Use the CESTPATH command to establish paths between primary site and recovery site logical subsystems or storage controls. A logical subsystem or storage control for a primary volume can have up to eight paths established between it and the logical subsystem or storage control for the pair’s secondary volume. Each CESTPATH command can establish up to eight of these paths.
The logical subsystem or storage control for a specific primary (source) volume may, at any one
time, link to a maximum of 
16
logical subsystems or storage controls for
secondary (target) volumes. You must issue a separate CESTPATH command to establish each path
between different logical subsystems or storage control. Up to eight links can be specified on one
CESTPATH command. See Figure 1 for examples of PPRC path options.
Establish paths before issuing CESTPAIR commands. If you intend to establish paths in both directions between the logical subsystem or storage control and host system (as is needed for P/DAS operations), establish each path before you establish the volume pairs.
The primary volume’s logical subsystem or storage control keeps information about the paths that connect it to the secondary volume’s logical subsystem or storage control. The primary volume’s logical subsystem or storage control automatically attempts to restart a failed path, and then resumes copy operations. If all paths to the secondary volume fail, PPRC suspends the pair. You must re-establish these paths with the CESTPATH command after you have corrected the cause of the failed paths.
- PPRC-capable Licensed Internal Code (LIC) must be installed on both the primary and secondary logical subsystem or storage control.
- For ESS, the appropriate PPRC feature (V1 or V2) must be enabled.
For additional information about hardware requirements, refer to PPRC hardware requirements.