GSE WG z/os 28. März 2014 Help! I Want to Migrate from IMS to DB2! WITHOUT REWRITING APPLICATION PROGRAMS DL/2 technical overview and case studies Enrico Haak InSoft Software GmbH
Agenda What is transparent database migration? Transparent database migration as part of a legacy modernization program DL/2 technology overview Case studies Next steps 2
Why are we using IMS? A reminder Extremely high performance Over 46,000 transaction per second on a single IMS image Unequaled Transaction volumes Large package distribution company: 180 million txns per day in a single image 500 million accounts for one customer 300+ million users served every day Extremely high availability Large bank: 1.75 hours of downtime over 10 years, of which 1.5 was planned Customers have seen 3000+ days no unplanned outages Ideal when runtime costs are more important than ad-hoc usage Typically significantly less CPU and storage consumed than relational technology Takes advantage of specialty engines for Java (Source: IBM Corporation 2013) 3
What do we mean by transparent data migration? No changes to application programs. None. Zero. Nada. Different DB2 design models can be deployed for different IMS databases DB2 design model can be changed at any time to help meet new business needs IMS/DB can be eliminated once all databases are migrated IMS database tools no longer required Fastest route to DB2 and value delivery LOWEST RISK MIGRATION APPROACH PROVEN TIME AND TIME AGAIN 4
Enterprise modernization alternatives Rewrite existing application programs Data propagation or replication Packaged/ERP solution Do nothing 5
Transparent migration is what we do DL/2 IMS/DB to DB2 migration VS/2 VSAM to DB2 migration Financial and Insurance Services State and local governments Manufacturing Retail and Distribution No specific business sector VS/2 is resold by as CICS VSAM Transparency 5697-I76 6
Overview before DL/2 migration Application program IMS stub IMS 7
Overview - during DL/2 migration Application program DL/2 stub Batch utility to locate the IMS stub in your application programs and replace with DL/2 version Data migrated to DB2? NO YES Static SQL IMS DB2 8
Overview - after DL/2 migration Application program DL/2 stub DB2 9
Accessing IMS databases IMS/DC DBCTL CICS/TS DLISAS DBRC B A T C H BMP DLI/DBB 10
DB2 design summary Each IMS segment maps to one DB2 table IMS concatenated key becomes DB2 primary key DB2 referential integrity ensures hierarchic integrity User defined DB2 table names, column names Optionally, DB2 design based on copybook/record definition Data transformation using built in conversion facilities Date fields Numeric fields May require data cleansing Different design models can be deployed by different segments 11
DB2 design options Migration complexity/time / Effort DBD Copy DBD Copy DBD Copy DBD PICX PIC9 CMP3 PIC9 PIC 9 SEQ SCH PICX PIC9 CMP3 PIC9 PIC 9 SEQ SCH PICX PIC9 CMP3 PIC9 PIC 9 SEQ SCH SEQ SCH OPTION 4 OPTION 3 OPTION 2 OPTION 1 key1 key2 col1 CHAR DEC *DEC DEC INT * Custom user exits for field validation or to support mapping to multiple tables key1 key2 col1 key1 key2 col1 col2 col3 col2 col3 CHAR DEC CHAR DEC INT col2 col3 CHAR columns key col col1 col2 col3 CHAR columns Application testing Time / Effort Pref IMS segment data 12 CK DB2 table data
Typical migration project Databases grouped by application/size/complexity for optimal testing Primarily 3 main project phases: Map/migrate Application testing Production cutover Database Group n Eliminate IMS Database Group 2 Database Group 1 Database Group 3 Database mapping usually performed by InSoft/Circle TIME 13
Why the transparency approach? NO application program changes are required LOWEST RISK migration strategy bite-sized chunks REDUCED COSTS through elimination of IMS DB and IMS tools licenses SIMPLIFICATION of DBA support through DBMS convergence CHOICE of migration methods to meet differing requirements Simple, rapid method to reduce costs very quickly More measured method to meet DB2 design objectives A combination of both Simple method first, measured method later MINOR JCL changes (which can be made in advance) 14
Migrate to eliminate costs Health Insurance Migration of two business critical applications (209 IMS databases) Project complete within 8 months using option 2, following a POC Limited IMS support staff Significant on-going annual savings Eliminated IMS DB license and tools license costs Building Supplies Manufacturing and Distribution Migration of complex suite of IMS applications accessing 85 Databases Limited in-house application knowledge and support Elimination of IMS DB license and tools license costs Single production cutover in IMS elimination mode Option 3 design 15
Migrate to DB2 for business need State Government Dept of Motor Vehicles Migration to support modernization of Title and Registration system Maintained original IMS system but allowed enhancement and modernization new system without the risk and cost 2 failed multi million dollar attempts at an application re-write West Coast State Government Dept of Corrections Requirement to improve data management and data sharing across multiple State agencies Deploy next generation application while supporting co-existence with existing application over a number of years Extra benefit IMS DB elimination once other agencies had ceased IMS use One failed multi-million application rewrite 16
Combination of business need and cost reduction Retail distribution Migration of 4 core application databases option 3 design Additional 82 databases converted option 1 design Core application migration to DB2 design to support on-going development Initial study for re-write 68 man years! Business need to move to RDBMS and cost elimination East Coast State Government Department of Corrections Major business requirement to eliminate very high cost of IMS licensing Option 3 design required significant data cleansing effort for 1200 numeric fields (including interesting dates...) Large databases (> 25 Gb) 17
Circle/InSoft services Free of charge DBD and PSB review service Proof of concept Mapping and migration service Onsite support for production cutover 24 x 7 x 365 defect support 18
Next steps Individual Technical Overview session via conference call Discuss how DL/2 would work in your own unique environment PSB and DBD Review service Determine the scope of a migration project and provide budgetary estimates Opportunity to talk with a DL/2 reference Talk with clients who have been through an entire migration and hear first hand why they chose DL/2 and Circle Enrico Haak: +49 (211) 4403166 eh@insoft-software.de 19
InSoft Software GmbH Home-Grown Products VTAS TDLI TVSM DB/IQ Virtual Table Processing System general table processing for all applications. End-user maintenance z/vse and z/os, CICS DL/I (IMS) Editor & Call Generator DL/I Editor for application programmers and DBAs z/vse and z/os, CICS, IMS/DB, DL/I VSAM Editor & I/O Monitor VSAM Editor for application programmers and DBAs z/vse and z/os, CICS DB2 Utilities - QA, IA+, WL+, QA+, PM powerful DB2 utilities for application programmers and DBAs z/os, DB2 V. 8.1, 9, 10, 11 Supports Eclipse based IDEs