Jeffrey Hunter has published an insightful article about building an Oracle RAC 10g R2 Cluster with less than $1,800. If you are struggling to maintain an Oracle RAC at your work, do take a look. The system involved comprises a dual-node cluster (each with a single processor) running Linux (CentOS 4.2 or Red Hat Enterprise Linux 4) with a shared disk storage based on IEEE1394 (FireWire) drive technology.
