TN3270e Server Manual
Introduction to the TN3270e Server
TN3270e Server Manual—422923-003
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Features
The TN3270e server runs as a subtype 30 device and emulates the SNAX/XF
interface.
The TN3270e server returns to HP applications calling DEVICEINFO, a device type
and subtype corresponding to its configuration. The device type returned depends on
the current screen protocol of block (CRT) protocol or interactive terminal interface (ITI)
protocol. The subtype returned depends on the terminal type negotiated during Telnet
option. If DEVICEINFO is called before option negotiation has completed, the TN3270e
server returns the type and subtype for an IBM 3278-2 for the application interface
specified at startup. Appendix A, Terminal Models in SNAX/XF Mode lists terminal
models recognized, and the corresponding device types.
The TN3270e 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 TN3270e server support.
The TN3270e server has the following restrictions:
The maximum number of windows that can be added is 1000.
The NonStop OS limit on the number of concurrent I/O operations pending from
applications to the TN3270e server is 2048.
The maximum number of opens from all applications, including ETN32COM, to the
TN3270e server is 1005.
In NonStop mode, all active sessions assume a disconnected state if the primary
process or processor fails.
Note. The AM3270 interface supported by the traditional Guardian TN3270 server process is
not supported by the TN3270e server process.
Note. When configuring the TN3270e server, you must consider the maximum number of
openers and the nowait depth used by the application. The NonStop OS 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).