HP Serviceguard A.11.20- Managing Serviceguard Twentieth Edition, August 2011

Adding and Deleting Relocatable IP Addresses .....................................................................68
Load Sharing ...............................................................................................................69
Monitoring LAN Interfaces and Detecting Failure: Link Level.....................................................69
Local Switching ............................................................................................................70
Switching Back to Primary LAN Interfaces after Local Switching...........................................72
Remote Switching .........................................................................................................73
Address Resolution Messages after Switching on the Same Subnet.......................................73
Monitoring LAN Interfaces and Detecting Failure: IP Level.......................................................73
Reasons To Use IP Monitoring.........................................................................................74
How the IP Monitor Works.............................................................................................74
Failure and Recovery Detection Times..............................................................................75
Constraints and Limitations.............................................................................................76
Reporting Link-Level and IP-Level Failures................................................................................76
Example 1: If Local Switching is Configured......................................................................76
Example 2: If There Is No Local Switching........................................................................77
Automatic Port Aggregation................................................................................................77
VLAN Configurations..........................................................................................................78
What is VLAN?............................................................................................................78
Support for HP-UX VLAN................................................................................................78
Configuration Restrictions...............................................................................................79
Additional Heartbeat Requirements.................................................................................79
Volume Managers for Data Storage..........................................................................................79
Types of Redundant Storage................................................................................................79
About Device File Names (Device Special Files).....................................................................80
Examples of Mirrored Storage.............................................................................................80
Examples of Storage on Disk Arrays.....................................................................................82
Types of Volume Manager..................................................................................................84
HP-UX Logical Volume Manager (LVM)..................................................................................84
Veritas Volume Manager (VxVM).........................................................................................84
Propagation of Disk Groups in VxVM..............................................................................84
Package Startup Time with VxVM....................................................................................84
Veritas Cluster Volume Manager (CVM)................................................................................85
Cluster Startup Time with CVM........................................................................................85
Propagation of Disk Groups with CVM.............................................................................85
Redundant Heartbeat Subnets.........................................................................................86
Comparison of Volume Managers........................................................................................86
Responses to Failures .............................................................................................................88
System Reset When a Node Fails ........................................................................................88
What Happens when a Node Times Out.........................................................................88
Example..................................................................................................................88
Responses to Hardware Failures...........................................................................................89
Responses to Package and Service Failures ...........................................................................90
Responses to Package and Generic Resources Failures............................................................90
Service Restarts .................................................................................................................91
Network Communication Failure .........................................................................................91
4 Planning and Documenting an HA Cluster ..................................................92
General Planning ..................................................................................................................92
Serviceguard Memory Requirements.....................................................................................92
Planning for Expansion ......................................................................................................92
Hardware Planning ................................................................................................................93
SPU Information ................................................................................................................94
Network Information .........................................................................................................94
LAN Information ..........................................................................................................94
Setting SCSI Addresses for the Largest Expected Cluster Size ..................................................95
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