oracle had a pretty good relationship with VMware: despite its official position on the technology it never discouraged the VMware salesforce to push Oracle RAC in virtual machines

On one side the announcement and all related documentation reveals how Oracle is just partially changing its position about virtualization. The Oracle VM FAQs report:

How are Oracle products priced and licensed for use with Oracle VM?
There is no change in pricing and licensing of Oracle's products for use with Oracle VM. Oracle counts and licenses physical processors on which the licensed programs are installed and/or running.

What is really changing is the support policy. Oracle now officially covers following products installed in its virtual machines:

• Oracle Database 10g Release 2 and Oracle Database 11g Release 1
• Oracle Application Server 10gR2 and 10gR3
• Oracle Enterprise Manager 10.2.0.4
• Oracle Berkeley DB 4.6
• Oracle TimesTen 7.0.3.1
• Oracle E-Business Suite 11.5.10 and 12
• Oracle PeopleSoft Enterprise 8.4.x and 9.0
• PeopleTools 8.49.07 and above
• Oracle Siebel CRM 8.0
• Oracle Hyperion 9.3.1

On top of that Oracle also states that is working on para-virtualization drivers for Microsoft Windows guest OSes, which performances the company doesn't consider acceptable at today.

On the other side with this release Oracle drastically changes its position towards VMware.

First of all the official support statement quoted above implies that any other hypervisor (including VMware ESX Server) will not receive similar support:

Will Oracle support customers who are using Oracle products on other x86 server virtualization environments?
Oracle VM is the only x86-based server virtualization environment on which Oracle products are supported.

Secondarily another part of the Oracle VM FAQs states that Oracle applications on Oracle VM (so we are talking about Xen hypervisor) are far better than on ESX Server:

How is Oracle VM three times more efficient than existing x86 server virtualization products?
Oracle ran many performance benchmarks comparing Oracle products running with Oracle VM against the existing leading server virtualization product and also with Oracle products on non-virtualized operating systems on x86 and x86-64. Oracle consistently saw much better resource utilization with an average of three times less overhead using Oracle VM, and also saw significant scalability with virtual SMP. In many cases, the comparison with real hardware was approximately equal in performance.

Now the announcement will have two side effects:

• All VMware customers which decided to trust company salesforce and migrated Oracle into ESX Server virtual machines will have a serious problem and will need to move away as soon as possible
• Oracle example may push other major ISVs to adopt same policy, supporting virtual versions of their applications only on their own hypervisors, which would lead to an uncontrolled proliferation of virtualization platforms. And this will boost demand for management solutions which support multiple virtualization vendors.

Update: VMware promptly reacts to the Oracle announcement and contacted virtualization.info to provide its answer:

We are pleased to see major application providers like Oracle beginning to understand and recognize the benefits of virtualization. We believe Oracle's announcement is in response to the overwhelming number of customers that have standardized on VMware to run enterprise applications including Oracle. We hope this will be the first of many steps that Oracle takes towards broad enablement of virtualization. Our many mutual customers are looking for stronger virtualization support from Oracle, including clear and consistent licensing guidelines for running Oracle software in virtualized environments.

Labels: Xen

EarthWeb interviewed former XenSource CTO, Simon Crosby, about future of new Citrix XenServer and competition with VMware. In one answer Crosby revealed a major news:

...

Q: The XenSource applications are based on open source. In terms of the virtualization market, what are the pluses or minuses of an open source approach?

Open source is an extremely valuable tool for innovation. One of the key things about the Xen code base is that it can be delivered to market by multiple vendors, and will be.

One of the biggest challenges that the hardware vendors have had is that vendors like Microsoft take five years to get new features to market for them. But of course we have support on Day One. So the day that the first Intel VT CPU ships, we have the support. The day the hardware virtualization [launches] we have the support. So we've become the industry's first and best support for an enhanced hardware experience.

And at the same time, we've been very anxious to make sure that Xen as an engine was open sourced, but that multiple different vendors could have economic business models built around that. So we commoditize the "engine" - it's the code base that everyone agrees should be commoditized - and then it has much broader applicability.

So, for example, Xen runs on [certain] PDAs, and Samsung is doing work with those as a product prototype. But it also runs on supercomputers from SGI. That way, we don't have just one "car" - thereìs everything from Porches to Minis. So you don't limit its applicability...

Read the whole interview at the source.

Labels: Xen

Today Citrix announces that XenSource acquisition is completed, and confirms that Xen development will still be led by Ian Pratt, co-founder of XenSource.

Citrix also reveals that Ian Pratt is now an employee, which implies a remarkable impact on how the open source hypervisor will evolve.

So the question is not just about how much committment Citrix will have in open source, but how much support thet will continue to receive by other Xen contributors, like IBM and Red Hat, which probably don't feel too comfortable about company's deep relationship with Microsoft.

Labels: Citrix, Xen

From the Xen-devel mailing list Keir Fraser, Project Leader at XenSource, announces release of new Xen 3.1.1 version.

The very short announcement reveals this is a bugfix release only. All vendors using the open source hypervisor (CItrix/XenSource, Virtual Iron, Novell, Red Hat and now Sun) are expected to update their products accordingly in the coming months.

Binaries for Xen 3.1.1 should be available shortly here.

Labels: Xen

Linus Torvalds just announced availability of new Linux kernel 2.6.23.

It brings several improvements in the hardware virtualization space with the introduction of Xen and lguest support.

Kernel Newbies provides a good summary:

Lguest host support (CONFIG_LGUEST)can be compiled as a module (lg.ko). This is the host support - one you load it, your kernel will be able to run virtualized lguest guests. But kernel guests need to compile lguest guest support in order to be able to run under the lguest host. The configuration variable that enables the guest support is CONFIG_LGUEST_GUEST - but that option will be enabled automatically once you set CONFIG_LGUEST to 'y' or 'm'. This means that a kernel compiled with lguest host support does also get lguest guest support. In other words, you can use the same kernel you use to be a host as guest kernel. In order to load and run new guests, you need a loader userspace program.

Part of Xen has been merged. The support included in 2.6.23 will allow the kernel to boot in a paravirtualized environment under the Xen hypervisor. But support for the hypervisor is not included - this is only guest support, no dom0, no suspend/resume, no ballooning. It's based in the paravirt_ops infrastructure.

Anyway the most important news is support for virtual SMP inside KVM guest operating systems:

• Enable guest smp
• Implement rdmsr and wrmsr. This allows smp Windows to boot
• i386: Allow KVM on i386 nonpae

More improvements are expected also in the OS virtualization space: at LinuxWorld 2007 Andrew Morton said kernel development will focus much on these technologies during the next 2 years.

Labels: KVM, Xen

VMware products are not the only ones suffering security vulnerabilities. The wider audience the bigger chances to find out developers errors in every software, in every industry.

So after bugs which obliged VMware to release new Workstation 6.0.1, Player 2.0.1, ACE 2.0.1 and Server 1.0.4, it's now Xen turn.

Quoting from Secunia:

Joris van Rantwijk has reported a vulnerability in Xen, which can be exploited by malicious, local users to gain escalated privileges.

The vulnerability is caused due to an input validation error in tools/pygrub/src/GrubConf.py. This can be exploited by "root" users of a guest domain to execute arbitrary commands in domain 0 via specially crafted entries in grub.conf when the guest system is booted.

The vulnerability is reported in Xen 3.0.3. Other versions may also be affected.

Grant only trusted users "root" privileges to guest domains.

Read the whole securiy bulletin at the source.

Since Xen is used as virtualization engine by XenSource, Virtual Iron, Novell and Red Hat, all of their commercial solutions may be affected by the same vulnerability. Check with vendors to confirm this.

Labels: Xen

In a short post introducing upcoming Solaris 8 Branded Zone for Solaris Containers, Marc Hamilton, Vice President of Solaris Marketing, reveals how upcoming Sun hypervisor, based on Xen engine, will be called: xVM.

...

Of course Solaris Containers is just one of the many virtualization technologies from Sun that can help you reduce cost and complexity in your data center. Our CoolThreads servers support a hypervisor based virtualization technology called LDoms (Logical Domains) and we will soon introduce the Solaris x86 Virtual Machine (xVM) hypervisor for Solaris running on systems with x86 processors from Intel and AMD...

Read the whole post at the source.

Labels: Xen

InformationWeek published a brief but interesting interview with Citrix Corporate Vice President of WorldWide Marketing, Wes Wassom, and XenSource CEO, Peter Levine, obviously about recent acquisition.

A couple of answers are exposing crucial details to figure out Xen future developments:

How many of the hypervisor developers are employed by XenSource?
There are five to six guys who do a lot of work on the Xen project that are part of XenSource.

...

How will you maintain that community?
We started in parallel with the acquisition discussions to elevate the Xen project and community by appointing a panel to provide oversight during the transition. It will maintain a distinction between the open source code and commercial efforts. ... We are working on that collaboratively with IBM, Intel, HP, Novell, and Red Hat. We are just coming up with a model for that in the next 45 to 60 days...

virtualization.info also published an interview with Citrix's Wes Wassom, and XenSource CTO, Simon Crosby, exposing more details about upcoming strategy about partnerships and competition.

Labels: Citrix, Xen

In March 2007 Ulrich Drepper, the GNU libc maintainer, was defending KVM project against immaturity claims.

One day before VMware IPO he's back again on the topic, this time severely criticizing Xen / ESX Server hypervisor architectures (which implies criticizing upcoming Microsoft codename Viridian architecture as well):

People are starting to realize how broken the Xen model is with its privileged Dom0 domain. But the actions they want to take are simply ridiculous: they want to add the drivers back into the hypervisor. There are many technical reasons why this is a terrible idea. You'd have to add (back, mind you, Xen before version 2 did this) all the PCI handling and lots of other lowlevel code which is now maintained as part of the Linux kernel. This would of course play nicely into Xensource's (the company) pocket. Their technical people so far turn this down but I have no faith in this group: sooner or later they want to be independent of OS vendors and have their own mini-OS in the hypervisor. Adios remaining few advantages of the hypervisor model. But this is of course also the direction of VMWare who loudly proclaim that in the future we won't have OS as they exist today. Instead only domains with mini-OS which are ideally only hooks into the hypervisor OS where single applications run...

Drepper is employed by Red Hat, which is integrating Xen in its distribution for a long time, but recently stopped mentioning the term Xen at all. Now that XenSource, employing many Xen developers, has been acquired by Citrix, Red Hat may find difficult to still stick with Xen.

Is Drepper offering persuasive argumentations to make his employer switch to KVM?

Ulrich Drepper is not the only open source code guru against virtualization players: yesteday it emerged that also Christopher Helwig, Linux SCSI storage maintainer, is openly against VMware ESX Server, considering the hypervisor a violation of GPL license.

Thanks to OSNews for the news.

Labels: Xen

The Register yesterday's scoop has been confirmed today with expected official announcement by Citrix, which contains key informations about open source project Xen, Microsoft-XenSource relationship, XenSource other partnerships:

Citrix Systems, Inc., the global leader in application delivery infrastructure, today announced a definitive agreement to acquire XenSource, Inc. of Palo Alto, Calif., a privately held leader in enterprise-grade virtual infrastructure solutions, for approximately $500 million in a combination of cash and stock, which includes the assumption of approximately $107 million in unvested stock options. This acquisition moves Citrix into adjacent server and desktop virtualization markets, expected by Citrix to grow to nearly $5 billion over the next four years.

...

The acquisition is expected to close in the fourth quarter of 2007 subject to the satisfaction of closing conditions.

...

Today's acquisition announcement comes on the heels of a substantial new release of XenEnterprise, the company's flagship commercial product line powered by the Xen engine.

...

Version 4 will further accelerate an installed base that has more than doubled in the last 90 days to over 650 customers.

...

Upon close of the acquisition, the XenSource team and products will form the core of the new Virtualization & Management Division of Citrix dedicated to building and growing these important new businesses. Peter Levine, XenSource, CEO, will lead the new division, reporting directly to Mark Templeton, Citrix president and CEO. Under Peter's leadership, Citrix is also committed to maintaining and growing its support for the Xen open source community, led by XenSource co-founder and Xen project leader, Ian Pratt. Between now and the close of the acquisition, XenSource will work with the key contributors to the Xen project to develop procedures for independent oversight of the project, ensuring that it continues to operate with full transparency, fairness and vendor neutrality - principles that are critical to the continued role of Xen as a freely available open source industry standard for virtualization.

...

The acquisition will also strengthen each company's strong partnership with Microsoft and commitment to the Windows platform. As an independent company, XenSource has built a strategic relationship with Microsoft designed to ensure broad interoperability between XenSource products and the upcoming Microsoft Windows hypervisor, code named "Viridian". This relationship complements and broadens the successful partnership between Citrix and Microsoft in the Windows application delivery, application networking and branch office infrastructure markets.

...

Assuming the transaction closes as expected, the acquisition is expected to add approximately $1 million in revenue and $3 million in cost of revenues and operating expenses to fiscal year 2007. The acquisition is expected to add approximately $50 million in revenue and $60 to $70 million in total cost of revenues and operating expenses to fiscal year 2008. The transaction will also result in approximately an $8 to $10 million non-cash expense charge for the write-off of in-process research and development in the quarter in which the acquisition closes...

Before acquisition XenSource received $41.5 million from venture capital backers Accel Partners, Ignition Partners, Kleiner Perkins Caufield & Byers, New Enterprise Associates and Sevin Rosen Funds.

Citrix stock (CTXS) didn't perform well despite the acquisition news, starting today at $32.49, gaining 3% when announcement was made, but closing with a -1.5% (altought after hours trading are bring a +3.04% at time of writing).

virtualization.info published a preliminary analysis of how this acquisition may impact the virtualization market here.

The virtualization.info Virtualization Industry Radar has been updated accordingly.

Labels: Citrix, Xen

Brian Madden is reporting a rumor claiming Citrix is in talk for Citrix acquisition and deal amount may be as high as $500 million.

Almost at the same time Credit Suisse, which is a lead underwriter of upcoming VMware IPO, released a research analysis about why Citrix should buy an hypervisor and why XenSource is the best candidate at the moment:

We believe that Citrix may be interested in acquiring core virtualization infrastructure and management tools as part of a strategy to broaden its product portfolio to better address the next generation data center-based on our analysis of the desktop virtualization market as well as recent feedback from industry participants, combined with management's recent public comments that virtualization and systems management are areas of potential interest for acquisition.

In our opinion, one of the Xen developers-either XenSource or Virtual Iron-could represent an attractive target for Citrix, as we believe that hypervisor and associated management solutions would be complementary to Citrix's long-term vision of offering scalable application and desktop delivery. While these companies' virtual infrastructure management tools are more immature versus more-established vendors, if Citrix can develop robust management software through increased R&D while leveraging the open source Xen hypervisor, Citrix could establish itself as a strong competitor in both desktop and server virtualization within two to three years. Acquiring XenSource could also strengthen Citrix's relationship with Microsoft. Conversely, while timing and pricing for any potential transaction is unknown, the near-term implication of an acquisition of either vendor would likely be some EPS dilution...

Read the whole analysis at source.

(virtualization.info is mentioned among trusted sources for this research)

Thanks to DABCC for the news.

Labels: Citrix, Xen

Quoting from the HP official announcement:

...

HP's addition of Xen and guest operating system support for Debian to the HP Partner Virtualization Program enables independent software vendors to build and verify applications in a secure, virtualized environment. Through the program, partners have access to HP's entire server portfolio using HP Integrity, ProLiant and BladeSystem platforms running a broad range of operating systems and virtual machines...

Labels: Xen

From his corporate blog Simon Crosby, Co-Founder and CTO at XenSource, announces a major goal achieved in the Xen project:

Today is an important day in the history of the Xen project. Linus has just merged the XenSource patches into upstream for release as part of the 2.6.23 kernel.

About a year ago, XenSource, the Linux kernel community and VMware set out to develop a common interface into the Linux kernel that would allow for optimal execution on a hypervisor, taking advantage of paravirtualization - the key innovation of the Xen project that will also be adopted into Solaris 10, and that can be expected in the forthcoming Windows Server, Longhorn.

...

VMware's implementation of the paravirt_ops API is already in upstream, and VMware has now offered beta level support for this in their VMware Player and desktop products, though they have yet to announce commercial support.

...

This work will allow future Linux distro kernels to simply base of kernel.org, and automatically inherit Xen support, without needing to pull the Xen paravirtualization patches into their kernel as a separate effort.

Read the whole post at source.

Labels: Xen

Jeff Gould at Interop News wrote a very long and interesting article on Xen market status

...

Suffice it to say there has been a lot of excitement and optimism in the pundit community about Xen.

...

But now that Novell and Red Hat have both been shipping Xen in their commercial Linux distributions for some months, things have grown eerily quiet. Sure, there is still product news coming out of the Xen vendors, and we'll get to that in a moment. But what I'd really like to know is - who's actually using this stuff in production? And I mean actual end-user organizations, not ISPs or hosters. Based on the absence of Xen-related chatter, my guess is that production users of Xen are still few and far between.

...

Taking Novell, Red Hat, XenSource and Virtual Iron together, you'd be hard pressed to come up with a dozen named reference customers for Xen.

...

If we take off our open source blinders for a moment and look at Xen objectively, we can begin to spot a few of the flaws that appear to be holding it back.

The first problem with Xen is that as a piece of software it is far less mature than VMware ESX.

...

Then there is the question of performance.

...

A year ago I thought that Xen offered Red Hat a huge opportunity to take some market share from Microsoft before the release of Longhorn (Windows Server 2008). Apparently Red Hat thought so too, because they planned and promoted the release of the all-important RHEL5 around Xen, even delaying the launch date by several months to smooth out the snags encountered in the integration effort.

But today it's apparent that however Xen evolves in the future, it isn't going to be the Longhorn killer Red Hat thought it would be...

Read the whole article at source.

Labels: Xen

Fedora Linux distribution is slowly integrating virtualization as basic OS capability.

In Fedora Core 5 Red Hat initially integrated Xen hypervisor, followed by a basic GUI for it in Fedora Core 6: virt-manager. Now new version 7 includes Linux kernel 2.6.21 and then offers out-of-the-box its second virtualization platform: KVM.

Integration of kernel 2.6.21 also implies Fedora 7 sports paravirt-ops framework and VMware VMI interface. This means new VMware Workstation 6.0 should be able to run it as a para-virtualized guest (with a major performance boost).

Last but not least Fedora 7 updated embedded Xen package to new version 3.1 (formerly 3.0.5).

Read full release notes about virtualization packages here or download the distribution here.

Labels: KVM, Xen

After a long development phase Xen reaches state 3.1 (previously labelled as 3.0.5) and gains some interesting features:

• XenAPI (providing support for virtual lab management capabilities and configuration metadata)
• Dynamic memory control for non-paravirtualized virtual machines (Windows)
• Support for basic save/restore/migrate operations for non-paravirtualized virtual machines (Windows)
• Support for 32bit paravirtualized guests
• Support for virtual disks on raw partitions

Download it as source, binary tarballs or RPMs.

From now on expect a new release of XenEnterprise and Virtual Iron platforms based on the new engine release.

Labels: Xen

Quoting from SearchEnterpriseLinux:

...

RHEL 5.1 will bring hardware virtualization feature improvements, paravirtualized drivers, the Xen 3.0.5 hypervisor and features like non-uniform memory access (NUMA) topology and loopback removal. Also, 5.1 will support live moves of virtual machines in clusters, along the lines of the functionality of VMware's VMotion...

Read the whole article at source.

RHEL 5.1 is expected this fall, followed by 5.2 version planned for early 2008.

Xen 3.0.5, mentioned in the above article, has been renamed Xen 3.1 last week.

Labels: Xen

From official Xen development mailing list Keir Fraser, Project Leader at XenSource, announces a major change in Xen version numbering along with several new features:

The imminent next Xen release introduces a host of important new features including PV 32-on-64, HVM save/restore, and XenAPI 1.0. Now is a good time to bump our version number and reclaim the redundant second digit!

We plan to rename the xen-3.0.5-testing.hg tree to xen-3.1.0-testing later today. The release candidate will be renamed to 3.1.0-rc4. The final release will be called 3.1.0 (as opposed to 3.0.5-0 in the old numbering scheme).

Further bug-fix releases in the 3.1 series will be called 3.1.x (as opposed to 3.0.5-x in the old numbering scheme)...

Read the whole message at source.

Thanks to Tim Freeman for the news.

Labels: Xen

After last month comparison of Xen 3.0.2 and OpenVZ for Linux kernel 2.6.16 made by Björn Gross-Hohnacker for his diploma thesis, this time is HP Labs' turn to perform a benchmark analysis.

This new 14 pages document titled Performance Evaluation of Virtualization Technologies for Server Consolidation exposes a bigger overhead in Xen over OpenVZ:

...

In this paper, we evaluate two representative virtualization technologies, Xen and OpenVZ, in various configurations. We consolidate one or more multi-tiered systems onto one or two nodes and drive the system with an auction workload called RUBiS.

We compare both technologies with a base system in terms of application performance, resource consumption, scalability, low-level system metrics like cache misses and virtualization-specific metrics like Domain-0 consumption in Xen.

Our experiments indicate that the average response time can increase by over 400% in Xen and only a modest 100% in OpenVZ as the number of application instances grows from one to four. This large discrepancy is caused by the higher virtualization overhead in Xen, which is likely due to higher L2 cache misses and misses per instruction. A similar trend is observed in CPU consumptions of virtual containers. We present an overhead analysis with kernel-symbol-specific information generated by Oprofile...

Read the whole paper at source.

Labels: Xen

Quoting from CRN:

The Xen project will soon release an API for developing high-end management features like those in VMware's VMotion and Virtual Infrastructure 3 platform. At the annual Xen Summit held this week at IBM's Watson facility in Yorkstown, N.Y., the open-source project leaders said the Xen 3.05 update with the new API and enhanced 64-bit support would be available within a few weeks.

The 3.06 update with support for Intel's VT-d and possibly AMD's VT-d will be available in the next two to three months, said Ian Pratt, project lead.

...

The ability to do library relocations of Windows guests, another new feature in the 3.05 update, is significant because it will allow the dynamic relocation of Windows workload, essential for ISVs to offer VMotion-like features, Pratt said. The Xen software has supported library locations for Linux for several years, he added...

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Labels: Xen