HP-UX IPv6 Transport Administrator's Guide (September 2004)

Configuration
Host Names and IPv6 Addresses
Chapter 2 21
3ffe:ffff:101::230:6eff:fe04:d9ff host3 host3.site2.region4
192.1.2.34 hpfcrm loghost
NOTE HP-UX IPv6 release is a dual stack implementation. A single host name
can have entries for both an IPv6 address and an IPv4 address in
/etc/hosts.
Name and Address Lookup for IPv6
/etc/nsswitch.conf (nsswitch.conf(4)) is a configuration file for the
name service switch. The ipnodes entity specifies which name services
resolve IPv4 and IPv6 addresses and host names.
More specifically, the ipnodes keyword specifies the resolver policy for
the library functions getnameinfo(3N), getaddrinfo(3N),
getipnodebyname(3N) and getipnodebyaddr(3N) for both IPv4 and
IPv6 addresses. The existing keyword “hosts” specifies the resolver
policy for the library functions gethostbyname() and gethostbyaddr()
for IPv4 addresses.
NOTE Internet Services applications (such as telnet, r-commands, etc.) use
these library functions to resolve IPv4 and IPv6 addresses.
By default, the /etc/nsswitch.conf is not on the system. The default
ipnodes policy (same as default hosts policy) is as follows:
dns [NOTFOUND=return] files
This policy implies that dns is the authoritative resolver and will only
try files if dns is down. If dns is available but returns NOTFOUND, the
search stops.
Thus, if DNS has not been set up as the definitive source, and files
(/etc/hosts) may need to be used for address and host name resolution,
HP recommends adding the following entry to /etc/nsswitch.conf:
ipnodes: dns [NOTFOUND=continue] files
Or if /etc/hosts is to be the primary Name Service, the entry would be
set as follows: