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Planning the Siebel Application Interface Topology

Before you install the Siebel Application Interface for your Siebel deployment, as described in Installing Siebel CRM Server Modules you must decide how you will distribute instances of Siebel Application Interface and other Siebel CRM modules. For the best performance and scalability, put the Siebel Application Interface on one or more dedicated computers.

This topic is part of Requirements for Installing and Configuring the Siebel Application Interface.

Two basic methods are as follows:

• Single-node. Installing Siebel Enterprise Server modules and Siebel Application Interface on a single compute, node, or operating system instance. (If you do this, then you must use separate installation directories.)
• Distributed. Distributing the preceding modules, where instances of Siebel Application Interface on one or more dedicated computers connect to multiple Siebel Servers in the Siebel Enterprise. These Siebel Application Interface instances can be dynamically balanced for Application Object Manager components on different Siebel Server computers.

  NOTE:  As of Siebel CRM version 17.5, application containers for Siebel Application Interface instances on multiple nodes can be load balanced using Apache HTTP Server (httpd) and Apache Tomcat Connector (mod_jk). For more information about these modules, refer to vendor documentation. If you configure load balancing for application containers in this way, then, whenever an application container fails for a Siebel Application Interface node, the active sessions handled by that node transparently failover to another available healthy application container node.

Each deployment choice involves a trade-off. However, in enterprise-sized deployments, it is strongly recommended that you use a distributed node deployment for the following reasons:

• Less resource contention. Distributing the Siebel Application Interfaces and the Siebel Servers (with Application Object Manager components) on different computers eliminates contention for CPU and other server resources. However, to take advantage of the performance improvement, you must have a high-speed network connection between the two computers.
• Higher fault tolerance. Operating multiple instances of components on multiple computers reduces downtime and the effect of failure on any one computer.
• Greater flexibility with firewalls. Putting Siebel Application Interface on a different computer from the Siebel Server with Application Object Managers lets you deploy your Siebel Application Interface in the DMZ while keeping the Siebel Enterprise Server behind a secure firewall.
• High availability. A multinode configuration is required for deployments that support large numbers of concurrent users or where high availability is an operating requirement.

For more information about Siebel Application Interface, see About the Siebel Application Interface. See also Siebel Deployment Planning Guide and Siebel Security Guide.