Data paths must be designed to adequately manage all possible amounts of data generated by the host and sent to the P-VOL and S-VOL.
Sufficient bandwidth must be present to handle data transfer of all workload levels. The amount of bandwidth required for your TrueCopy for Mainframe configuration is based on the amount of I/O sent from the host to the primary storage system. You can determine required bandwidth by measuring write workload. Workload data is collected using performance monitoring software. Contact customer support for more information.
Note:
- Create at least two independent data paths (one per cluster) between the primary and secondary systems for hardware redundancy for this critical element.
- When creating more than 4,000 pairs, restrict the number of pairs so that a maximum of 4,000 pairs use one physical path to distribute the loads on the physical paths.
- In a disaster recovery scenario, the same write-workload will be used in the reverse direction. Therefore, when planning TrueCopy for Mainframe for disaster recovery, configure the same number of secondary-to-primary data paths as primary-to-secondary copy paths to maintain normal operations during disaster recovery. Reverse-direction paths must be set up independently of the primary-to-secondary paths.
- When you set up secondary-to-primary data paths, specify the same path group ID as specified for the primary-to-secondary paths.
- You can reverse a primary-to-secondary data path to the secondary-to-primary direction using the PPRC TSO CESTPATH and CDELPATH commands.