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

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Name Resolution B-3
B
The local name server then reissues its query to the next-level name server, and
so on. When the requested host is located, the local name server returns the
name and network address of the host to the client. If a name is not fully-
qualified, the local name server expects the name to be (or to be in) one of its
own subdomains.
As a name is resolved, the local name server can temporarily store (cache) the
information it discovers about the name space, speeding up subsequent
queries and reducing the dependence and load on the higher-level name
servers (particularly the root name servers). To prevent name servers from
caching data indefinitely, the resolving name server returns a time-to-live
(TTL) value for the data it returns. The data is purged from the cache when the
TTL expires.
For more information about DNS and domain administration, refer to the
network administration documentation provided with your system or to DNS
and BIND by Paul Albitz and Cricket Liu, published by O’Reilly and
Associates.
B.2 Sun Name Server
Note – Before you can use the Sun Name Server, you must update the DNS
configuration. For more information about how to update the DNS
configuration, refer to Section B.3, “Updating the DNS Configuration,” on
page B-5
Note –
You cannot run the Sun Name Server on a system that is running
another DNS. In addition, the Sun Name Server cannot replace another DNS.
Since the Sun Name Server is customized to handle a Sun SNA domain, it
cannot resolve name requests to other domain name servers.
A client connects to the host by specifying the name of the resource it wants to
access (resource selection) or by specifying its user name (user mapping). If the
client adds the name of the Sun subdomain as an extension to the resource or
user name, such as
LU010A.sna
or
jdaniels.sna
, the client instructs the local
DNS to defer the resolution of the name to the Sun Name Server.
Resource selection and user mapping are described as follows: