You should use channel extenders and switches for long-distance connections (up to 500 km and the round trip time is 20 ms or less). Set Fabric to ON and topology to Point-to-Point for the remote replication ports.
Note:
- When the primary and secondary storage systems are connected using switches with a channel extender, and multiple data paths are configured, the capacity of data to be transmitted might concentrate on particular switches, depending on the configuration and the settings of switch routing. Contact customer support for more information.
- Make sure that your channel extenders can support remote I/O. For details, contact customer support.
- Create at least two independent physical paths (one per cluster) between the primary and secondary storage systems for hardware redundancy for this critical element.
- If you plan to use more than 4,000 pairs, when creating pairs you should restrict the number of pairs to 4,000 or less per physical path to distribute the load across multiple physical paths.