PUBLIC MARKS from camel with tags lvm & xen

A virtual machine snapshot is a great feature, freezing the current state of a virtual machine. Unfortunately, open source Xen doesn't offer support for snapshots -- but Linux does. Since open source Xen always uses Linux as its privileged domain, you can use Linux commands to create snapshots.

If you're using LVM based storage for your domains this script will create a snapshot and backup each server to a local drive or a remote system using rdiff-backup.

For those running Xen on servers with no back-end SAN, the following instructions detail the steps necessary to move an LVM-based virtual machine to a new physical host. There may be more elegant ways to achieve this, but this is what worked for me.

Nous verrons dans cet article comment installer Xen sur une machine n'ayant pas les instructions matérielles de virtualisation (VT) en utilisant LVM pour partitionner avec flexibilité nos différentes machines virtuelles. Le tout est réalisé grâce à Debian Etch avec les bons noyaux qui vont bien. J'ai aussi utilisé le noyau officiel de chez Xen afin d'avoir quelque chose de propre (enfin dans la limite du possible). Attention, mon tutoriel prends de véritables adresses IP, je n'ai donc aucun besoin de NAT. Si tel est votre problème, achetez le numéro 100 de GLMF, il contient le serveur parfait et un setup bien plus avancé que le miens :)

We have implemented a 2-node HA Xen cluster, which consists of two physical machines (hosts,) and runs several virtual servers (guests) each, for our company's internal services (mail, web applications, development, etc.) When one host gets down unexpectedly, the other host physically kills it (STONITH - power down or reset) and then takes over all the guests the failed host was running. When we want to shutdown a host machine for maintenance (to replace a fan, add disk or memory, etc.), we just type the usual shutdown command, and the guests are automatically live-migrated to the other host. Since the guest servers keep running throughout the migration process, except for the less than a second pause, users would never even notice the event.