Front cover Practical Migration to Linux on System z Overview and migration methodology Migration analysis Hands-on migration case study Lydia Parziale Joseph Apuzzo Saulo Augusto M Martins da Silva Louis Henderson Manoj Srinivasan Pattabhiraman Richard Sewell ibm.com/redbooks International Technical Support Organization Practical Migration to Linux on System z October 2009 SG24-7727-00 Note: Before using this information and the product it supports, read the information in “Notices” on page xi. First Edition (October 2009) This edition applies to z/VM Version 5.3 and Version 5.4, Novell SUSE Linux Enterprise Server Version 10 and Version 11, and Red Hat Enterprise Linux Version 5.3. © Copyright International Business Machines Corporation 2009. All rights reserved. Note to U.S. Government Users Restricted Rights -- Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Notices . xi Trademarks . xii Preface . xv The team who wrote this book . xv Become a published author . xviii Comments welcome. xviii Part 1. Overview and migration methodology . 1 Chapter 1. Migration considerations . 3 1.1 Reason to migrate systems. 4 1.1.1 How green is your data center . 4 1.1.2 The IBM Big Green server consolidation . 7 1.2 Benefits of migrating to Linux on System z . 7 1.3 Reasons to select Linux on System z . 9 1.3.1 System z strengths . 10 1.3.2 Value of Linux on System z. 12 1.3.3 Choosing workloads to migrate to IBM System z . 13 1.4 z/VM virtualization for Linux on IBM System z . 13 1.4.1 Leveraging the power of z/OS for distributed platforms . 15 1.4.2 What is Linux on System z . 15 1.5 Sizing workloads for migration . 17 1.6 Total Cost of Ownership analysis . 18 Chapter 2. Stakeholder considerations. 23 2.1 Stakeholder definitions . 24 2.1.1 Business stakeholders . 24 2.1.2 Information Technology stakeholders . 25 2.2 Assembling the stakeholders . 28 Chapter 3. Migration methodology . 31 3.1 Migration approach . 32 3.1.1 Identify the stakeholders . 33 3.1.2 Pre-assessment . 34 3.1.3 Define success criteria . 34 3.1.4 Finalize the new environmental stack . 34 3.1.5 Pilot proof of concept . 35 3.1.6 Decision to migrate . 36 © Copyright IBM Corp. 2009. All rights reserved. iii 3.1.7 Resource estimation . 36 3.1.8 Actual migration . 37 3.1.9 Verification testing. 37 3.1.10 Verification of success criteria. 38 Chapter 4. Migration Planning checklist . 39 4.1 The Planning checklist . 40 4.2 Hardware Planning checklist . 40 4.3 Product and Tools checklist . 41 4.3.1 Application Implementation checklist . 42 4.3.2 Training checklist . 44 4.3.3 Application Environment checklist. 45 Part 2. Migration analysis. 47 Chapter 5. z/VM and Linux on System z technical concepts . 49 5.1 Virtualization concepts . 50 5.1.1 z/VM Operating System components . 51 5.1.2 Logical partition . 52 5.1.3 CPU. 52 5.1.4 Memory . 52 5.1.5 Disk . 55 5.1.6 Network . 56 Chapter 6. Network analysis. 57 6.1 Network migration overview . 58 6.1.1 Single network scenario . 58 6.1.2 Multiple network scenario . 62 6.2 Steps for a successful network migration . 69 Chapter 7. Storage analysis . 71 7.1 Data migration . 72 7.1.1 Online data migration . 72 7.1.2 Offline data migration . 73 7.1.3 Steps for a successful offline storage migration . 76 7.2 Linux on System z - preinstallation considerations . 76 7.2.1 Linux file system . 77 7.2.2 Shared file system. 80 7.2.3 ECKD and zFCP devices . 82 7.2.4 Logical Volume Manager devices . 82 Chapter 8. Application analysis . 85 8.1 Why to migrate applications . 86 8.2 Which applications can be migrated . 86 iv Practical Migration to Linux on System z 8.2.1 Financial benefits of a migration . 87 8.3 Selecting an application for migration to Linux on System z . 87 8.3.1 Applications unsuitable for migration to Linux on System z . 88 8.3.2 Applications suitable for migration to Linux on System z . 88 8.4 Applications best suited for migration . 89 8.4.1 IBM software . 89 8.4.2 Oracle . 89 8.4.3 Other software. 90 8.4.4 Selecting an application for a proof of concept . 92 8.4.5 Applications not supported on Linux on System z . 93 8.4.6 Application interdependencies . 93 8.5 Successful application migration . 94 8.5.1 Special considerations for migrating a Java application . 94 8.5.2 Special considerations for migrating C++ applications . 94 8.5.3 Steps for an application migration. 96 Chapter 9. Database analysis. 99 9.1 Prior to database migration . 100 9.1.1 Migrating a single instance . 100 9.1.2 Migrating multiple instances . ..