IBML VSE to OS/390 Migration Workbook Cliff Bays ** Dave Greenough ** John Hutchinson Dan Janda ** Kevin Jones ** Gilbert Saint-flour International Technical Support Organization http://www.redbooks.ibm.com This book was printed at 240 dpi (dots per inch). The final production redbook with the RED cover will be printed at 1200 dpi and will provide superior graphics resolution. Please see “How to Get ITSO Redbooks” at the back of this book for ordering instructions. SG24-2043-00 IBML International Technical Support Organization SG24-2043-00 VSE to OS/390 Migration Workbook October 1998 Take Note! Before using this information and the product it supports, be sure to read the general information in Appendix D, “Special Notices” on page 553. First Edition (October 1998) This edition applies to Version 2 Release 3 of IBM Virtual Storage Extended/Enterprise Systems Architecture (VSE/ESA), Program Number 5690-VSE, and to all subsequent releases and modifications until otherwise indicated in new editions. It also applies to Version 2 Release 4 of OS/390 (5647-A01) and to all subsequent releases and modifications until otherwise indicated in new editions. Comments may be addressed to: IBM Corporation, International Technical Support Organization Dept. HYJ Mail Station P099 522 South Road Poughkeepsie, New York 12601-5400 When you send information to IBM, you grant IBM a non-exclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you. Copyright International Business Machines Corporation 1998. All rights reserved. Note to U.S. Government Users — Documentation related to restricted rights — Use, duplication or disclosure is subject to restrictions set forth in GSA ADP Schedule Contract with IBM Corp. Contents Figures . xvii Tables . xix Preface . xxi The Team That Wrote This Redbook ........................ xxi Redbook Builders and Key Contributors .................... xxi Authors and Significant Contributors ...................... xxii Comments Welcome . xxii Part 1. Planning the Migration - An Introduction ......................... 1 Chapter 1. Why Customers Migrate ......................... 3 1.1 A Synopsis of This Book ............................. 3 1.2 Traditional Reasons for Migrating ........................ 4 1.2.1 Business Consolidation . 4 1.2.2 Mergers/Acquisitions . 5 1.2.3 Capacity Constraints . 5 1.2.4 Image . 9 1.3 Functional Reasons for Migrating to OS/390 .................. 10 1.3.1 Applications Availability . 10 1.3.2 Systems Management . 10 1.3.3 Connectivity . 11 1.3.4 Systems Availability . 11 1.3.5 Staff Availability . 12 Chapter 2. Sizing the Effort .............................. 13 2.1 Introduction to Sizing ............................... 13 2.1.1 Defining the Migration Project Objectives ................. 13 2.1.2 Areas of VSE and OS/390 Differences ................... 14 2.1.3 Comparison of Basic VSE Functions & Components to OS/390 .... 16 2.2 OS/390 Components/Products/Subsystems . 18 2.2.1 The OS/390 Operating Environment .................... 19 2.2.2 Subsystem Level Comparison/Affinity ................... 24 2.3 What Changes Between VSE and OS/390? ................... 24 2.3.1 Philosophical Changes . 24 2.4 Who is Affected by This Migration? ....................... 26 2.4.1 Job Roles and Normal Activities ...................... 26 2.5 Approaches to Migration ............................. 27 2.5.1 Disclaimer . 27 2.5.2 OS/390 Conversion and Production Implementation Strategies .... 27 2.5.3 VM/ESA Guest Support in Your VSE to OS/390 Migration ....... 29 2.5.4 Staffing Strategies . 29 2.5.5 Conversion Tools . 30 2.6 Educational Requirements . 31 2.6.1 Introduction . 31 2.7 Scope of Work and Challenges .......................... 32 2.7.1 Application Inventory . 32 2.7.2 Program Conversion . 33 2.7.3 JCL Conversion . 33 2.7.4 File Migration . 35 Copyright IBM Corp. 1998 iii 2.7.5 Project Management . 37 2.7.6 Automated Operations . 37 2.8 Cost Considerations . 38 2.9 OS/390 Documentation Resources ....................... 39 2.9.1 Introduction References . 39 2.9.2 Key Documents and Other References .................. 40 2.9.3 Web URL . 40 Chapter 3. Developing the Plan ............................ 41 3.1 Overview . 41 3.1.1 References . 41 3.1.2 Recommendations . 41 3.2 Plan Components . 45 3.2.1 Approach . 45 3.2.2 Team . 45 3.2.3 Tasks . 47 3.2.4 Milestone Events . 48 3.2.5 Education . 49 3.3 Progressive versus Mass Conversion ...................... 49 3.3.1 Approach Differences . 49 3.3.2 Historical Perspective . 50 3.3.3 Shared Application Files and Databases ................. 50 3.3.4 Shared Application Code .......................... 50 3.3.5 Operations Support Staffing ......................... 50 3.3.6 Automated Operations Tools ........................ 50 3.3.7 Standardized Conversion Deliverables and Automation ........ 51 3.3.8 Risk Management . 51 3.3.9 Complexity of Implementation ....................... 51 3.4 Plan Examples . 53 3.4.1 Project Schedule . 54 3.4.2 Project Plan Example ............................. 56 Part 2. Converting the VSE Operating System to the OS/390 Operating System .. 67 Chapter 4. Job Control Language (JCL) Differences and Considerations ... 69 4.1 The Philosophy of JCL in System/390 ...................... 69 4.1.1 VSE/ESA′s Job Control Language Philosophy .............. 70 4.1.2 OS/390′s Job Control Philosophy ...................... 70 4.2 High Level Similarities ............................... 72 4.2.1 JCL Statement and Job Layout ....................... 72 4.2.2 Spooling . 73 4.3 JCL Differences Between VSE and MVS .................... 73 4.3.1 Job Input . 73 4.3.2 JCL Expansion . 76 4.3.3 Operator Flexibility and Intervention .................... 76 4.3.4 Allocation of Resources ........................... 78 4.3.5 Hidden JCL . 78 4.3.6 Device Address Specifications ....................... 80 4.3.7 Catalogs . 81 4.3.8 Partition Dependent Codes in JCL ..................... 81 4.3.9 Communication Region - DATE and UPSI ................. 81 4.3.10 VSE Job Control Statements ........................ 82 4.3.11 MVS Job Control Statements ....................... 84 4.3.12 Comparison of VSE and MVS JCL - A Summary ............ 86 iv VSE to OS/390 Migration Workbook 4.3.13 Summary of MVS JCL Statements .................... 88 4.4 JECL . 89 4.4.2 Comparison of POWER and JES2 JECL - A Summary ......... 89 4.4.3 Summary of JES2 JECL - A Table ..................... 90 4.5 VSE and MVS JCL Comparison Example .................... 91 4.5.1 Sample VSE JCL ................................ 92 4.5.2 Sample MVS JCL ............................... 93 4.5.3 Sample VSE plus Carry-Over ........................ 94 Chapter 5. Disk and Tape Storage Considerations ................ 97 5.1 Access Method Similarities and Differences .................. 97 5.1.1 Access Methods . 97 5.1.2 Operating System Implementations .................... 98 5.1.3 Miscellaneous Functions . 99 5.2 Data Set Naming Considerations ........................ 99 5.2.1 VSE Considerations . 99 5.2.2 OS/390 Considerations . 99 5.3 Storage and Space Management ....................... 100 5.3.1 VSE Considerations . 100 5.3.2 OS/390 Considerations . 100 5.3.3 System Managed Storage ......................... 100 5.3.4 Implementing DFSMS . 102 5.4 Tape Similarities and Differences ....................... 103 5.4.1 Volume Interchangeability . 103 5.4.2 Standard Labels . 103 5.4.3 No Labels . 105 5.4.4 Nonstandard Labels . 106 5.4.5 Bypass Label Processing Facility in OS/390 .............. 106 5.5 DASD Similarities and Differences ...................... 108 5.5.1 Volume Interchangeability . 108 5.5.2 DASD (VTOC) Processing ......................... 108 5.5.3 Indexed VTOC Considerations (OS/390) ................. 109 5.6 VSAM Differences . 110 5.6.1 Introduction . 110 5.6.2 OS/390 Catalogs . 110 5.6.3 OS/390 Catalog Management ....................... 114 5.6.4 OS/390 - VSE/VSAM Catalog Compatibility ............... 117 5.6.5 VSAM Functional Differences ....................... 119 5.6.6 Data Sharing and Integrity ......................... 125 5.6.7 Programming Languages and VSAM Support ............. 131 5.6.8 VSAM Error and Reason Code Compatibility .............. 131 5.6.9 DFSORT and VSAM Considerations ................... 131 Chapter 6. CICS . 133 6.1 Introduction . 133 6.1.1 Overview CICS Transaction Server ................... 133 6.1.2 Essential Supplemental Reading and Migration Support Material . 134 6.1.3 General Compatibility Comments .................... 135 6.1.4 Virtual Storage Considerations for MVS ................. 135 6.1.5 CICS General System Considerations .................. 136 6.1.6 CICS Macro Resource Definition Table Changes ........... 140 6.1.7 CSD and RDO Considerations ...................... 143 6.1.8 CICS System Data Sets Requirements ................. 145 6.1.9 CICS System Program Interface and Exits ............... 147 6.1.10 CICS Transaction Security ........................ 149 Contents v 6.1.11 CICS UPSI . 149 6.1.12 Application Programming . 150 6.1.13 CICS/VSE and TS Coexistence Considerations ............ 153 6.1.14 Testing and Problem Determination Considerations ......... 153 6.1.15 Vendor Applications . 154 6.2 CICS with DL/I ................................... 154 Chapter 7. ICCF and TSO .............................. 155 7.1 Preparing to Use the System .......................... 155 7.1.1 User Profiles . 155 7.1.2 LOGON Procedures . 157 7.1.3 Message Facilities . 157 7.1.4 Security . 157 7.1.5 Summary ................................... 158 7.2 Using the System ................................. 158 7.2.1 Accessing the System ........................... 159 7.2.2 Entering and Manipulating Data ..................... 159 7.3 Executing Programs at a Terminal ...................... 161 7.4 Submitting Jobs for Batch.