HP-UX HB v13.00 Ch-10 - Network Services

HP-UX Handbook – Rev 13.00 Page 4 (of 26)
Chapter 10 Network Services
October 29, 2013
Introduction
This document is a short introduction to some commonly used network services on HP-UX
systems. It is not intended to be an exhaustive survey of services. Since most, if not all, network
services rely heavily on solid and consistent name resolution, this is addressed first. This is
followed by a general description of some commonly seen network services.
Host Based Network Support
Name Resolution
A central service being used by almost every program is name resolution, the correlation
between names and IP addresses. The functions gethostbyname() and getnamebyaddr()
(implemented within libc) are the basis of this service in a IPv4-only environment. In the dual
stack IPv4-IPv6 environment found in HP-UX 11iv2 and higher these are replaced by
getipnodebyname() and getipnodebyaddr() functions.
These basic functions can use different information sources:
 the local file: /etc/hosts
 the Network Information System (NIS, previously called “Yellow Pages”)
 the Domain Name System (DNS)
 Lightweight Directory Access Protocol (LDAP)
Rarely, there may be a NIS+ configuration on HP-UX on versions prior to HP-UX 11.31; it is,
however, a dead technology. In such a configuration, /etc/nsswitch.conf would contain the
service switch nisplus.
NIS is still available on all supported versions of HP-UX and is still used by customers (even
some large customer environments) but suffers from scalability issues that make it undesirable
for large enterprise environments. For common necessary unix information such as UID, GID,
and GECOS information in a large enterprise environment, LDAP is the de facto industry
standard.
For hostname-only information DNS would be still be considered the de facto industry standard.