Interoperability with IBM Host Systems
Interoperability with IBM Host Systems |
|
In most cases, deployment strategies are effective for APPC LUs regardless of the application that the LUs support. When deploying APPC connections with SNA Server, you should consider how to use the following types of LUs and LU configurations:
An independent LU can communicate directly with a peer system and does not need the support of a host computer. Independent APPC LUs, as used in AS/400 APPN networks, provide the ability to run multiple, concurrent, parallel sessions between a local and remote LU pair.
When configuring independent APPC LUs, you should note that when SNA Server is used to communicate with a TP on a mainframe over an independent APPC LU, the host system must be running VTAM V3R2 or later. The version of Advanced Communication Function/Network Control Function (ACF/NCP) required on the mainframe is dependent on the type of FEP used. For 3725 systems, ACF/NCP V4R3 or later is required. For 3745 systems, ACF/NCP V5R2 or later is required.
For information about configuring independent APPC LUs, see the SNA Server version 4.0 documentation.
A dependent local APPC LU requires the support of a mainframe to communicate with a remote TP. Dependent APPC LUs cannot be used to communicate with AS/400s. Unlike independent APPC LUs, dependent APPC LU only allow one session per LU.
Dependent APPC LUs are useful when configuring SNA Server to communicate with a mainframe using a version of VTAM earlier than V3R2 because independent LUs are not supported in earlier VTAM versions. SNA Server provides support for dependent APPC LUs. However, use independent LUs whenever possible.
When configuring APPC dependent LUs, you should specify the network name and LU name, even though they are not required. They are used by software running on the SNA Server–based computer, such as the Windows 2000 event log. For example, if a remote APPC LU is partnered with a dependent local APPC LU, naming the remote APPC LU helps to identify any events associated with it in the Windows 2000 event log.
For more information about configuring dependent APPC LUs, see the SNA Server version 4.0 documentation.
Although you can create individual LUs and assign them to users and groups, using LU pools to manage and deploy a large number of LUs lets you administer these resources more efficiently.
LU pools also allow groups of intermittent users to use a limited number of host resources more efficiently. Dedicating LUs to specific users who occasionally require host access wastes host resources. Using a pool, you can assign a smaller number of LUs to a group of users who require sporadic access. For example, if a group of 100 users require host access 25 percent of the time, assigning a pool of 25 LUs to the group might meet their requirements.
For information about configuring LUs, see the SNA Server version 4.0 documentation and the Microsoft® BackOffice® Resource Kit.