In this chapter, we explored Sun's Remote Procedure Call interface, the fundamental building block on which both Sun's Network Information System (NIS) and Sun's Network Filesystem (NFS) are based. RPC is ubiquitous, yet many of its users do not understand the security implications that are inherent in its operation.
If you run NFS or NIS, then you are running RPC. Be sure that the version you are running is up to date, properly installed, and secure against external attack. And if you are running Secure RPC, you should investigate transitioning to newer products that are more widely used and subject to greater security auditing.