2.2.2 How many Parallel Sysplexes do I need? The number of Parallel Sysplexes needed in an installation will vary. For most installations, however, two Parallel Sysplexes is likely to be the norm, with maybe a third monoplex systems programming sandpit. This should cover both the current users' production environments and systems programmers' testing environments. For some installations, a need will exist for additional Parallel Sysplexes because of availability, technical, or business reasons. Application development will normally be part of the production sysplex. As in the past, when new releases of software are brought in, these new releases will be put on the development images first. For companies offering Facilities Management (outsourcing providers) services, for example, there might be specific business reasons why they would not want to include all their workloads in the same Parallel Sysplex. Some of the specific things to consider when deciding how many Parallel Sysplexes to have are: Ease of operation and management It is easier to operate and manage a single large Parallel Sysplex than many smaller ones. If improved availability is one of your goals, this should not be overlooked - more outages are caused by human error than by hardware failures. Assuming that you have a test sysplex, which we recommend, the test sysplex should be used as learning environment to get familiar with the aspects of managing a sysplex and also as a place to test commands and procedures before they are used on the production system. Cost