Sun Microsystems SunLink SNA 9.1 PU2.1, Руководство по настройке

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Name Resolution B-7
B
nameserver 199.97.127.10
nameserver 199.97.127.20
Some domain name servers support a
search
directive to override the
default order in which domains are searched. Referring to Figure B-2, to
query
acme.com
before the default domain
corp.acme.com
, the
resolv.conf
file would contain the following
search
directive:
search acme.com corp.acme.com
To minimize the impact of introducing DNS, your client systems should, if
possible, be configured to use the Sun Name Server to attempt name resolution
after the usual name resolution schemes have failed.
In small sites, LAN-wide names are resolved by system files, which are copied
among all the machines on the LAN. These files include
/etc/hosts
,
/etc/services
, and
/etc/passwd
, which contain the mappings of host names
to IP addresses, the mappings of service names to TCP and UDP port numbers,
and user information, respectively. All systems use the
/etc/hosts
file if DNS
fails to resolve a host name.
The most popular alternative to DNS is Sun’s Network Information System
(NIS), which is distributed by most Unix vendors. NIS maintains the system
files in synchronization across the networked systems. The files are
administered on one master system and distributed among the slaves by NIS.
An NIS resolver (implemented as part of the
ypserv
program) performs name
mapping.
Depending on your operating system, you can configure systems to resolve
host names using the local
/etc/hosts
file, NIS, and/or DNS in one of the
following ways:
•
Solaris - Uses a control file,
/etc/nsswitch.conf
, to specify the order in
which the
/etc/hosts
file, NIS, and DNS are queried to resolve names.
Hosts running the Sun Name Server must specify
files
before
dns
in the
/etc/nsswitch.conf
file. For efficiency, Sun recommends that Solaris client
systems also specify
files
before
dns
in the
/etc/nsswitch.conf
file.
B.4 Using the Sun Name Server with APPC
SUNWappc TPRM programs issue the
lu62_open()
call to connect to a server
and local LU. Assuming that the Sun Name Server domain is
sna
and the local
LU is
LUSP1
, the call is issued as follows: