Ensuring same systems connectivity

You must ensure same systems connectivity for CF cache structures, lock structure, and storage groups. This is to ensure that jobs running in the Parallel Sysplex® have access to data in both the CFs and storage groups. The lock structure must have global connectivity to all systems in the Parallel Sysplex.

Figure 1 shows how connectivity among systems and storage groups matches connectivity among systems and coupling facilities.

Figure 1. Example of Global Connectivity in a Parallel Sysplex

Connectivity among systems and storage groups must match connectivity among systems and coupling facilities for all systems in the sysplex.

Figure 2 illustrates the problems that can occur if you do not have global connectivity across the Parallel Sysplex:

Figure 2. Example of Insufficient Connectivity in a Parallel Sysplex

In Figure 2, System 3 is connected to both Storage Group 2 and to Coupling Facility 2. This meets the minimum connectivity requirements, but can still cause problems. Because Storage Group 2 data can be placed in Coupling Facility 1, jobs in System 3 can fail if they attempt to access data sets in Storage Group 2 that have been assigned to Coupling Facility 1. You can avoid this by ensuring that, for all systems in the Parallel Sysplex, connectivity among systems and storage groups matches connectivity among systems and coupling facilities.