The following will install and configure DRBD, OpenAIS, Pacemaker and Xen on OpenSUSE 11.1 to provide highly-available virtual machines. This setup does not utilize Xen's live migration capabilities. Instead, VMs will be started on the secondary node as soon as failure of the primary is detected. Xen virtual disk images are replicated between nodes using DRBD and all services on the cluster will be managed by OpenAIS and Pacemaker. The following setup utilizes DRBD 8.3.2 and Pacemaker 1.0.4. It is important to note that DRBD 8.3.2 has come a long way since previous versions in terms of compatibility with Pacemaker. In particular, a new DRBD OCF resource agent script and new DRBD-level resource fencing features. This configuration will not work with older releases of DRBD.

This document does not cover the configuration of Xen virtual machines. Instead, it is assumed you have a working virtual machine configured locally with a file-based disk image. As an example, our domU resource will manage a Debian virtual machine configured in debian.cfg.

Visit these links for more information on any of these components as well as additional documentation:

DRBD - http://www.drbd.org
Pacemaker - http://www.clusterlabs.org
OpenaAIS - http://www.openais.org

Contents:

1. Install Xen
2. Install and Configure DRBD
3. Install and Configure OpenAIS + Pacemaker
4. Configure DRBD Master/Slave Resource
5. Configure File System Resource
6. Configure domU Resource
7. Additional Information

1. Install Xen

The easiest way to install Xen and its prerequisites is through the yast command line tool:

# yast

Choose 'Virtualization' -> 'Install Hypervisor and tools'. If you're working on a remote server you may need to answer 'No' when asked about installing graphical components. Select 'Yes' when prompted about Xen Network Bridge.

Select 'System' -> 'Boot Loader' and set the Xen kernel as the default kernel.

Reboot.

At this point, the Xen kernel should be booted and a network interface br0 should be configured as a bridge to eth0.