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About Siebel Server Load Balancing

Load balancing distributes workload across multiple Siebel Servers. Each server runs an instance of the service you want to load balance. Load balancing also provides failover. If one server fails, then requests are automatically routed to the remaining servers.

You can use load balancing when the Siebel Enterprise Server has two or more Siebel Servers that are not clustered. Load balancing is the preferred method for providing high availability for the following server components:

• Application Object Managers (AOMs)
• Siebel Configurator (uses own load balancing method)
• Siebel EAI (whenever possible)

See also Choosing a Load Balancing Method.

Two methods are available for implementing Siebel Server load balancing for AOMs:

• Siebel native load balancing. With Siebel native load balancing, a load balancing module is built into the Siebel Web Server Extension (SWSE). This module provides software-based load balancing for Siebel Servers. You can use Siebel native load balancing instead of third-party HTTP load balancers.

  (On each Siebel Server, Siebel Connection Broker (SCBroker) provides intraserver load balancing. SCBroker distributes connection requests across multiple instances of Application Object Manager processes running on the same server. For details, see About Siebel Connection Broker.)

• Third-party HTTP load balancing. Oracle has validated third-party, hardware-based HTTP load balancers for use in a Siebel deployment.

  Although Siebel applications are designed to work with standard, third-party HTTP applications, customers should perform compatibility testing before using a nonvalidated load balancer.

NOTE:  For help with configuring Siebel software to support load balancing, create a service request (SR) on OracleMetaLink 3. Alternatively, you can phone Global Customer Support directly to create a service request or get a status update on your current SR. Support phone numbers are listed on OracleMetaLink 3. For configuration and troubleshooting information for third-party HTTP load balancers, contact the third-party vendor directly. See also 477835.1 (Doc ID) on OracleMetaLink 3. This document was previously published as Siebel Technical Note 540.

Figure 2 shows an example of third-party HTTP load balancing.

Figure 2. Example of Third-Party HTTP Load Balancing