This is not definitive list but as a simple task you will need to make sure that all your servers have the right OS version, all dependency packages are installed and finally that the right Openstack code (projects like nova, cinder, etc) are deployed This list is only as very simple example what you need to think about. As a demonstration in this blog I wanted to show an example how this can be achieved with a Puppet razor tool.
How to provision and configure Openstack servers.
Analysis and results description
Openstack+puppet+razor: all details of how to run this can be found here: http://wiki.debian.org/OpenStackRazorHowto