1. Understanding Solutions

3. An Example of clustering multiple OSB physical instances involves the deployment of multiple servers and the installation of OSB per server with one server being designed as the administration server and the secondary server as a managed server. Based on these physical instances of OSB per physical server that are clustered, logical OSB instances can be deployed on these physical servers, for example, you may 1:4 ratio which means one physical in stance of OSB to four logical instances. These instances can run simultaneously and work together to provide increased scalability and reliability. The server instances that constitute a cluster can run on the same physical server or be located on different physical servers. We can increase a cluster’s capacity by adding additional logical server instances to the cluster on an existing physical server or can add additional physical servers to the cluster to host the incremental server instances
In addition, a router (hardware or software) needs to be deployed if you need inbound HTTP load balance functions. The persistent configuration for a domain of Oracle WebLogic Server instances and clusters is stored in an XML configuration file (config.xml) in the config directory of the root directory of your Oracle Service Bus domain.

4. Physical Topology of deployment of a Clustered OSB environment with views from the data-tier.

6. Server Load Balancing w/Oracle HTTP Server
Oracle HTTP Server is a web server with built-in WebLogic Server Proxy Plug-In module to act as HTTP front-end for one or more WebLogic servers. This built-in receives the incoming request from the client and load balances the request to one or more WebLogic Servers.
Oracle HTTP Server includes the mod_wl_ohs module, which routes requests to Oracle WebLogic Server. The mod_wl_ohs module provides the same load balancing functionality as mod_weblogic, the Oracle WebLogic Server Plug-in for Apache HTTP Server. See "Configuring the mod_wl_ohs Plug-In for Oracle HTTP Server" in Oracle Fusion Middleware Using Web Server 1.1 Plug-Ins with Oracle WebLogic Server for more information. See Section , "Configuring mod_wl_ohs.conf" for more information on the mod_wl_ohs module.

7. Server Load Balancing w/Oracle Traffic Director
Oracle Traffic Director is a highly available Application Delivery Controller with WebLogic inter-operability enhancements to allow incoming requests to be efficiently throttled to one or more WebLogic server clusters. Oracle Traffic Director is a fast, reliable, and scalable layer-7 software load balancer. You can set up Oracle Traffic Director to serve as the reliable entry point for all HTTP, HTTPS and TCP traffic to application servers and web servers in the back end. Oracle Traffic Director distributes the requests that it receives from clients to servers in the back end based on the specified load-balancing method, routes the requests based on specified rules, caches frequently accessed data, prioritizes traffic, and controls the quality of service. You can use Oracle Traffic Director with Exalogic only.