In Oracle Solaris, Integrated Load Balancer (ILB) provides Layer 3 and Layer 4 load-balancing capabilities. ILB operates at the network (IP) and transport (TCP/UDP) layers for the Oracle Solaris operating system installed on SPARC-based and x86-based systems. ILB can be used to improve reliability and scalability, and to minimize the response time of network services.
ILB intercepts incoming requests from clients, decides which back-end server should handle the requests based on load-balancing rules, and then forwards the requests to the selected server. ILB can also be used as a router for the back-end server. ILB performs optional health checks and provides the data for the load-balancing algorithms to verify whether the selected server can handle the incoming requests.