Note: this page is out of date as of 8/2011; it describes the cluster topology as of June 2011:

The rcmaster machine is the only one accessible from the Stanford network and the Internet. It serves as our gateway to the cluster nodes, and we run our development tools on it. Each host mounts /home from the NFS server (named rcnfs), so it's easy to build on rcmaster and execute the resulting binaries on rc01 through rc40.