HP-UX IPv6 Transport Administrator Guide HP-UX 11i v3 (5992-6426, May 2013)

5 IPv6 Software and Interface Technology
The topics discussed in this section concern IPv6 deployment and migration.
Name and Address Lookup for IPv6
It is generally recommended to add IPv6 addresses (known as AAAA records) to a DNS
Name Server only when the following conditions are true:
• The IPv6 address is assigned to the interface on the node.
• The address is configured on the interface.
• The interface is on a link which connects to the IPv6 infrastructure.
HP recommends beginning with IPv6 addresses and host names in the /etc/hosts file
on a development network; then adding IPv6 addresses and hosts to a Domain Name
Service when moving IPv6 to a production backbone network.
/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 on HP-UX 11i.
More specifically, on HP-UX 11i v2, the keyword ipnodes 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
functionsgethostbyname() and gethostbyaddr() for IPv4 addresses.
NOTE: On HP-UX 11i v2, 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 a 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
ipnodes: files [NOTFOUND=continue] dns
NOTE: You can not specify NIS or NIS+ on the ipnodes entry.
Name and Address Lookup for IPv6 53