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

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Overview 1-11
1
For independent LU-LU sessions, either independent LU can initiate the
session. In addition, multiple sessions, known as parallel sessions, can be
established between two independent LUs.
For both SSCP-LU control sessions and LU-LU application sessions, the Sun
PU2.1 SNA Server enforces the SNA protocols.
For more information about configuring dependent LUs, refer to Chapter 8,
“Configuring Dependent LUs.” For more information about configuring
independent LUs, refer to Chapter 9, “Configuring for LUType 6.2.”
1.7 LU Pools
LU pools are groups of dependent LUs that are accessible to certain users. If a
user specifies an LU pool name instead of an LU name, the Sun PU2.1 SNA
Server assigns the user to one of the dependent LUs in the LU pool. All
dependent LUs in a particular LU pool must be of the same type (all LUType
0, all LUType 1, all LUType 2, all LUType 3, or all LUType 6.2).
Although you can assign any type of dependent LU to an LU pool, LU pools
are most commonly used for LUType 2 dependent LUs for access by 3270
clients.
You can provide redundancy by distributing an LU pool across multiple
systems. If some of the systems are removed from operation, the remaining
systems can still accept new client connections.
If the LU pool is distributed across multiple systems, the server uses load
balancing to direct the client to the system with the lightest load, with the
highest available bandwidth, and with available LUs. In addition, if the
network is configured appropriately, the server can direct the client to the
system in the most suitable geographical location. For more information, refer
to Appendix E, “Load Balancing.”
LU pools are also useful for the following:
•
You can simplify user access by providing all users with a single LU pool
name, instead of providing each user with a separate dependent LU name.
Users are isolated from configuration changes.
•
You can maximize the use of host resources by defining only enough host
dependent LUs to meet your peak usage. Note, however, that defining
additional resources ensures adequate availability if a system or connection
fails.