Monthly Archives: November 2009

Have I got a story for you!

Does your head ache because you’ve been beating it against a stone wall when trying to build Xen binary executables from the distributed source code?  I know how you feel!  I’ve been fighting that good fight too for a while now.  I’ve learned some amazing facts as I progress – with full glacial speed.  I probably should admit right up front that I’m NOT the worlds greatest code wizard.  (Likely that’ll be evident as you read my story.)

Except I didn’t write it so I could bask in glory.  I put it up because it explains some of the things that sabotage novice Xen builders.  These things took me MUCH effort to learn, and I hope they will help you too.  (Also because I hope you like a good story.)

It’s an ongoing story which frankly is far from complete.  I will keep putting up more content as I move along.  Let’s make a deal:  I’ll keep "growing" this story and notifying you when there’s more to read – IF you submit comments providing feedback & corrections.  Let’s make this a community effort, with the eventual goal of creating a really helpful howto for the xen documentation.

So without any further ado: read it!

Libxenlight Released

From xen-devel:

I am pleased to announce “libxenlight”, a new small and lightweight C library that refactors existing code in a coherent and easy to use API to interface to the hypervisor and xenstore to perform operations such as domain creation and destruction, suspend/restore and pci passthrough.

The goals of libxenlight are:

– be easy to use and to extend
– provide a simple and robust API for tool stacks to do xen operations
– create a common codebase for the lower-level implementation of all the
various xen tool stacks

At the moment libxenlight implements domain creation, destruction and list domains; next items on the roadmap are suspend, resume and pci passthrough.
Libxenlight has been tested only on Linux but we would like to make it work on other systems as well. To aid development and testing we have created a small command line utility called “xl” that invokes the API.

We believe there is significant value in having all the various tool stacks (xend, xapi, xenvm, libvirt etc) use a common lower-layer, and so hope developers will embrace this project, contribute to it, and move their favoured stack over to using it.

Project Remus 0.9 Released

From xen-devel:

It’s my pleasure to announce the release of Remus 0.9!

Remus provides comprehensive fault tolerance for Xen virtual machines. If the physical machine hosting your VM fails, the backup can take over instantly, as if you had migrated it to the backup at the instant before the failure occured. There’s no need for recovery, because the backup is always completely up to date. Furthermore, Remus runs completely transparently, requiring no changes to your existing guests.

This release works with the tip of the xen-unstable repository, and supports PV and HVM in 32-on-32, 64-on-64, 32-on-64, and 64-on-32 configurations. It has been tested using Linux (Ubuntu) PV guests, and both Linux and Windows XP under HVM.

I believe that it is now ready for inclusion in Xen, and I would love to have people try it out and let me know how it goes.

You can find more information, including installation and usage instructions, at the web site:

The web site includes a list of improvements I have in mind over the short term. Ideas (and patches) welcome!