Managing Serviceguard Sixteenth Edition, March 2009

Volume Managers for Data Storage..................................................................................107
Types of Redundant Storage.......................................................................................107
About Device File Names (Device Special Files).........................................................107
Examples of Mirrored Storage.....................................................................................108
Examples of Storage on Disk Arrays...........................................................................111
Types of Volume Manager...........................................................................................113
HP-UX Logical Volume Manager (LVM)....................................................................113
Veritas Volume Manager (VxVM)...............................................................................113
Propagation of Disk Groups in VxVM...................................................................114
Package Startup Time with VxVM.........................................................................114
Veritas Cluster Volume Manager (CVM)....................................................................114
Cluster Startup Time with CVM............................................................................115
Propagation of Disk Groups with CVM................................................................115
Redundant Heartbeat Subnets...............................................................................115
Comparison of Volume Managers...............................................................................116
Responses to Failures .......................................................................................................118
System Reset When a Node Fails ...............................................................................118
What Happens when a Node Times Out...............................................................118
Example............................................................................................................118
Responses to Hardware Failures.................................................................................119
Responses to Package and Service Failures ................................................................120
Service Restarts ...........................................................................................................121
Network Communication Failure ..............................................................................121
4 Planning and Documenting an HA Cluster ...............................................................................123
General Planning .............................................................................................................123
Serviceguard Memory Requirements..........................................................................124
Planning for Expansion ..............................................................................................124
Hardware Planning ..........................................................................................................124
SPU Information .........................................................................................................125
Network Information ..................................................................................................126
LAN Information ...................................................................................................126
Setting SCSI Addresses for the Largest Expected Cluster Size ..................................127
Disk I/O Information ..................................................................................................128
Hardware Configuration Worksheet ..........................................................................129
Power Supply Planning ...................................................................................................130
Power Supply Configuration Worksheet ...................................................................131
Cluster Lock Planning......................................................................................................131
Cluster Lock Disk and Re-formation Time .................................................................132
Planning for Expansion...............................................................................................132
Using a Quorum Server...............................................................................................132
Quorum Server Worksheet ....................................................................................133
LVM Planning ..................................................................................................................133
6 Table of Contents