Novell LINUX ENTERPRISE SERVER 11 - VIRTUALIZATION Manual page 47

machine can be migrated to other machines in order to avoid interruption of service.
These are only two examples, many more reasons may apply to your personal situation.
Before starting, some preliminary considerations regarding the VM Host Server should
be taken:
• All VM Host Server systems should use a similar CPU. The frequency is not so
important, but they should be using the same CPU family. To get more information
about the used CPU, see cat /proc/cpuinfo.
• All resources that are used by a specific guest system must be available on all in-
volved VM Host Server systems. This means, the network bridges must be in the
same subnet, and all used block devices must exist on both VM Host Server systems.
• Using special features like pciback may be problematic. Do not implement these
when deploying for an environment that should migrate VM Guest systems between
different VM Host Server systems.
• For fast migrations, a fast network is mandatory. If possible, use gigabit ethernet
and fast Switches. Deploying vlan might also help avoiding collisions.
4.6.1 Configuring Xend for Migrations
To prepare a VM Host Server system for migrating, edit the configuration file /etc/
xen/xend-config.sxp. Search for the following lines:
#(xend-relocation-server no)
#(xend-relocation-port 8002)
(xend-relocation-hosts-allow '^localhost$ ^localhost\\.localdomain$')
Change the lines to match the following strings:
(xend-relocation-server yes)
(xend-relocation-port 8002)
(xend-relocation-hosts-allow '')
These changes must be done on all VM Host Server systems that should participate in
migrating guests.
Managing a Virtualization Environment 37