Front cover Implementing PowerHA for IBM i Embrace PowerHA for i to configure and manage high availability Leverage the best IBM i 6.1 HA enhancements Understand pros and cons of different HA alternatives Sabine Jordan Kent Kingsley Vivian Kirkpatrick Dave Martin Chris Place Roberta Placido Larry Youngren Hernando Bedoya Jim Denton Monti Abrahams Kolby Hoelzle Jose Goncalves Paul Swenson Jana Jamsek Fred Robinson ibm.com/redbooks International Technical Support Organization Implementing PowerHA for IBM i November 2008 SG24-7405-00 Note: Before using this information and the product it supports, read the information in “Notices” on page ix. First Edition (November 2008) This edition applies to IBM i 6.1. © Copyright International Business Machines Corporation 2008. 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 . ix Trademarks . .x Preface . xi The team that wrote this book . xi Become a published author . xvi Comments welcome. xvi Part 1. Introduction and background . 1 Chapter 1. Introduction: PowerHA for i . 3 1.1 IBM i Business Continuity Solutions . 4 1.2 Choosing a solution. 5 1.3 Further considerations . 7 1.4 Clustering . 8 1.5 Summary. 9 Chapter 2. High-availability building blocks . 11 2.1 Building blocks: Clustering for enhanced high availability. 12 2.1.1 Definition of a cluster . 12 2.1.2 What clustering gives you . 13 2.1.3 Cluster components . 13 2.2 Building blocks: Independent auxiliary storage pools . 14 2.3 Building blocks: Journaling and commitment control . 16 2.3.1 Journaling protection in a clustered environment . 16 2.3.2 Commitment control in a clustered environment. 17 2.4 Data resilience . 17 2.4.1 Logical replication . 17 2.4.2 Switched disk . 18 2.4.3 Cross-site mirroring. 18 2.5 Application resilience . 22 2.6 Environment resilience: Administrative domain. 23 2.7 Building blocks: Practice, practice, practice . 26 Chapter 3. Introducing PowerHA for i . 27 3.1 PowerHA for i introduction . 28 3.2 Graphical interfaces . 29 3.2.1 High Availability Solutions Manager GUI (HASM GUI) . 30 3.2.2 Cluster resource service GUI: Task-based approach . 32 3.2.3 PowerHA for i and IBM i commands . 33 Chapter 4. High-availability technologies . 37 4.1 Introduction . 38 4.2 Switched disk solution. 38 4.3 Geographic mirroring solution . 40 4.3.1 Overview . 40 4.3.2 How geographic mirroring works. 41 4.3.3 Requirements for geographic mirroring. 47 4.3.4 Recommendations when using geographic mirroring. 49 © Copyright IBM Corp. 2008. All rights reserved. iii 4.3.5 Combining geographic mirroring and switched disk . 51 4.4 FlashCopy . 51 4.4.1 FlashCopy overview . 52 4.4.2 FlashCopy and PowerHA for i. 55 4.4.3 Planning and requirements . 56 4.4.4 Combining geographic mirroring and FlashCopy . 57 4.5 Metro mirror. 58 4.5.1 Metro mirror overview . 59 4.5.2 Basic metro mirror operation and options . 60 4.5.3 Metro mirror with PowerHA for i . 61 4.5.4 Planning . 62 4.6 Global mirror . 62 4.6.1 Functions used in global mirror. 63 4.6.2 How global mirror works . 64 4.6.3 Global mirror with PowerHA for i. 66 4.6.4 Planning and requirements . 66 Part 2. PowerHA for i setup and user interfaces . 69 Chapter 5. Getting started: PowerHA for i . 71 5.1 PowerHA for i installation requirements . 72 5.2 Current fixes . 72 5.3 Tips on the different GUI interfaces . 72 5.3.1 Connectivity . 73 5.3.2 Use the system name, not the IP address . 73 5.3.3 IBM Systems Director Navigator for i5/OS loops/hangs . 74 5.3.4 Cluster Resource Services GUI . 74 5.3.5 DASD GUI. 74 5.4 Requirements for setting up a cluster . 86 5.5 Cluster administrative domain. 87 5.6 Metro/global mirror or FlashCopy . ..