After installing the Red Hat Virtualization components, you must reboot the system. When the boot completes, you must log into your system as usual. Then before you start Red Hat Virtualization you must log in a root. The xend control daemon should already be initiated by initscripts, but to start the xend manually, enter:

service xend start 

You can also use chkconfig xend when installing to enable xend at boot time.

The xend node control daemon performs system management functions that relate to virtual machines. This daemon controls the virtualized resources, and xend must be running to interact with virtual machines. Before you start xend, you must specify the operating parameters by editing the xend configuration file xend-config.sxp which is located in the etc/xen directory.