Monthly Archives: September 2011

Xen at OpenStack Design Summit and Conference

Xen OpenStack LogoEvery 6 months the OpenStack community gets together to discuss plans for the next release. Next week in Boston will be the Essex Design Summit and Conference. Myself and Ewan Mellor will be representing If you want to get together next week and discuss anything related to Xen, XCP, or OpenStack, then do get in touch with me (

At the summit, I’ll be leading a session on Project Kronos. There will also be a session on XenServer and KVM feature parity.

At the conference, be sure to catch the talk that Ewan and I are presenting on the initiatives related to OpenStack. Ewan is also on a couple panel sessions that you won’t want to miss.

This is a great chance to get your head back in the cloud. Hope to see you there!

XenSummit Asia : First Talks Announced

After nearly two weeks of travelling (Xen Hackathon two weeks ago, the Open World Forum last week), I have finally managed to publish location details, hotel information and the first 10 talks for XenSummit Asia, held Nov 2-3 in Seoul, Korea. I wanted to thank the Program Committe Members Mr. Sang-Bum Suh, Prof. Chuck Yoo, Mr. Sungi Kim and Ian Pratt for helping select the content for the summit.

The summit will be hosted in the Hana Square Auditorium on the Science Campus of Korea University. As usual, we will need to charge a small fee for covering costs. Because we are somewhat behind in publishing information regarding XenSummit, we decided to publish new information as it appears. By next week, I should have the complete speaker line-up, schedule, hotel discount information and will be able to open registration for the summit.

Given that Korea is the home of the Xen ARM project, led by Samsung, we will naturally hear much about Xen on ARM. You can also expect Xen research and developer talks and some Xen user stories. I am particularly excited about the “Xen @ Google” talk. With the Xen hypervisor powering 90% of the public cloud, there will also be a bit of cloud related content such as “Deep Dive into OpenStack” and “Skylark: Easy Cloud Computing“.

Stay tuned and see you at XenSummit!

XCP 1.1 RC1 Release

The XCP team would like to announce that, after a long time in beta, we’ve released XCP 1.1 RC1, which we hope will become our final release. Here is a list of issues that we’ve resolved since the beta release:

  • The license expiry bug has been resolved. This was the cause of the DMC issues reported in the beta, so those issues are resolved as well.
  • For OpenStack and others, support for ebtables and other netfilter options have been added to the kernel. These options have been disabled by default, but can be re-enabled with simple sysctl commands. These are the same kernel changes that will be included in the upcoming XenServer 6.0 release.
  • The Xapi version override feature has been added back in. This allows users to effectively rebrand their XCP boxes as XenServer hosts, in order to work better with products such as XenCenter.
  • It is possible to upgrade from XCP 1.0 to XCP 1.1 RC1, but it is not possible to upgrade from the beta to the RC.

Thanks to all the people who participated in the beta program, and who filed bug reports for us. It’s always really exciting for us hear from people who are using XCP, and we hope that this release is the best version of XCP yet. Jobs Pages, Changes

For those of you who have not noticed, has now a jobs page and we made changes to the Wiki main page.

Jobs Page
We created a community jobs page, where companies that are active in the community can post job offerings. Jobs listed on this page are required to have a relationship to the Xen open source community, but can include the development or use of proprietary system as long as they are related to Xen. We will keep the page up-to-date and make sure that jobs in the open source community are more prominently shown on the page. If you want a job listing added, get in touch with me.

Wiki Front Page
At the Hackathon, a few of the attendees sat together to make the Wiki Front Page more useful. The page now highlights links to popular and recently changed pages, a section pointing to useful documentation, a section linking to companies and individuals offering services around Xen and projects and products related to Xen and a Developer Resources section.

Xen Hackathon crazy idea: insmod xen

One of the fun things about a hackathon is the chance to get everyone together in a room and just talk about crazy ideas you might try at some point in the future.

One of the advantage that a certain competing virtualization technology has over Xen is that you don’t have to reboot to start using it. It’s not that big of a thing, but if you just want to play around with VMs, the additional step of rebooting and probably having to muck about with a grub entry makes it pretty certain that casual users will prefer our competition.

Wouldn’t it be great, someone said, if you could just do “insmod xen” in a running kernel, and have it hoist up the kernel (which is currently running on bare metal), put Xen underneath, and make the currently running kernel into domain 0?

The idea sounds pretty crazy at first, but after some examination, it’s actually quite do-able. In fact, there’s precedent: Windows 2008, apparently, does that when booting into Hyper-V. It may involve a certain amount of switching from bare metal code to PV code; but there’s precedent for that too, in the form of SMP alternatives.

One thing that it would depend upon is another project we’ve been kicking around for a year or so now, that being running dom0 in an HVM container. That would greatly reduce the amount of PVOPS necessary to run Linux as dom0, making the “hoist” a lot cleaner.

We have a lot of work to do before this can become a priority, but it’s a project that’s attractive enough that I’m sure someone will pick it up in due time, at which point there’s no technical reason that Xen can’t be as convenient for casual users to being using as any other virtualization technology out there.

Xen Hackathon Munich

It is day 3 of the Munich Hackathon and I wanted to thank Fujitsu and Jürgen Groß for hosting and organizing the event, as well as the social activities in the evening. Besides the coding, networking and getting to know each other which is always a key part of such Events, a few noteworthy initiatives were discussed and started.

Yesterday we had a long group discussion on what we need to do to make Xen and more attractive to our users. One of ther key outcomes of the session was that we must improve documentation! To me that has been clear for a while, but of course it is hard to do this without developers buying into the idea and driving the creation and maintenance of documentation. One of the key ideas discussed and agreed, was to embed documentation into the source tree and build a docset from source. To maintain the docs, patches would be required to modify documentation sources, if they have an impact on the UI. We will still need to investigate what technologies to use and how to do this in practice. Besides the how, we discussed the what and agreed that command line guides, HOWTO documentation and provide better config examples for xl are needed.

We also need a new Wiki, which is something I have been investigating. Some of our developers volunteered to help me identify which documentation on is out-of-date and what is important, so hopefully we will be able to make significant progress in this area soon.

Jürgen from Fujitsu also had a great idea for a new initiative based on some work that Fujitsu has done recently. How about creating a Xen Live-DVD which can boot on an existing windows installation and possibly on other operating systems. This should be possible with minimal mods to the installed system and it would be great if we could install the system on a free partition of the disk enabling Windows either on bare metal or as DomU under Xen (selectable via grub). Fujitsu has built something similar for internal purposes that installs a SLES based Xen system via USB or disk onto a free hard disk. Windows can be used bare metal or as DomU and is accessed via rdesktop; albeit there is no graphics pass-through support for now. To make this possible a few mods to Windows are needed, such as configuration of network (bridge), registry entries to enable boot from (emulated) IDE-disk and to enable rdesktop.

Anyway, if this sounds interesting to you, I want to hear from you and we can see whether we can get a Xen initiative off the ground.