Front cover IBM PowerHA SystemMirror V7.2 for IBM AIX Updates Dino Quintero Sergio Baeta Shawn Bodily Bernhard Buehler Primitivo Cervantes Bing He Mihai Huica Howard Knight Redbooks International Technical Support Organization IBM PowerHA SystemMirror V7.2 for IBM AIX Updates July 2016 SG24-8278-00 Note: Before using this information and the product it supports, read the information in “Notices” on page ix. First Edition (July 2016) This edition applies to IBM AIX V7100-03-05-1524, IBM PowerHA SystemMirror V7.2.0, IBM AIX V7.1.3.4, IBM AIX V7.2.0, IBM AIX V7.1 TL3 SP5, IBM PowerHA SystemMirror V7.1.1 SP1, IBM PowerHA SystemMirror V7.1.2 SP1, IBM PowerHA SystemMirror V7.1.3 GA, IBM HTTP Server V7.0.0.0. © Copyright International Business Machines Corporation 2016. 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 IBM Redbooks promotions . xi Preface . xiii Authors. xiii Now you can become a published author, too . .xv Comments welcome. .xv Stay connected to IBM Redbooks . .xv Chapter 1. Introduction to IBM PowerHA SystemMirror for IBM AIX . 1 1.1 What IBM PowerHA SystemMirror for IBM AIX is. 2 1.1.1 High availability . 2 1.1.2 Cluster multiprocessing. 2 1.2 Availability solutions: An overview . 3 1.2.1 Downtime . 4 1.2.2 Single point of failure (SPOF) . 5 1.3 History and evolution. 6 1.3.1 PowerHA SystemMirror version 7.1.1. 6 1.3.2 PowerHA SystemMirror version 7.1.2. 7 1.3.3 PowerHA SystemMirror version 7.1.3. 8 1.3.4 PowerHA SystemMirror version 7.2.0. 9 1.4 High availability terminology and concepts . 9 1.4.1 Terminology . 9 1.5 Fault tolerance versus high availability . 11 1.5.1 Fault-tolerant systems. 11 1.5.2 High availability systems. 11 1.6 Additional PowerHA resources . 12 Chapter 2. IBM PowerHA SystemMirror V7.2 for IBM AIX new features . 17 2.1 Resiliency enhancements . 18 2.1.1 Integrated support for AIX Live Kernel Update . 18 2.1.2 Automatic repository replacement. 20 2.1.3 Verification enhancements . 20 2.1.4 Use of Logical Volume Manager rootvg failure monitoring . 21 2.1.5 Live Partition Mobility automation . 23 2.2 Cluster Aware AIX (CAA) Enhancements . 25 2.2.1 Network Failure Detection Tunable. 25 2.2.2 Built in NETMON logic . 25 2.2.3 Traffic stimulation for better interface failure detection . 25 2.3 Enhanced “split brain” handling. 26 2.4 Resource optimized high availability (ROHA) fallovers using Enterprise Pools . 26 2.5 Non-disruptive upgrades . 27 2.6 GLVM wizard. 27 Chapter 3. Planning considerations . 29 3.1 Introduction . 30 3.1.1 Mirrored architecture. 30 © Copyright IBM Corp. 2016. All rights reserved. iii 3.1.2 Single storage architecture . 30 3.1.3 Stretched cluster . 31 3.1.4 Linked cluster . 32 3.2 Cluster Aware AIX repository disk. 33 3.2.1 Preparing for a CAA repository disk . 34 3.2.2 CAA with multiple storage devices . 34 3.3 Important considerations for Virtual Input/Output Server . 39 3.3.1 Using poll_uplink. 39 3.3.2 Advantages for PowerHA when poll_uplink is used . 41 3.4 Network considerations. 42 3.4.1 Dual adapter networks . 42 3.4.2 Single adapter network . 42 3.5 Network File System tie breaker . 42 3.5.1 Introduction and concepts. 42 3.5.2 Test environment setup . 44 3.5.3 NFS server and client configuration . 46 3.5.4 NFS tie breaker configuration . 48 3.5.5 NFS tie breaker tests . 53 3.5.6 Log entries for monitoring and debugging . 58 Chapter 4. What’s new with IBM Cluster Aware AIX and Reliable Scalable Clustering Technology . 63 4.1 CAA. 64 4.1.1 CAA tunables . 64 4.1.2 What is new in CAA overview . 64 4.1.3 Monitoring /var usage . 65 4.1.4 New lscluster option -g . 67 4.1.5 Interface failure detection . 76 4.2 Automatic repository update for the repository disk . 77 4.2.1 Introduction to the automatic repository update . 77 4.2.2 Requirements for Automatic Repository Update. 78 4.2.3 Configuring Automatic Repository Update . ..