3.14. Configuring Virtual Machines in a Clustered Environment

When you configure your cluster with virtual machine resources, you should use the rgmanager tools to start and stop the virtual machines. Using virsh to start the machine can result in the virtual machine running in more than one place, which can cause data corruption in the virtual machine.
To reduce the chances of administrators accidentally "double-starting" virtual machines by using both cluster and non-cluster tools in a clustered environment, you can configure your system by storing the virtual machine configuration files in a non-default location. Storing the virtual machine configuration files somewhere other than their default location makes it more difficult to accidentally start a virtual machine using virsh, as the configuration file will be unknown out of the box to virsh.
The non-default location for virtual machine configuration files may be anywhere. The advantage of using an NFS share or a shared GFS2 file system is that the administrator does not need to keep the configuration files in sync across the cluster members. However, it is also permissible to use a local directory as long as the administrator keeps the contents synchronized somehow cluster-wide.
In the cluster configuration, virtual machines may reference this non-default location by using the path attribute of a virtual machine resource. Note that the path attribute is a directory or set of directories separated by the colon ':' character, not a path to a specific file.

Warning

The libvirt-guests service should be disabled on all the nodes that are running rgmanager. If a virtual machine autostarts or resumes, this can result in the virtual machine running in more than one place, which can cause data corruption in the virtual machine.
For more information on the attributes of a virtual machine resources, see Table B.26, “Virtual Machine (vm Resource)”.