Somewhat dated and non-standard approach (no real MPI or HPC coverage). Examples use four node cluster with 10BT Ethernet connected with a small hub. (264 pages) ISBN 0-672-32368-0 Seems to be out or print.
Linux Cluster Architecture by Alex Vrenios
http://www.amazon.com/exec/obidos/tg/detail/-/B0009EK80O/ref=pd_sim_b_1/104-1154502-8274348?%5Fencoding=UTF8&v=glance