The "official" instructions how to install openstack components are located here:
Unfortunately they are not very clear and miss some key points. Below is summary of our installation procedure.
First of all, let us install worker node.
rpm -ivh openstack-repo-2011.2-1.el6.noarch.rpm
yum install libvirt
chkconfig libvirtd on
yum install openstack-nova-compute openstack-nova-compute-config
service openstack-nova-compute start
If everything goes fine you should see
Starting OpenStack Nova Compute Worker: [ OK ]