Installing Entire System Server Interface on z/OS

The Entire System Server Interface is required if the Entire System Server or Natural ISPF is to be used.

This document describes the steps for installing the Entire System Server Interface on z/OS. You can choose between default installation (recommended) and customized installation.

Related Topic:

For information on installing and using the Entire System Server or Natural ISPF, refer to the relevant product documentation.

Notation vrs or vr:

When used in this document, the notation vrs or vr represents the relevant product version (see also Version in the Glossary).


A supported version of either of the following products must be installed before you can install the Entire System Server Interface:

See also General Prerequisites and System Support in the section Overview of the Installation Process.

Default or Customized Installation

If you want to use the default value settings in the modules ESYNODTB and NATPNIP (used by the Entire System Server and Natural ISPF), proceed with Link the Entire System Server Interface to the Nucleus.

If you do not want to use the default value settings, edit the modules NATPNIP and ESYNODTB described in this section.


The NATPNIP module contains the following parameters and default values:


The parameters are explained below:

BUFLEN Length of all Adabas buffers in bytes
NUMREQ Number of possible nested FIND loops in Natural calling the Entire System Server
MAXCBL Complex FIND buffer length
MAXEDL Editor session buffer length

MAXEDL is used by the NSPF editor and incore database.

The default value is 6000, which should be sufficient for an NSPF editor session and typical incore database applications. However, for large layouts within an incore database file that value might not be large enough and the following message is issued: NAT3077: Not enough space for extent. DB/FNR/Subcode :1:/:2:/:3:. (see the Messages and Codes documentation).

In this case, the value of MAXEDL has to be increased.

EXTUSER External user ID passed to the Entire System Server for security checks

See also EXTUSER in the following section.


The parameter EXTUSER describes how to inherit security definitions from an external security system such as RACF, ACF2 and TOP-SECRET.

The appropriate parameter setting depends on whether a multi-user address space or a single-user address space is used in your environment:

  • A multi-user address space provides the option to maintain different user security definitions, for example, one for a CICS and one for a Com-plete user).

  • A single-user address space supports a subsystem, for example, a Natural subtask for Entire Output Management or Entire Operations Management, or a Natural RPC, Natural Web/IO Interface or batch server.

    Recommended values for EXTUSER are:

    EXTUSER=INIT-USER Recommended for a multi-user address space.

    The contents of the Natural system variable *INIT-USER must be identical to the user definition in the external security system (for example, RACF).

    The Entire System Server transfers the value of *INIT-USER to the external security system, and all calls to security restricted resources are handled under this user ID.

    In this case, the security definition from a CICS or Com-plete user (for example) is inherited by Entire System Server, and a new logon is not required. If the value of *INIT-USER is not found in RACF (for example), an error occurs indicating that a logon is required.

    (*INIT-USER is described in the System Variables documentation.)

    EXTUSER=USER Recommended for a multi-user address space in a Natural Security environment.

    Processing is similar to EXTUSER=INIT-USER except that the Natural system variable *USER (described in the System Variables documentation) is used.

    (*USER is described in the System Variables documentation.)


    Recommended for a TSO, batch or server environment.

    The security description of this address space is inherited for security evaluation.


The ESYNODTB module contains the following parameters and default values:


The parameters and default values are explained below:

ID Entire System Server node number (also known as DBID)
NAME Entire System Server node name
LAST Indicator for last entry in table

Optional Node Name for Entire System Server Calls

Calls to the Entire System Server from Natural are usually handled with the NODE parameter which specifies the node number to be used for the call, for example:


If the node number is defined in the ESYNODTB module, alternatively, you can specify the logical name of the required Entire System Server with the NODE-NAME parameter, for example:


Assemble the Parameter Module for the Entire System Server Interface Component

Natural ISPF

If Natural ISPF is used as the INCORE database:

  • (Job I055, Step 1106)

    Link the parameter module NATPNIP. In this case, the module ESYNODTB is not required.

Entire System Server

If the Entire System Server is used:

  • (Job I055, Steps 1106, 1107)

    Assemble and link the modules NATPNIP (Step 1106), and, optionally ESYNODTB (Step 1107).

Link the Entire System Server Interface to the Nucleus

(Job I060, Step 3720)

  • Link the following Entire System Server Interface modules to either the environment-independent nucleus or the environment-dependent nucleus by using the corresponding INCLUDE statements:

    Entire System Server Interface parameters
    Entire System Server Interface module
    Optional, node table

Installing and Activating the Write-to-Spool Feature

If you want to use the Write-to-Spool feature, either link the access method to your nucleus or load the method dynamically. See also the Natural parameters RCA and RCALIAS.

You can define and assemble the defaults for your nucleus by using the source member NATPWSDF before linking the defaults to the nucleus. You can find the source member NATPWSDF in the source library of Natural.

The default settings of source member NATPWSDF are as follows:


The table below shows the modifiable parameters of source member NATPWSDF and a detailed description of these parameters:

Parameter Description
Node NPR target node.

The node number can consist of up to 5 digits.

It addresses the destination started task of the Entire System Server and where the output is written.

Program JES Writer which can contain up to 8 characters.

JES provides control to the Writer program. If JES does not find it, it is ignored.

Possible value: *OUTPUT means that the input from the Natural statement DEFINE PRINTER is used to be interpreted as JES Writer.

Class SYSOUT class within JES where the output has to be written. It can contain only one character or digit.

It is a descriptor for further software (for example, Entire Output Management) to detect the output stream for processing.

Hold = yes/no Specifies whether the output stream is to be held within the JES spool in case the task previously started by the Entire System Server terminates.
Represents the control character for the SYSOUT data set.

CNTL contains one character:

A ASA control character
M Machine control character
FormRMT Describes the form control buffer for JES. This value is transferred to JES which handles the processing.

RMT represents the JES remote user ID if SYSOUT has to be routed to a different JES system.

You can find the name of the JES system in the destination field within the DEFINE PRINTER statement (for example, DEFINE PRINTER OUTPUT='DAEM').


Can contain up to 6 characters.

After editing the NATPWSDF source member with customized values, you can assemble and link it. If you want to use the default settings, you can omit this step.

If you want to use the Write-to-Spool feature with statically linked access method at your site, relink the Natural module as follows:

INCLUDE NATLIB(NATPWSPL)     The Write-to-Spool access method for Natural
INCLUDE NATLIB(NATPWSDF)     The Write-to-Spool defaults
                             (your adapted parameter module)

If you want to use dynamic load, you can either use the delivered module NATPWSAM with default parameters or you can link your adapted parameter module:

INCLUDE USRLIB(NATPWSPA)     Your adapted module
NAME NATWSPvr(R)             Your adapted Write-to-Spool module.
                             This name must be used in RCALIAS=(NATAM11,NATWSPvr).

For further information, see System Spool Access in the Operations documentation.

Install the Entire System Server in Single-User Mode

(Optional installation for batch mode or TSO only)

This section describes the advantages of Entire System Server in single-user mode and the steps required for installation.

Advantages of Single-User Mode

Running the Entire System Server in single-user mode is advantageous, for example, in the following cases:

  • Executing long running batch jobs comprising a large number of calls to the Entire System Server.

  • Performing test scenarios using a Natural session under TSO performing many calls to the Entire System Server, without disturbing the production environment.

  • Exploring new Entire System Server functionality or versions.

From a Natural point of view, the Entire System Server single-user mode is accessible as Entire System Server node 148, irrespective of whether such a node does already exist on your machine or network.

The following is an example of a Natural program that is running in a single-user environment:


This statement calls a single-user Entire System Server that runs within the same address-space. Calling a different Entire System Server node that runs elsewhere in the network is possible by using a different node number, as shown in the following example:


This statement calls a multi-user Entire System Server with node number 53 out of the same Natural program which called the single-user Entire System Server session.

Installation for Batch Mode

  1. Create a new PDS load library, which must be APF-authorized.

  2. Copy all members of the Entire System Server load library into the new load library.

  3. Link the module NATPSNGL, which handles Entire System Server single-user features, to the environment-dependent nucleus for batch Natural.

    Alternatively, you can use the RCA parameter to dynamically load this module by setting RCA=NATPSNGL.

    In both cases, the environment-dependent nucleus must be authorized by parameter AC=1 and linked into the new load library.

  4. Add the mandatory cards PARMS and SYSPRINT to your JCL to handle the Entire System Server-relevant steps. In addition, you can add the optional cards ESYTRACE and CLOG.

    //ESYTRACE DD  SYSOUT=*             Internal trace
    //SYSPRINT DD  SYSOUT=*             Modules/Zap directory of Entire System Server
    //CLOG     DD  DISP=SHR,DSN=xxx     Command log data set
    //PARMS    DD  DISP=SHR,DSN=xxx     Entire System Server parameter
  5. Add an Adabas load library to your JCL, which also has to be APF-authorized.

  6. Edit your Entire System Server parameter member. Here, the parameter NODE will be ignored, since Natural routes any calls to node number 148 through to the single-user Entire System Server node.

Installation for TSO

  1. Add the name of the nucleus as AUTHPGM in the TSO definition member named IKJTSO00. Usually, this member is in data set SYS1.PARMLIB.

  2. Proceed analogously as described in the batch mode installation above.