HP-UX IPv6 Transport Administrator's Guide for TOUR 1.0

Configuration
Host Names and IPv6 Addresses
Chapter 3 25
Or if /etc/hosts is to be the primary Name Service, the entry should be
set as follows:
ipnodes: files [NOTFOUND=continue] dns
IMPORTANT If you have an /etc/nsswitch.conf file, and if you have set a hosts
entry in that file, then you must set a similar ipnodes entry. You must do
this even if you do not use IPv6 addresses. Also, be aware that you
cannot use NIS or NIS+ on the ipnodes entry.
Manually editing nsswitch.conf
If the current system has no nsswitch.conf file, use a text editor to
create an /etc/nsswitch.conf file containing the following line, or copy
the /etc/nsswitch.defaults file and modify as needed.
Refer to the nsswitch.conf(4) man page for hosts syntax.