SAP Configuration

CPI-C connections are referenced via logical destinations (symbolic destinations). These destination names can be freely chosen by the user. The allocation of these symbolic destinations to real connections with LU and TP takes place in the side-info files.

The SAP environment contains the following side info files:

XCOM

R/2 table for all connections initiated (established) from R/2.

TXCOM

R/3 table for all connections initiated (established) from R/3.

sideinfo

Unix file system file under (/usr/sap/<SID>/<INST>/data), required by the SAP gateway and possibly by external C programs as well

CUA Interface

Only one sideinfo file is required. No XCOM or TXCOM table.

The CUA Interface is comparable with a CPI-C connection to R/2. A destination is assigned to each R/2 system (e.g. K50). All CUA users who work in parallel must have their own destination (K50_1, K50_2, K50_3...) in the sideinfo. The IBM SNA-Server/6000 does not take care of the LU pooling in this case. Therefore every possible connection (destination name with _1, _2, _3...) has to be defined in the sideinfo. The LU pooling is taken care of by the SAP gateway. For dependent LU6.2 an LU (name of the sideinfo profile from the IBM SNA-Server/6000 configuration) must be assigned for every destination entry in the sideinfo.

R/2-R/3 Connections

For an R/2-R/3 connection the active partner, i.e. the partner that establishes the connection, must be identified.

Connection from R/3

If the connection is established from the R/3 side, then a TXCOM table and a sideinfo file are required in the R/3 system. Only one entry is required (without _1, _2...) in the TXCOM for each destination (R/2 to target system). In the sideinfo the same entries are needed as for the CUA interface. Here too a destination is required in the sideinfo for each connection that is to be established in parallel.

Initiating the Connection From R/2

If the connection is established from the R/2 side, then a XCOM table and a sideinfo file are required in the R/2 system. One entry for each connection is needed in the XCOM. In this case, LU is the LU name in CICS and TP is the name of the partner transaction on the UNIX side. SAP supplies the "gwhost" program for this purpose. The gwhost program is able to establish a connection to any R/3 system, according to the configuration in the sideinfo. However, in order to distinguish between the different connections, the gwhost program must be addressed via differing symbolic links. The name of each symbolic link should contain the name (SID) of the R/3 target system (e.g. GWHSTC11). After the gwhost program is started, it searches for the sideinfo file in the home directory of the user (user-id) under which the program was started (see local_tp-profile of the SNA-Server/6000). In the sideinfo file the program now searches for a destination having the same name as the name under which the program was called (symbolic link GWHSTC11).

Example:

  1. XCOM entry with TP=GWHSTC11
  2. Definition of the local_tp in SNA for GWHSTC11
  3. Symbolic connection of the GWHSTC11 to /usr/sap/C11/SYS/exe/run/gwhost
  4. sideinfo in the home directory of the user id that is defined under local_tp in SNA.
  5. Entry in the sideinfo with DESTINATION=GWHSTC11

External Programs

You also have to identify the active partner in this case.

A sideinfo entry (e.g. K50) is needed for a connection through an external program on Unix via TCP/IP to the SAP gateway and from there via SNA to R/2. The external program uses this entry to determine the SAP gateway (GWHOST and GWSERV parameters). The SAP gateway then searches the sideinfo entries K50_1, K50_2, K50_3,... for the next free SNA connection to K50 (LU pooling).

A sideinfo entry (e.g. K50) is also needed for a connection through an external program on Unix directly via SNA to R/2. The external program determines the SNA connection (LU und TP) from this entry. There is no LU pooling.

A sideinfo entry (e.g. C11) is needed for a connection through an external program on Unix via TCP/IP to R/3. The external program uses this entry to determine the SAP gateway (GWHOST and GWSERV parameters). The SAP gateway then uses the same sideinfo entry to determine the "R/3 entry point" (Host name and dispatcher service e.g. LU=ss0007, TP=sapdp00).

A connection from R/2 via SNA directly to the external program requires an XCOM entry (e.g. EXT_IBM). This contains the LU (e.g. LU=MRB2) and the name of the external program (TP=CCPICT2S) that is to be started on the workstation.

A connection through an R/3 system via the SAP gateway to the external program requires a TXCOM entry (e.g. EXT_IBM). This entry specifies the SAP gateway (GWHOST and GWSERV parameters) that is to be started by the external program and the name of the host (LU=iw1006) on which it is to be started and the program name itself (TP=/usr/sap/C11/SYS/exe/run/ccpict2t). If the external program is not going to run on the same host as the SAP gateway, then it is started from the SAP gateway via remote shell (rsh) or rexec. Remember to check the UNIX authorizations (e.g. entries in.rhosts).

Example Sideinfo File

*******************************************************************
* sideinfo IBM-Workstation
* Date: 15.08.95
*******************************************************************
*
*
*******************************************************************
* CUA-Interface
* Destination is R/2-System K50 CICS
* At the sapgui the destination must be entered as K50. The suffixes _1 _2 _3
* will be handeled by the SAP-Gateway automaticly (LU-pooling).
* LU=K5001 is the name of sideinfo-profile of SNA-Server/6000
*******************************************************************
DEST=K50_1
LU=K5001
TP=X1SA

DEST=K50_2
LU=K5002
TP=X1SA

DEST=K50_3
LU=K5003
TP=X1SA


*******************************************************************
* CUA-Interface
* Destination is R/2-System K50 IMS
* At the sapgui the destination must be entered as K50IMS. The suffixes
* _1 _2 _3 will be handeled by the SAP-Gateway automaticly (LU-pooling).
* LU=K50IMS01 is the name of sideinfo-profile of SNA-Server/6000
*******************************************************************
DEST=K50IMS_1
LU=K50IMS01
TP=K50X1SA

DEST=K50IMS_2
LU=K50IMS02
TP=K50X1SA

DEST=K50IMS_3
LU=K50IMS03
TP=K50X1SA


*******************************************************************
* R/3 -> R/2 connection (R/2 on CICS)
*
* The connection is initiated by the R/3 system.
* These entries are the same as for CUA-Interface. Normally they must be
* defined only once and may be used for both purposes.
*******************************************************************
DEST=K50_1
LU=K5001
TP=X1SA

DEST=K50_2
LU=K5002
TP=X1SA

DEST=K50_3
LU=K5003
TP=X1SA


******************************************************************
* R/2 -> R/3 connection (R/2 on CICS)
*
* The connection is initiated by the R/2 system.
* Via SNA a transaction program is started on the AIX-machine.
* This program searches an entry in the sideinfo with destination equal to
* its own program name (GWHSTC11).
* The sideinfo file will be searched in the home directory of the user-id
* configured in the local_tp profile-definition of SNA-Server.
* The program GWHSTC11 then establishes a connection to the R/3-System defined
* by LU= (Hostname of R/3-System) and TP= (servicename of R/3-System) via
* the SAP-Gateway defined by GWHOST= (hostname of SAP-Gateway-System) and
* GWSERV= (servicename of SAP-Gateway).
*******************************************************************
DEST=GWHSTC11
LU=iw1006
TP=sapdp00
GWHOST=iw1006
GWSERV=sapgw00
PROTOCOL=I
CPIC_TRACE=2


******************************************************************
* External program
* Destination is R/2-System K50 CICS
*******************************************************************
DEST=K50
LU=K5001
TP=X1SA
GWHOST=iw1006
GWSERV=sapgw00
PROTOCOL=C
CPIC_TRACE=2


*******************************************************************
* External program
* Destination is R/2-System K50 IMS
*******************************************************************
DEST=K50IMS
LU=K50IMS01
TP=K50X1SA
GWHOST=iw1006
GWSERV=sapgw00
PROTOCOL=C
CPIC_TRACE=2


*******************************************************************
* External program
* Destination is R/3-System C11
*******************************************************************
DEST=C11
LU=iw1006
TP=sapdp00
GWHOST=iw1006
GWSERV=sapgw00
PROTOCOL=I
CPIC_TRACE=2

Example TXCOM Entry:

Dest LU TP Prot Gateway-Host Gateway-Serv

K50 C iw1006 sapgw00
EXT_IBM iw1006 /usr/sap/C11/.. E iw1006 sapgw00

(The full TP path is /usr/sap/C11/SYS/exe/run/ccpict2t)

Example XCOM entry:

Display ATAB table XCOM Table of the symbolic destinations for CPI-C
-------------------------------------------------------------------------------
Symbolic Dest. LU (Logical Unit) TP (Transaktion prog.) Comm.Type
-------------------------------------------------------------------
C11 MRB1 GWHSTC11
EXT_IBM MRB2 CCPICT2S