Considering Migrating Your IMS to a New Version?

 

By

Ron Steele, LB Software Consultants, September 2004

 

Why migrate?

 

You may want to take advantage of some of the enhancements in V9, which will be covered below.

 

IMS Version 7 support from IBM is planned to end on November 8, 2005. If you are currently running Version 7, you could skip Version 8 and migrate to Version 9. This could save one migration, and it is not required to go to Version 8 before Version 9.

 

IMS Version 6 support ended September 30, 2003.

 

IMS Version 5 support ended September 30, 2001.

 

What’s in Version 9?

 

HALDB Online Reorganization (OLR)

 Reorganization of a database stored using the HALDB (High Availability Large Data Base) feature of IMS can be by partition of the data with concurrent online update and availability. No outage is needed for reorganizations. Applications can access all of the data during reorganizations without restrictions. This allows for totally non-disruptive reorganizations. The pace of the data access can be controlled to minimize impact on I/O to the data and other resources during reorganization. Partitions can be reorganized in parallel and the coordination can be provided through DBRC. OLR supports Data Sharing so that other IMS subsystems may read and update the data in the partitions while they are being reorganized. Reorganizations may be done in any Data Sharing IMS subsystem; this adds flexibility.

 

IVP Enhancements

 

New samples have been added to the IVP (Installation Verification Program) for CQS (Common Queue Server) and the new command environment. IVP variables are imported from previous releases of IMS. The Syntax Checker, which was added in V8, has additional capabilities such as providing support for the definition and maintenance of additional IMS Proclib members.

 

RESLIB Sharing

 

IMS RESLIB contains the IMS Nucleus, some exits, and is built by sysgen and SMP/E (System Maintenance Program/Extended). During System Definition, the Transaction Manager (TM), DB/DC, Data Base Control (DBCTL), and Fast Path (FP) may use the same RESLIB (SDFSRESL).

 

Security Enhancements for RACF

 

These enhancements enable migration from IMS SMU (Security Maintenance Utility) to RACF (Resource Access Control Facility) and implementing all security under RACF. IMS V9 is the last release that will support SMU. The enhancements in V9 may apply to a security product equivalent to RACF.

 

IMS JAVA Remote Database Services

 

IMS databases can be accessed from an EJB (Enterprise Java Bean) on a Distributed J2EE (Java 2 Enterprise Edition) server without additional z/OS application programming. IMS databases can be accessed from workstations using WebSphere and IMS ODBA (Open Data Base Access).

 

XML DB

 

XML (Extensible Markup Language) documents can be stored in IMS databases. XML documents can be composed from non-XML data in IMS databases, and XML documents can be stored as segments and fields. Existing IMS applications written in COBOL, PL/I, etc. can access the XML data.

 

DBRC API

 

An Assembler macro interface is provided that enables vendor and customer-written tools to use DBRC services and to help reduce migration impact in using these tools.

 

Enhanced Command Environment

 

The Common Service Layer (CSL) was introduced in IMS V8 that included the new Operations Manager (OM), Resource Manager (RM), and Structured Call Interface (SCI). The Single Point Of Control (SPOC), a TSO based application was also added. In V9, the Common Service Layer can now use the SPOC and the Operations Manager without the Resource Manager addresspace being present.

 

Sysplex Wide Database Commands

 

This enhancement expands the SPOC to handle database commands. This helps provide a single-system image in the IMSplex. IMSplex QUERY and UPDATE commands for databases and areas can be executed. This would be equivalent to commands such as /DIS, /START, /DBR, /DBD, etc. for databases and areas.

 

Fast Path Enhancements

 

There are new options for opening and closing areas. They can be opened and closed in parallel. Multiple TCBs (Task Control Blocks) are used to accomplish this. Emergency Restart will open all areas that were open when IMS failed.

 

The FP Shared Virtual Storage Option (SVSO) Multi-area Structure Support provides for housing multiple DEDB areas in a single Coupling Facility (CF) structure. Instead of having one CF structure per area, multiple areas can reside in a single CF structure. This reduces the total number of CF structures that need to be defined in a system.

 

Other Enhancements

 

IMS V9 has other enhancements that can be seen in the Announcement Letter 203-216; here is a link to it: http://www-306.ibm.com/fcgi-bin/common/ssi/ssialias?infotype=an&subtype=ca&appname=Demonstration&htmlfid=897/ENUS203-216

 

IMS V9 planned general availability (GA) is October 2004 if the early customer testing goes as desired.

 

Some other information available as of September 2004 is:

·        IMS V9 Release Planning Guide, GC17-7831; here is a link in Acrobat format: http://publibfi.boulder.ibm.com/epubs/pdf/dfsrpgg1.pdf

      Here is a link in BookManager format:

http://publibfi.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/dfsrpgg1/CCONTENTS

·        IMS V9 Fact Sheet, GC18-7697; here is a link:

     http://www-306.ibm.com/software/data/ims/v9/v9fact.pdf

 

Note:

This article went to press prior to the IBM IMS Technical Conference. If any additions, or revisions are required as a result of information presented at that conference, an updated version of this article will be completed. Newsletter subscribers of record will be notified via email of any such revision.   

 

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