gtpm1m13TPF V4R1 Migration Guide: 3.1 to 4.1

ACF/SNA Table Generation Support

In the TPF 3.1 system, to install new network definitions, you had to bring down the network, cycle down all the processors in a loosely coupled complex, and load the pilot tape. Offline ACF/SNA table generation (OSTG) could only write network definitions to tape in a pilot tape format. After loading the pilot tape, all processors had to be IPLed and then cycled back up to NORM state. The resource resolution table (RRT) contained only one set of network definitions.

In the TPF 4.1 system, OSTG allows you to write network definitions to tape or general data sets (GDSs). The new dynamic load function allows you to load SNA resource definitions without deactivating the network and cycling all processors to 1052 state. If you find problems with the new network definitions, you can fall back to previous definitions, regardless of how many CPUs have incorporated the new definitions. You can perform all of these tasks by using the new ZNOPL command.

When you enter the ZNOPL LOAD command, the TPF 4.1 system takes the network definitions from the tape or GDS and loads them into the resource resolution table (RRT). RRT entries are processor shared; there is only one set of RRT entries for all processors in a complex. You can enter the ZNOPL command from any processor in a loosely coupled complex, in any system state, to perform either fresh or dynamic loads.

In the TPF 4.1 system, the RRT contains up to two sets of network definitions and is divided into two tables:

The existing RRT contains the current SNA resource definitions, while the new RRT contains the new ones.

In a fresh load, the existing RRT is initialized with the contents of the SNA tape or GDS. A fresh load causes SNA restart to create and initialize all of the TPF SNA control blocks, such as resource vector tables (RVTs), node control blocks (NCBs), and the subarea address table (SAT), during a soft IPL.

In a dynamic load, the new RRT is created for the new resources. A dynamic load allows you to enter new network definitions into the TPF 4.1 system without bringing down your network, communication controllers, or network control programs (NCPs). A dynamic load creates and initializes only the SNA control blocks for the new resources. It does not change the control blocks for the resources that existed before you performed the dynamic load. You can perform a dynamic load in any TPF system state while the network is active. To perform a dynamic load, enter the ZNOPL LOAD command with the DYNAMIC parameter specified.

For loading SNA definitions, the ZNOPL LOAD command replaces the ZSLDR LOAD DATA command. (The ZSLDR LOAD DATA command is still used for loading other pilot tapes.)

See the TPF ACF/SNA Data Communications Reference for more information about the dynamic load function. See TPF Operations for more information about the ZNOPL commands.

See Defining Systems Network Architecture (SNA) Resources for information about how to define SNA resources using fresh and dynamic loads.