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

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Name Resolution B-5
B
When the Sun Name Server receives a name resolution request, it assumes that
the name is an SNA resource (PU, LU, or LU pool) and checks its resource
database for the name. If the name is not an SNA resource, the Sun Name
Server then checks its user database for the name.
If the client requests an LU pool, the Sun Name Server performs load
balancing, returning the addresses of all the systems that contain available LUs
in the requested pool. The Sun Name Server ranks the systems so that the
system with the smallest load, the highest available bandwidth, and, if the
network is configured appropriately, in the most suitable geographical location
is presented first. For more information about load balancing, refer to
Appendix E, “Load Balancing."
Note – The local DNS may reorder the addresses returned by the Sun Name
Server so that addresses on the local subnetwork are presented before
addresses on a remote subnetwork. In addition, since identical requests for a
pooled LU could resolve to different system addresses depending on
prevailing load conditions, the local DNS cannot cache the SNA domain
information. To prevent caching, the Sun Name Server returns a TTL of zero.
B.3 Updating the DNS Configuration
If your environment is already running a DNS, you must modify the DNS
configuration to ensure that the DNS is aware of the subdomain controlled by
the Sun Gateway Manager SunGMAN). (This subdomain is called
Sun
by
default.) If your environment is not running a DNS, you can use the DNS
contained in the SunGMAN as a primary DNS for the
Sun
subdomain.
If the SunGMAN installation procedure detects that a DNS is already
configured, the SunGMAN automatically configures itself as a secondary DNS.
The installation procedure also reports any changes that you must make to
your primary DNS to incorporate the Sun subdomain into the DNS
environment.