Database Software

hello all,

I am new to RAC , one of my client want to implement first a test inviromement of RAC. He has 3 servers(2 cpu each), he will be using RHEL ES 4 as OS. He want use 2 server for RAC nodes and one server (80GB hard disk ) as a shared storage.

So my question is that can we use simple hard disk storage as a shared storage in RAC or we have to use SAN or NAS storage box?

Thanks In advance!!