This chapter introduces you to the application programming interface (API) for Group Services that is provided by the IBM Parallel System Support Programs for AIX (PSSP) and by the Enhanced Scalability feature of the IBM High Availability Cluster Multi-Processing for AIX Licensed Program (HACMP/ES).
The chapter begins by explaining why high availability is important in a multicomputer environment and how Group Services can help you achieve it. It continues with an introduction to Group Services functions and how you can use them, followed by an explanation of the concepts and operation of the Group Services subsystem. This chapter also helps you make design choices as you plan your application's use of the Group Services Application Programming Interface (GSAPI).
For the definitions of terms and concepts that are introduced in this chapter, see the Glossary.
For information about managing the Group Services subsystem, see PSSP: Administration Guide, SA22-7348.