Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved


Chapter 1 Installing Service Gateway for IMS/DB : Preparing the IMS Environment

Preparing the IMS Environment
Before running Service Gateway for IMS/DB, prepare the following items for the IMS environment:
If using Cross Memory Services for the Gateway to communicate with the Data Object Broker, authorize specific data sets.
You must also consider the level of security required for your environment and whether TIBCO Object Service Broker, IMS, and DB2 data must be updated in a single transaction. Refer to Implementing Security and Implementing Fail Safe Processing for more information.
Defining Gateway Program Specification Blocks
Each class of the Gateway requires a PSB that defines all the IMS databases that you want to access from TIBCO Object Service Broker through that class of Gateway, and the processing options available for each database. You must define a database Program Control Block (PCB) for each database you need the Gateway to access. The PSB defined for the BMP, CICS DL/I and DRA interface is locked for the time of the TIBCO Object Service Broker transaction. The CICS interface can use different PSBs but only one per TIBCO Object Service Broker transaction.
If a database contains non-unique segments (no key or multiple sequence keys), define at least two identical PCBs. The first PCB is reserved for unique segment access. Subsequent PCBs are used to maintain the position in the database when accessing non-unique segment occurrences. The number of PCBs required is the maximum number of non-unique IMS tables that map to the same database, accessed in a single TIBCO Object Service Broker transaction.
Gateway PSB Requirements:
The Gateway uses PATH calls, therefore, include the P processing option in the PROCOPT (Processing Option) parameter for each database PCB (for example, AP or IRDP). If you specify the PROCOPT (Processing Option) parameter on a SENSEG statement, include the P option, otherwise the SENSEG specification overrides the PCB specification. This could result in a DL/I AM status code failure.
You must include the CMPAT=YES option on the PSBGEN statement because the Gateway expects the first PCB to be an I/O PCB.
The following is a sample PSB definition:

 
 * Sample PSB definition suitable for TIBCO Object Service Broker
*
CUSTOMER PCB TYPE=DB,DBDNAME=CUSTDB,PROCOPT=AP,KEYLEN=28
SENSEG NAME=CUSTROOT,PARENT=0
SENSEG NAME=CUSTDEF1,PARENT=CUSTROOT
SENSEG NAME=ADDRESS,PARENT=CUSTROOT,PROCOPT=IRDP
*
* The TIBCO Object Service Broker FSLEVEL=1 database
* See: <HLQNONV>.<INSTVER>.CNTL(XIMSTRXP)
*
HRNTRXDB PCB TYPE=DB,NAME=HRNTRXDB,PROCOPT=AP,KEYLEN=16
SENSEG NAME=HRNTRXDB,PARENT=0
*
PSBGEN PSBNAME=CUSTPSB,LANG=ASSEM,CMPAT=YES
END

 
Defining IMS Secondary Index Access
If you always access an IMS database through a secondary index, include the PROCSEQ parameter with all PCBs defined for that database. If you access an IMS database using both primary and secondary processing sequences, complete the following steps:
1.
If the physical database has no logical relationships, the sequence of segments is exactly the same as the physical database definition.
2.
The sequence of segments should reflect the order in which segments are returned when using secondary index processing. However, if the INDICES parameter is defined (instead of PROCSEQ), the sequence of the segments stays the same as the logical database definition.
3.
For example, to retrieve data using the primary processing sequence, create an IMS table definition using the physical database definition.
To retrieve data using the secondary processing sequence (using a secondary index), create an IMS table definition using the logical database and specify the secondary index fields (Idx=Y) as parameters or an access value for the table.
Authorizing Data Sets For Cross Memory Services
If an instance of the Gateway uses Cross Memory Services to communicate with the Data Object Broker, ensure that all data sets in the STEPLIB concatenation list are APF authorized.
Defining the Gateway to the IMS Online System
To run the Gateway using the BMP interface to IMS DB/TM or DBCTL, define the IMS APPLCTN macro as shown:
APPLCTN PGMTYPE=BATCH,PSB=HRNIMSS,SCHDTYP=PARALLEL
Rollback Considerations For the DL/I Interface
The Gateway uses the DL/I ROLB call to roll back any updates if they are required or requested. In order for the ROLB call to be successful, if using the DL/I interface, you must set the dynamic backout parameter to Yes (BKO=Y). An IEFRDER data set is also required for IMS logging. Ensure that this data set remains on DASD and is large enough to accommodate rollback processing. Refer to Starting the Gateway for more information.

Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved