TN3270 Server Manual

Introduction to the Guardian TN3270 Server
TN3270 Server Manual—424097-001
1-2
Clients
Guardian TN3270 Server can run as either a single process or a NonStop process pair. A
startup option specifies which configuration to invoke and which CPU to use as the
backup processor when running in NonStop mode. When operating in the NonStop
mode, the primary process records dynamic data to the backup processor. If the primary
process or processor fails, the backup process takes over immediately and continues
Guardian TN3270 Server support.
Guardian TN3270 Server has the following restrictions:
•
The maximum number of windows that can be added is 1000.
•
The NonStop operating system limit on the number of concurrent I/O operations
pending from applications to Guardian TN3270 Server is 2048.
•
The maximum number of opens from all applications, including TN32COM, to
Guardian TN3270 Server is 1005.
•
In NonStop mode, all active sessions assume a disconnected state if the primary
process or processor fails.
Guardian TN3270 Server does not support the following features:
•
ISO 8859/0 character sets
•
RFC 1041 (3270-Regime)
•
Exclusive opens of Guardian TN3270 Server
Clients
Guardian TN3270 Server clients are available for a wide variety of platforms, including
MS-DOS, Apple, DEC, IBM, and most UNIX systems. You can obtain TN3270 clients
from your LAN vendor, workstation vendor, or a third party.
Note. When configuring Guardian TN3270 Server, you must consider the maximum number of
openers and the nowait depth used by the application. The Tandem NonStop operating system
allows each opener to have up to 15 nowait I/Os pending. This restriction can cause problems
if more than 136 openers all post 15 nowait I/Os (137 openers x 15 I/Os = 2055 concurrent
I/Os).