EFS Systems on a Linux Base: Getting Started

4 EFS Systems on a Linux Base: Getting Started

terminals. z/OS TCP/IP is not involved in these functions and need not be running. These

local 3270 terminals are the most basic z/OS terminal and z/OS is unaware they are

actually remote TN3270e terminals.

򐂰 Client workstations, using 3270 emulators, can connect to z/OS TCP/IP (assuming it is

configured and running). This interface can be used for normal VTAM purposes (such as

TSO) but not for traditional operator consoles.

򐂰 Other z/OS TCP/IP functions, such as FTP, Telnet, a Web server, and so forth, function

normally through this interface. If UNIX System Services Telnet is active, a remote user

could connect to this interface.

An important point is that all these connections can operate simultaneously through a single

physical LAN interface to the EFS system. If used as described, this interface has two IP

addresses: one for Linux and one for z/OS.

Figure 1-2 Multi-user System

With the configuration shown in Figure 1-2, a typical client might use a Windows-based

mobile computer connected to the LAN. PCOM

3

can provide 3270 sessions that appear as

locally-connected, non-SNA sessions to z/OS (if connected through the Terminal Solicitor) or

as z/OS TCP/IP TN3270 connections. The distinction is made by which IP address and port

number the client uses for the EFS connection. These sessions can be used for z/OS

operator consoles or VTAM applications such as TSO, CICS, and so forth. The Telnet

application provided by Windows can be used to connect to Linux on the ThinkPad EFS

system (if such access is enabled) or to z/OS UNIX System Services (if this access is

enabled). If properly enabled, the client systems can FTP to Linux or z/OS, connect to a Web

server under z/OS, and so forth.

The EFS

host system in this illustration could be a ThinkPad, a desktop PC, or a large xSeries

server.

1.4 Basic EFS requirements

Key points in understanding hardware requirements are:

򐂰 No unique hardware is used for z/Series emulation. There is no “S/390 adapter.”

Everything is software, with these exceptions:

3

PCOM is the common name for the IBM eNetwork Personal Communications product. It provides TN3270e client

functions.

EFS System

LAN

ThinkPad

ThinkPad

Desktop

PCOM, Telnet, or both

Windows

OS/2

Linux

x3270

Desktop

PCOM

PCOM

Windows

Telnet

z/OS running

under FLEX-ES

Two IP addresses:

one for Linux TCP/IP,

one for z/OS TCP/IP