Communications Server for z/OS V1R8 TCP/IP Implementation Volume 3: High Availability, Scalability, and Performance

In this IBM Redbooks publication we begin with a discussion of Virtual IP Addressing (VIPA), a TCP/IP high-availability approach introduced by the z/OS Communications Server. We then proceed to show how VIPA can be used for high availability—both with and without using a dynamic routing protocol. Then we discuss a number of different workload balancing approaches that can be used with the z/OS Communications Server. In this book we use the terms internal and external application workload balancing to refer to approaches where the decision as to which application instance should received a given connection request is made within the sysplex environment (such as by Sysplex Distributor) or outside of it (using a separate, external, workload balancing solution), respectively. Finally, we explain the optimized Sysplex Distributor intra-sysplex load balancing. This function is an improved multi-tier application support using optimized local connections together with weight values from extended WLM interfaces. For more specific information about CS for z/OS base functions, standard applications, and security, reference the other volumes in the series. These are: Communications Server for z/OS V1R8 TCP/IP Implementation, Volume 1 - Base Functions, Connectivity, and Routing, SG24-7339 Communications Server for z/OS V1R8 TCP/IP Implementation, Volume 2 - Standard Applications, SG24-7340 Communications Server for z/OS V1R8 TCP/IP Implementation, Volume 4 - Policy-Based Network Security, SG24-7342