User Guide

Contents vii
Defining the Scheduler Refresh Interval.....................................................................................126
Logging Scheduled Events ...........................................................................................................127
Chapter 6: Creating Scalable and Highly Available Web Sites .................129
What is Scalability? .......................................................................................................................130
Performance ..........................................................................................................................130
Load management ................................................................................................................132
Issues Affecting Successful Scalability Implementations..........................................................132
Designing and coding scalable applications.......................................................................133
Avoiding common bottlenecks ............................................................................................137
DNS effects on Web site performance and availability......................................................138
Load testing your Web applications ....................................................................................142
What is Web Site Availability? ......................................................................................................144
Availability & reliability.........................................................................................................145
Common failures...................................................................................................................146
A Web site availability scenario............................................................................................146
Failover considerations.........................................................................................................147
Techniques for Creating Scalable & Highly Available Sites.......................................................149
What is clustering?.................................................................................................................149
Hardware-based clustering solutions..................................................................................150
Software-based clustering solutions....................................................................................152
Combining hardware and software clustering solutions...................................................154
Introducing ClusterCATS for ColdFusion...................................................................................155
ClusterCATS for ColdFusion Features.................................................................................155
ClusterCATS for ColdFusion Components.................................................................................158
ClusterCATS Server ...............................................................................................................158
ClusterCATS Explorer ...........................................................................................................159
ClusterCATS Server Administrator ......................................................................................160
Before You Install..........................................................................................................................161
Review the release notes.......................................................................................................161
Verify system requirements..................................................................................................161
Configure your primary DNS server ....................................................................................163
Configure your Web server’s network settings ...................................................................171
Configure ClusterCATS for use across firewalls..................................................................184
Installing ClusterCATS .................................................................................................................185
Creating Clusters...........................................................................................................................192
Creating clusters with the Cluster Setup Wizard................................................................192
Creating clusters manually...................................................................................................199
Configuring Load Balancing & High Availability Features........................................................203
Configuring server load thresholds......................................................................................203
Configuring session-aware load balancing.........................................................................207
Configuring ColdFusion probes...........................................................................................208
Integrating ClusterCATS with load balancing devices.......................................................211
Configuring administrator alarm notifications ..................................................................215
Configuring administration e-mail support .......................................................................217
Configuring cluster administration security.......................................................................218
Performing Common Cluster Administration Tasks .................................................................223
Changing a server’s state ......................................................................................................224