I also read the bock of Knopper which I find a good for understanding. If you want more concrete details about the redhat cluster suite read the RedHat documentation: http://www.redhat.com/docs/manuals/csgfs/browse/rh-cs-en/ (you can also get it in pdf format but I did not find the link anymore. If you want it I can send it to you). Some documentation in the same style can be found on Wikipedia: http://gfs.wikidev.net/Installation. Maybe the FAQ can help you too: http://sources.redhat.com/cluster/faq.html.